000
FXUS63 KGID 242342
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
542 PM CST TUE NOV 24 2009

.AVIATION...00Z KGRI TAF. VFR CONDITIONS WILL CONTINUE THROUGH THE
PERIOD. CLEAR SKIES IN PLACE THIS EVENING WILL GIVE WAY TO
INCREASING MID TO HIGH CLOUDS AFTER MIDNIGHT. CLOUDS SHOULD THEN
THIN OUT AGAIN BUY MID MORNING. THE GREATER IMPACT WILL BE ANOTHER
COLD FRONT SURGING SOUTHEAST WITH INCREASING NORTHWEST
WINDS...ASSOCIATED WITH DECENT PRESSURE RISES BEHIND THE COLD
FRONT. NORTHWEST WINDS WILL BE ESPECIALLY GUSTY BY LATE MORNING
THROUGH MID AFTERNOON WITH GUSTS OF 25 TO 30 KTS.

&&

.PREV DISCUSSION... /ISSUED 316 PM CST TUE NOV 24 2009/

SHORT TERM...TONIGHT THROUGH 12Z THURSDAY. BIGGEST FORECAST
CHALLENGE WILL BE WIND SPEEDS FOR WEDNESDAY.

WATER VAPOR LOOP REVEALS THE TROUGH AXIS OF THE VIGOROUS LONGWAVE
THAT MOVED THROUGH LAST NIGHT CONTINUES ITS WAY INTO THE MISSISSIPPI
VALLEY. THE PROGRESSIVE PATTERN CONTINUES AS A SHORTWAVE TROUGH IS
DIVING SOUTH SOUTHEAST INTO THE NORTHERN HIGH PLAINS TODAY...WITH A
SHORTWAVE RIDGE PRECEDING...AGAIN ALL WITHIN PROGRESSIVE NORTH
NORTHWEST FLOW. A LONGWAVE RIDGE IS MOVING ONTO THE WEST COAST.

FOR TONIGHT....THE AFOREMENTIONED SHORTWAVE RIDGE WILL MOVE
THROUGH...WITH THE RIDGE AXIS CROSSING THE CWA ROUGHLY AROUND
MIDNIGHT. THIS WILL LEAD TO ASSUREDLY DRY CONDITIONS FOR THE
EVENING. THE AFOREMENTIONED SHORTWAVE TROUGH WILL BEGIN MOVING IN
LATE IN THE PERIOD...WITH WEST WIND BECOMING MORE NORTHWEST AND WITH
INCREASING SPEED BEHIND AN ATTENDANT COLD FRONT. SOME FLURRIES ARE
POSSIBLE WITH THE COLD FRONT PASSAGE...BUT MOISTURE IS MEAGER AND I
AM NOT EXPECTING MUCH OUT OF THIS. THE TREND IS A BIT FASTER FOR
THIS PARTICULAR SHORTWAVE...SO I WILL PROBABLY BRING THE ISOLATED
FLURRIES FROM THE PREVIOUS FORECAST SOUTH ANOTHER ROW OF COUNTIES TO
THE STATE LINE FOR THE 06Z TO 12Z TIME PERIOD...A MINOR CHANGE.
CONSIDERING THE PROGRESSIVE NATURE OF THE PATTERN...MODELS ARE IN
REMARKABLE AGREEMENT WITH THE TIMING OF THIS WAVE AND THE CLOSED LOW
ASSOCIATED WITH IT. WENT BELOW MODEL GUIDANCE FOR LOW TEMPERATURE.
THE TEMPERATURE CURVE WILL PROBABLY NOT BE A TYPICAL DIURNAL CURVE
THE PERIOD WILL BEGIN WITH CLEAR OR NEARLY CLEAR SKY...INCREASING
LATER IN THE PERIOD. DEWPOINTS ARE ALSO IN THE LOWER TO MID
20S...WHICH WILL ALSO AID IN THE QUICK DROP OFF. ALSO...WIND SPEEDS
PICK UP AFTER MIDNIGHT AS FRONT MOVES IN. THIS WILL LEND TO A SHARP
DROP OFF IN THE FIRST FEW HOURS OF THE EVENING...AND THEN A STEADY
OR SLOWLY FALLING TEMPERATURE FOR THE REST OF THE NIGHT. WILL GO
GENERALLY BELOW MODEL GUIDANCE VALUES. I KNOCKED DOWN THE DEWPOINTS
A BIT FOR TONIGHT IN THE GRIDS.

FOR WEDNESDAY...A FEW MORNING FLURRIES MAY BE LEFT OVER IN THE
SOUTHERN CWA ASSOCIATED WITH THE COLD FRONT PASSAGE...BUT
AGAIN...NOT MUCH IS EXPECTED WITH THIS. MODELS SUGGEST THAT MIXING
HEIGHTS WILL BE A BIT HIGHER THAN TODAY...NEAR 800 MB BY WEDNESDAY
AFTERNOON...LEADING TO A BIT MORE BRISK CONDITIONS COMPARED TO
CONDITIONS TODAY. MODELS HAVE GENERALLY BACKED OFF A BIT FOR
POTENTIAL WIND GUSTS...BUT WE STILL COULD GET 35 KT WIND GUSTS AND
SUSTAINED WIND SPEEDS LOOK LIKE THEY WILL FLIRT WITH WIND ADVISORY
CRITERION FOR WEDNESDAY AFTERNOON. A CLOSED LOW IS EXPECTED WITH THE
WAVE PASSING THROUGH...BUT ALL MODELS POINT TOWARD THIS FEATURE
REMAINING WELL NORTHEAST OF THE CWA...KEEPING US OUT OF ANY
MEASURABLE PRECIPITATION POTENTIAL. GOING BELOW MODEL GUIDANCE
VALUES FOR HIGH TEMPERATURES...WITH A GOOD LITTLE PUNCH OF COLD AIR
ADVECTION EXPECTED.

FOR WEDNESDAY NIGHT...TROUGH AXIS MOVES EAST OF THE CWA AND HELPS
DEEPEN THE LONGWAVE TROUGH TO THE EAST THAT WAS FIRST DEVELOPED FROM
THE WAVE WHICH PASSED THROUGH LAST NIGHT. THE FIRST WAVE WEAKENS AND
MOVES NORTHEAST INTO CANADA AS THE SECOND WAVE REINFORCES THE
LONGWAVE TROUGH IN THE MISSISSIPPI/OHIO VALLEY. LONGWAVE RIDGING
BEGINS TO BUILD IN ACROSS THE CWA...ONCE AGAIN ASSURING A DRY
FORECAST. HOLDING RELATIVELY CLOSE TO MODEL GUIDANCE NUMBERS FOR LOW
TEMPERATURES. I KNOCKED DOWN DEWPOINTS FOR THIS PERIOD BY A FEW
DEGREES.

LONG TERM...12Z THURSDAY THROUGH TUESDAY.  PRIMARY FORECAST
CONCERN LIES WITH PRECIPITATION CHANCES.

FIRST PORTION OF THE LONG TERM PERIOD...THURSDAY THROUGH
SATURDAY...STILL ON TRACK TO BE DRY.  MODELS IN GOOD AGREEMENT AT
12Z THURSDAY...SHOWING A MORE AMPLIFIED UPPER LEVEL PATTERN ACROSS
THE CONUS.  TROUGH/POTENT LOW PRESSURE SYSTEM WHICH CROSSES THROUGH
ON WEDNESDAY SHIFTS ON INTO THE MIDWEST REGION...WITH A RIDGE
BUILDING IN ACROSS THE ROCKIES AS ANOTHER TROUGH APPROACHES THE
WEST COAST. THIS RIDGE REMAINS THE PRIMARY UPPER LEVEL FEATURE
ACROSS THE REGION THROUGH THE END OF THE WEEK. THE AXIS GRADUALLY
SHIFTS OUT OF THE ROCKIES...EVENTUALLY DRAPED THROUGH THE PLAINS
ON FRIDAY...BEFORE SHIFTING OFF FURTHER EAST AND BEGINNING TO
BREAK DOWN AS THE NEXT SYSTEM APPROACHES. AT THE SFC...HIGH
PRESSURE CENTERED TO THE SOUTH LINGERS AROUND THE CWA DURING THE
FIRST PART OF THURSDAY...BEFORE SHIFTING TO THE EAST AS A TROUGH
OF LOW PRESSURE DEVELOPS ALONG THE FRONT RANGE. THIS WILL BRING
LIGHTER WEST WINDS ON THURSDAY...GRADUALLY SWITCHING TO SOUTH
THURSDAY NIGHT AND CONTINUING ON THROUGH FRIDAY. AS WE GET INTO
SATURDAY...THE UPPER LEVEL PATTERN ACROSS THE PLAINS HAS
TRANSITIONED TO SOUTHWESTERLY FLOW...AS THE NEXT SYSTEM TO IMPACT
THE AREA SITS OVER THE ROCKIES. A PIECE OF MID LEVEL SHORTWAVE
ENERGY MOVING THROUGH WILL PUSH A SFC COLD FRONT INTO THE CWA
DURING THE DAY...BUT NO PRECIPITATION IS EXPECTED. AS FAR AS
TEMPERATURES GO THURS THROUGH SAT...WARMER HIGHS EXPECTED ON
THURSDAY...WITH THE WARMEST READINGS ON FRIDAY AS THAT UPPER LEVEL
RIDGE SITS OVERHEAD. HIGHS EXPECTED TO REACH WELL INTO THE
50S...WITH A FEW LOWER 60S POSSIBLE...ON FRIDAY BEFORE COOLING
BACK DOWN INTO THE UPPER 40S/LOWER 50S FOR SATURDAY.

CONFIDENCE IN THE FORECAST FROM SUNDAY THROUGH TUESDAY IS ON THE LOW
SIDE...AS MODELS CONTINUE TO STRUGGLE WITH THE EVOLUTION OF THE
SYSTEM MOVING OUT OF THE ROCKIES.  TIMING OF THE SYSTEM HAS NOT BEEN
QUITE AS MUCH OF AN ISSUE AS THE LOCATION/STRUCTURE HAS BEEN.
MODELS HAVE NOT VERY CONSISTENT ON WHETHER ITS MORE OF AN OPEN
TROUGH THAT PUSHES THROUGH OR A CLOSED LOW...AND WHETHER THE MORE
ORGANIZED STRUCTURE/LIFT/PRECIP SHIFTS THROUGH THE NORTHERN OR
SOUTHERN PLAINS. FORECAST IS TRENDED MORE TOWARDS THE SLIGHTLY
MORE CONSISTENT ECMWF...AND KEPT PRECIP MENTION CONFINED TO THE
SOUTHERN PORTIONS OF THE CWA...AS THE MAIN UPPER LEVEL SYSTEM
CROSS THROUGH KANSAS. HAVE THE TIMING OF THE POPS RUNNING FROM
SUNDAY THROUGH MONDAY...BUT ADJUSTMENTS OVER THE NEXT FEW DAYS ARE
LIKELY AS MODELS COME INTO BETTER AGREEMENT. REGARDLESS TO THE
EXACT PATH OF THE SYSTEM...COOLER TEMPERATURES ARE EXPECTED WITH
THE PASSAGE OF THE COLD FRONT ON SATURDAY...AND TRENDED BACK HIGHS
FOR SUN THROUGH TUES BACK INTO THE UPPER 30S/LOWER 40S.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KGID 242116
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
316 PM CST TUE NOV 24 2009

.SHORT TERM...TONIGHT THROUGH 12Z THURSDAY. BIGGEST FORECAST
CHALLENGE WILL BE WIND SPEEDS FOR WEDNESDAY.

WATER VAPOR LOOP REVEALS THE TROUGH AXIS OF THE VIGOROUS LONGWAVE
THAT MOVED THROUGH LAST NIGHT CONTINUES ITS WAY INTO THE MISSISSIPPI
VALLEY. THE PROGRESSIVE PATTERN CONTINUES AS A SHORTWAVE TROUGH IS
DIVING SOUTH SOUTHEAST INTO THE NORTHERN HIGH PLAINS TODAY...WITH A
SHORTWAVE RIDGE PRECEDING...AGAIN ALL WITHIN PROGRESSIVE NORTH
NORTHWEST FLOW. A LONGWAVE RIDGE IS MOVING ONTO THE WEST COAST.

FOR TONIGHT....THE AFOREMENTIONED SHORTWAVE RIDGE WILL MOVE
THROUGH...WITH THE RIDGE AXIS CROSSING THE CWA ROUGHLY AROUND
MIDNIGHT. THIS WILL LEAD TO ASSUREDLY DRY CONDITIONS FOR THE
EVENING. THE AFOREMENTIONED SHORTWAVE TROUGH WILL BEGIN MOVING IN
LATE IN THE PERIOD...WITH WEST WIND BECOMING MORE NORTHWEST AND WITH
INCREASING SPEED BEHIND AN ATTENDANT COLD FRONT. SOME FLURRIES ARE
POSSIBLE WITH THE COLD FRONT PASSAGE...BUT MOISTURE IS MEAGER AND I
AM NOT EXPECTING MUCH OUT OF THIS. THE TREND IS A BIT FASTER FOR
THIS PARTICULAR SHORTWAVE...SO I WILL PROBABLY BRING THE ISOLATED
FLURRIES FROM THE PREVIOUS FORECAST SOUTH ANOTHER ROW OF COUNTIES TO
THE STATE LINE FOR THE 06Z TO 12Z TIME PERIOD...A MINOR CHANGE.
CONSIDERING THE PROGRESSIVE NATURE OF THE PATTERN...MODELS ARE IN
REMARKABLE AGREEMENT WITH THE TIMING OF THIS WAVE AND THE CLOSED LOW
ASSOCIATED WITH IT. WENT BELOW MODEL GUIDANCE FOR LOW TEMPERATURE.
THE TEMPERATURE CURVE WILL PROBABLY NOT BE A TYPICAL DIURNAL CURVE
THE PERIOD WILL BEGIN WITH CLEAR OR NEARLY CLEAR SKY...INCREASING
LATER IN THE PERIOD. DEWPOINTS ARE ALSO IN THE LOWER TO MID
20S...WHICH WILL ALSO AID IN THE QUICK DROP OFF. ALSO...WIND SPEEDS
PICK UP AFTER MIDNIGHT AS FRONT MOVES IN. THIS WILL LEND TO A SHARP
DROP OFF IN THE FIRST FEW HOURS OF THE EVENING...AND THEN A STEADY
OR SLOWLY FALLING TEMPERATURE FOR THE REST OF THE NIGHT. WILL GO
GENERALLY BELOW MODEL GUIDANCE VALUES. I KNOCKED DOWN THE DEWPOINTS
A BIT FOR TONIGHT IN THE GRIDS.

FOR WEDNESDAY...A FEW MORNING FLURRIES MAY BE LEFT OVER IN THE
SOUTHERN CWA ASSOCIATED WITH THE COLD FRONT PASSAGE...BUT
AGAIN...NOT MUCH IS EXPECTED WITH THIS. MODELS SUGGEST THAT MIXING
HEIGHTS WILL BE A BIT HIGHER THAN TODAY...NEAR 800 MB BY WEDNESDAY
AFTERNOON...LEADING TO A BIT MORE BRISK CONDITIONS COMPARED TO
CONDITIONS TODAY. MODELS HAVE GENERALLY BACKED OFF A BIT FOR
POTENTIAL WIND GUSTS...BUT WE STILL COULD GET 35 KT WIND GUSTS AND
SUSTAINED WIND SPEEDS LOOK LIKE THEY WILL FLIRT WITH WIND ADVISORY
CRITERION FOR WEDNESDAY AFTERNOON. A CLOSED LOW IS EXPECTED WITH THE
WAVE PASSING THROUGH...BUT ALL MODELS POINT TOWARD THIS FEATURE
REMAINING WELL NORTHEAST OF THE CWA...KEEPING US OUT OF ANY
MEASURABLE PRECIPITATION POTENTIAL. GOING BELOW MODEL GUIDANCE
VALUES FOR HIGH TEMPERATURES...WITH A GOOD LITTLE PUNCH OF COLD AIR
ADVECTION EXPECTED.

FOR WEDNESDAY NIGHT...TROUGH AXIS MOVES EAST OF THE CWA AND HELPS
DEEPEN THE LONGWAVE TROUGH TO THE EAST THAT WAS FIRST DEVELOPED FROM
THE WAVE WHICH PASSED THROUGH LAST NIGHT. THE FIRST WAVE WEAKENS AND
MOVES NORTHEAST INTO CANADA AS THE SECOND WAVE REINFORCES THE
LONGWAVE TROUGH IN THE MISSISSIPPI/OHIO VALLEY. LONGWAVE RIDGING
BEGINS TO BUILD IN ACROSS THE CWA...ONCE AGAIN ASSURING A DRY
FORECAST. HOLDING RELATIVELY CLOSE TO MODEL GUIDANCE NUMBERS FOR LOW
TEMPERATURES. I KNOCKED DOWN DEWPOINTS FOR THIS PERIOD BY A FEW
DEGREES.

.LONG TERM...12Z THURSDAY THROUGH TUESDAY.  PRIMARY FORECAST
CONCERN LIES WITH PRECIPITATION CHANCES.

FIRST PORTION OF THE LONG TERM PERIOD...THURSDAY THROUGH
SATURDAY...STILL ON TRACK TO BE DRY.  MODELS IN GOOD AGREEMENT AT
12Z THURSDAY...SHOWING A MORE AMPLIFIED UPPER LEVEL PATTERN ACROSS
THE CONUS.  TROUGH/POTENT LOW PRESSURE SYSTEM WHICH CROSSES THROUGH
ON WEDNESDAY SHIFTS ON INTO THE MIDWEST REGION...WITH A RIDGE
BUILDING IN ACROSS THE ROCKIES AS ANOTHER TROUGH APPROACHES THE
WEST COAST. THIS RIDGE REMAINS THE PRIMARY UPPER LEVEL FEATURE
ACROSS THE REGION THROUGH THE END OF THE WEEK. THE AXIS GRADUALLY
SHIFTS OUT OF THE ROCKIES...EVENTUALLY DRAPED THROUGH THE PLAINS
ON FRIDAY...BEFORE SHIFTING OFF FURTHER EAST AND BEGINNING TO
BREAK DOWN AS THE NEXT SYSTEM APPROACHES. AT THE SFC...HIGH
PRESSURE CENTERED TO THE SOUTH LINGERS AROUND THE CWA DURING THE
FIRST PART OF THURSDAY...BEFORE SHIFTING TO THE EAST AS A TROUGH
OF LOW PRESSURE DEVELOPS ALONG THE FRONT RANGE. THIS WILL BRING
LIGHTER WEST WINDS ON THURSDAY...GRADUALLY SWITCHING TO SOUTH
THURSDAY NIGHT AND CONTINUING ON THROUGH FRIDAY. AS WE GET INTO
SATURDAY...THE UPPER LEVEL PATTERN ACROSS THE PLAINS HAS
TRANSITIONED TO SOUTHWESTERLY FLOW...AS THE NEXT SYSTEM TO IMPACT
THE AREA SITS OVER THE ROCKIES. A PIECE OF MID LEVEL SHORTWAVE
ENERGY MOVING THROUGH WILL PUSH A SFC COLD FRONT INTO THE CWA
DURING THE DAY...BUT NO PRECIPITATION IS EXPECTED. AS FAR AS
TEMPERATURES GO THURS THROUGH SAT...WARMER HIGHS EXPECTED ON
THURSDAY...WITH THE WARMEST READINGS ON FRIDAY AS THAT UPPER LEVEL
RIDGE SITS OVERHEAD. HIGHS EXPECTED TO REACH WELL INTO THE
50S...WITH A FEW LOWER 60S POSSIBLE...ON FRIDAY BEFORE COOLING
BACK DOWN INTO THE UPPER 40S/LOWER 50S FOR SATURDAY.

CONFIDENCE IN THE FORECAST FROM SUNDAY THROUGH TUESDAY IS ON THE LOW
SIDE...AS MODELS CONTINUE TO STRUGGLE WITH THE EVOLUTION OF THE
SYSTEM MOVING OUT OF THE ROCKIES.  TIMING OF THE SYSTEM HAS NOT BEEN
QUITE AS MUCH OF AN ISSUE AS THE LOCATION/STRUCTURE HAS BEEN.
MODELS HAVE NOT VERY CONSISTENT ON WHETHER ITS MORE OF AN OPEN
TROUGH THAT PUSHES THROUGH OR A CLOSED LOW...AND WHETHER THE MORE
ORGANIZED STRUCTURE/LIFT/PRECIP SHIFTS THROUGH THE NORTHERN OR
SOUTHERN PLAINS. FORECAST IS TRENDED MORE TOWARDS THE SLIGHTLY
MORE CONSISTENT ECMWF...AND KEPT PRECIP MENTION CONFINED TO THE
SOUTHERN PORTIONS OF THE CWA...AS THE MAIN UPPER LEVEL SYSTEM
CROSS THROUGH KANSAS. HAVE THE TIMING OF THE POPS RUNNING FROM
SUNDAY THROUGH MONDAY...BUT ADJUSTMENTS OVER THE NEXT FEW DAYS ARE
LIKELY AS MODELS COME INTO BETTER AGREEMENT. REGARDLESS TO THE
EXACT PATH OF THE SYSTEM...COOLER TEMPERATURES ARE EXPECTED WITH
THE PASSAGE OF THE COLD FRONT ON SATURDAY...AND TRENDED BACK HIGHS
FOR SUN THROUGH TUES BACK INTO THE UPPER 30S/LOWER 40S.

&&

.AVIATION...18Z KGRI TAF. VFR CONDITIONS FORECAST THROUGH THE
PERIOD. ESSENTIALLY CLEAR SKIES IN PLACE FOR THE FIRST 15 HOURS OR
SO...IN THE WAKE OF A DEPARTING LOW PRESSURE SYSTEM OVER IOWA. THE
ONLY CONCERN THIS AFTERNOON IS NORTHWEST WINDS GUSTING TO OVER 25
KTS AT TIMES...BEFORE SUBSIDING CONSIDERABLY BY SUNSET.
OVERNIGHT...A FAST MOVING MID LEVEL DISTURBANCE WILL APPROACH FROM
THE DAKOTAS...SPREADING A DECK OF VFR CLOUDS ACROSS THE
AREA...ALONG WITH THE POSSIBILITY OF SOME SNOW FLURRIES. HELD OFF
ON ANY MENTION OF SNOW...AS COVERAGE AND IMPACT SHOULD BE QUITE
MINIMAL. OF GREATER IMPACT WILL BE ANOTHER SURGE OF NORTHWEST
WINDS...ASSOCIATED WITH DECENT PRESSURE RISES BEHIND A PASSING
COLD FRONT. ATTEMPTED TO PROVIDE SOME TIMING DETAIL TO THE
INCREASING WINDS DURING THE LATTER PART OF THE PERIOD...AS GUSTS
OF 25 TO 30 KTS SHOULD BE COMMON BY MID TO LATE MORNING.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KOAX 242031
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
230 PM CST TUE NOV 24 2009

.SHORT TERM...TONIGHT THROUGH FRIDAY.
...MAIN PROBLEM IS LOW POPS WEDNESDAY WITH NEXT WAVE AND
TEMPERATURES...UPPER AIR ANALYSIS THIS MORNING SHOWED A DYNAMIC AND
PROGRESSIVE PATTERN OVER NORTH AMERICA AS INDICATED BY THE HEIGHT
RISE/FALL CENTERS.  AT 300 MB...160 METER HEIGHT FALL WAS NOTED OVER
TOPEKA ASSOCIATED WITH THE UPPER LOW SPINNING OVER IOWA
TODAY...BALANCED BY A 160 METER HEIGHT RISE IN BOULDER AT 12Z.
HOWEVER... A 200 METER FALL WAS NOTED IN CENTRAL ALBERTA ASSOCIATED
WITH THE NEXT UPSTREAM SHORTWAVE.  THIS SYSTEM WILL BE THE FOCUS FOR
THIS FORECAST PERIOD.

WATERVAPOR LOOP INDICATES THIS SHORTWAVE IS MOVING SOUTHEAST AT 35
KNOTS BASED ON MOTION OF VORT MAX AND HEIGHT FALL CENTER...HOWEVER
EXPECT IT TO ACCELERATE AS IT MOVES A BIT MORE SOUTHEAST.  WEAK
UPPER RIDGE OVER THE WEST COAST IS PROGGED TO STRENGTHEN...THUS
RESULTING IN A MORE MERIDIONAL FLOW OVER CENTRAL NORTH AMERICA AND
PULLING THE SHORTWAVE INTO THE FASTER NORTHWEST FLOW.

AT 850 MB...-10C WAS OBSERVED IN NORTHERN ALBERTA THIS MORNING.  THE
GFS IS FAIRLY QUICK TO BRING THIS AIR SOUTH BEHIND THE WAVE...BUT
THERE IS LITTLE OR NO SNOW COVER OVER THE NORTHERN PLAINS.  THUS
EXPECT THE AIRMASS TO MODIFY SOME...WITH A SOLUTION CLOSER TO THE
NAM AND ECMWF FOR 850 TEMPERATURES.  GOING TEMPERATURES THROUGH
THURSDAY ARE SOMEWHAT CONSISTENT WITH THESE 850 TEMPERATURES...THUS
MADE ONLY MINOR CHANGES.  HIGHS ON FRIDAY LOOK TO BE WARMER DUE TO A
QUICK SHOT OF WARM AIR ADVECTION AND LITTLE CLOUD COVER...SO BUMPED
HIGHS ON FRIDAY SEVERAL DEGREES INTO THE MID 50S.

THE SHORTWAVE WILL GENERATE A BROAD AREA OF VERTICAL MOTION THROUGH
DPVA AND FRONTOGENESIS WITH THE BAROCLINICITY MUCH OF THE DAY ON
WEDNESDAY...HOWEVER BOTH MODELS AGREE ON A 110+ KNOT 300 MB JET MAX
MOVING THROUGH THE DAKOTAS AROUND 00Z.  ON THE NOSE OF THIS JET
SHOULD BE A DEFINED AREA OF ENHANCED VERTICAL MOTION FROM
DIVERGENCE...FOCUSED MORE OVER OUR NORTHERN COUNTIES AROUND THAT
TIME.  THAT APPEARS TO BE OUR ONLY CHANCE OF GETTING ANY MEASURABLE
PRECIPITATION WITH THIS SYSTEM...AND THAT WOULD STILL BE QUITE
LIGHT.  TEMPERATURE PROFILE WOULD SUGGEST SNOW...BUT NEAR SURFACE
TEMPERATURES SHOULD BE WARM ENOUGH TO SEE RAIN MIXED IN TOO.
BIGGEST PROBLEM WITH PRECIPITATION GENERATION WILL BE A RATHER DRY
AIRMASS...WHICH WILL SEE MOISTURE ADDED FROM THE MID LEVELS...BUT
LIKELY NOT ENOUGH TO SATURATE LOWER LEVELS.

FINALLY...REGARDING THE LIGHT RAIN THIS EVENING...WILL INCLUDE A
COUPLE OF HOURS OF DRIZZLE MAINLY FROM THE MISSOURI RIVER EAST WHILE
UPPER LOW MOVES SLOWLY EAST.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY.

THE PERIOD BEGINS DRY AS AN UPPER RIDGE AXIS MOVES OVER THE CNTRL
CONUS. INCREASING SRLY LOW LEVEL FLOW AHEAD OF AN APPROACHING COLD
FRONT SHOULD BRING IN FAIRLY MILD TEMPS FOR SATURDAY. CONFIDENCE IS
ABOVE AVERAGE THAT A POSITIVELY TILTED LONG WAVE UPPER TROF WL MOVE
ACROSS THE NATIONS MID SECTION LATE IN THE WEEKEND/EARLY NEXT WEEK.
HAVE FOLLOWED MORE CLOSELY TO A 00/12Z ECMWF SOLUTION WHICH HPC HAS
TRENDED TOWARD AS WELL AS OUR NEIGHBORING OFFICES. THIS SOLUTION
SPLITS THE TROF INTO A NRN AND SRN STREAM AND EVENTUALLY MERGES THEM
INTO ONE BIG CYCLONE OVER THE SRN PLAINS EARLY NEXT WEEK. NRN STREAM
ENERGY SHOULD DIG COLDER TEMPS DOWN ACROSS THE AREA TO EVENTUALLY
WORK INTO THE MERGED UPPER LOW. IF CURRENT MODEL TIMING AND TRACK
HOLDS...THE SOUTHERN HALF OF THE CWA COULD SEE SOME SIGNIFICANT
PCPN. TOO MANY UNCERTAINTIES OUT IN DAYS 6/7 TO PUT HIGH CONFIDENCE
INTO HIGH POPS AT THIS POINT.

&&

.AVIATION...
TAF SITES KOFK/KOMA/KLNK

18Z TAFS

OCCASIONAL IFR CIGS AND MVFR VISIBILITIES WILL CONTINUE THROUGH 00Z
AT KOMA AS LOW CLOUDS/SHOWERS ROTATE AROUND LOW PRESSURE SYSTEM
DRIFTING EAST THROUGH IOWA. AN IMPROVEMENT TO VFR CONDITIONS IS
EXPECTED NEAR OR SHORTLY AFTER 00Z. NORTHWEST WINDS 15 TO 25 KT
SHOULD CONTINUE THROUGH 00Z AT ALL EASTERN NEBRASKA TAF SITES BEFORE
DROPPING TO 12KT. ANOTHER COLD FRONT RACING SOUTHEAST FROM THE
NORTHERN PLAINS WILL ARRIVE AT KOFK AROUND 09Z AND KOMA/KLNK AREAS
BY 12Z. CIGS SHOULD REMAIN VFR ALONG AND BEHIND FRONTAL
BOUNDARY...BUT NORTHWEST WINDS WILL INCREASE INTO THE 20 TO 30KT
RANGE BETWEEN 12Z AND 18Z WEDNESDAY.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

$$

NIETFELD/KERN/DERGAN

000
FXUS63 KLBF 242025
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
225 PM CST TUE NOV 24 2009

.SYNOPSIS...
    AT 19Z...HAND ANALYSIS OF MSL DATA SHOWED THE STRONG CYCLONE
CENTERED ALONG THE IOWA-MISSOURI LINE NORTHWEST OF ST. LOUIS.
ANOTHER CLOSED LOW WAS LOCATED IN EASTERN MANITOBA NORTHEAST OF LAKE
WINNIPEG WITH A WEAK FRONT THROUGH NORTHWEST MINNESOTA AND ACROSS
THE DAKOTAS TO NEAR THE BLACK HILLS. VISIBLE SATELLITE IMAGERY
SHOWED A BAND OF CUMULUS CLOUDS FORMING ALONG THE DAKOTA SURFACE
FRONT. IN THE UPPER LEVELS...THERE WAS A BROAD BAROCLINIC ZONE
INDICATED IN THE 6.7 MICRON IMAGERY ACROSS MONTANA AND NORTHERN
WYOMING.
&&

.SHORT/MEDIUM RANGE...TONIGHT THROUGH SATURDAY.
    WITH THE SURFACE FRONT PLUNGING SOUTHWARD RAPIDLY...THE SYSTEM
RELATIVE ISENTROPIC LIFT SHOULD BE ENOUGH TO GENERATE ISOLATED LIGHT
SNOW SHOWERS TONIGHT IN THE NORTHEAST NEBRASKA PANHANDLE...
ESPECIALLY AFTER MIDNIGHT. THERE SHOULD ALSO BE SOME FRONTOGENESIS
AS THE UPPER LEVEL BAROCLINIC SYSTEM REINFORCES THE FRONT. BECAUSE
OF ITS FAST MOVEMENT AND A LACK OF AVAILABLE MOISTURE...LITTLE OR NO
ACCUMULATION IS EXPECTED.
    THEN...AS A RIDGE BUILDS OVER THE ROCKY MOUNTAIN REGION...MILD
TEMPERATURES ARE LIKELY FRIDAY. THEN...ANOTHER FRONT WILL BRING
COLDER TEMPERATURES ONCE AGAIN. ALSO...THE SYSTEM SATURDAY WILL
PROBABLY BE STRONG ENOUGH FOR AT LEAST A SLIGHT CHANCE OF LIGHT
SNOW.

.LONG RANGE...SATURDAY NIGHT THROUGH TUESDAY.
    AFTER SATURDAY...THERE IS AN INCREASING RANGE OF SOLUTIONS AMONG
THE MEDIUM AND LONG RANGE SIMULATIONS IN THEIR HANDLING OF THE UPPER
TROUGH CROSSING THE PLAINS EARLY NEXT WEEK. THE 12Z OPERATIONAL GFS
SHOWS PRETTY DECENT CONSISTENCY WITH THE 00Z GFS AND IS
SIGNIFICANTLY FASTER THAN THE ECMWF AND DGEX WITH THAT UPPER TROUGH.
THE FASTER SOLUTION SEEMS TO HAVE THE SUPPORT OF THE GEM AND THE GFS
ENSEMBLE MEAN AND THUS THE NAEFS. WE WILL LEAN TOWARD THE FASTER
GFS...BUT OUR CONFIDENCE IS NOT REAL HIGH FOR THE SUNDAY THROUGH
TUESDAY PERIOD. THIS WOULD USHER IN A PRETTY COLD PERIOD BY MONDAY
OR TUESDAY AS UPPER FLOW FROM THE YUKON VALLEY BRINGS SOME ARCTIC
AIR TO THE NORTHERN HIGH PLAINS. THE NAEFS SHOWS THE COLDER AIR
ARRIVING WEDNESDAY OR LATER.
&&

.AVIATION...
    GUSTY NW WINDS CONTINUE THIS EVENING...UNTIL SUNSET. THEN WINDS
DIMINISH AS THE BOUNDARY LAYER DECOUPLES. A WEAK FRONT WILL SLIDE
SOUTH ACROSS THE REGION OVERNIGHT...BRINGING A CHANCE FOR SOME LIGHT
SNOW AND MVFR CIGS. BEHIND THE FRONT WINDS ALOFT INCREASE...HOWEVER
COLD AIR ADVECTION SHOULD MIX DOWN ENOUGH WIND DESPITE THE DECOUPLED
BOUNDARY LAYER TO KEEP THE MENTION OF LLWS BELOW INCLUSION CRITERIA
IN THE TAF. WILL CONTINUE TO MONITOR. THEN TOMORROW SYSTEM EXITS
WITH A RETURN TO CLR SKIES AND WINDS AROUND 10 TO 15 KTS. &&

.LBF
WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$
SHORT/MEDIUM RANGE...SPRINGER
AVIATION...MASEK

000
FXUS63 KGID 241752
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1152 AM CST TUE NOV 24 2009

.AVIATION...18Z KGRI TAF. VFR CONDITIONS FORECAST THROUGH THE
PERIOD. ESSENTIALLY CLEAR SKIES IN PLACE FOR THE FIRST 15 HOURS OR
SO...IN THE WAKE OF A DEPARTING LOW PRESSURE SYSTEM OVER IOWA. THE
ONLY CONCERN THIS AFTERNOON IS NORTHWEST WINDS GUSTING TO OVER 25
KTS AT TIMES...BEFORE SUBSIDING CONSIDERABLY BY SUNSET.
OVERNIGHT...A FAST MOVING MID LEVEL DISTURBANCE WILL APPROACH FROM
THE DAKOTAS...SPREADING A DECK OF VFR CLOUDS ACROSS THE
AREA...ALONG WITH THE POSSIBILITY OF SOME SNOW FLURRIES. HELD OFF
ON ANY MENTION OF SNOW...AS COVERAGE AND IMPACT SHOULD BE QUITE
MINIMAL. OF GREATER IMPACT WILL BE ANOTHER SURGE OF NORTHWEST
WINDS...ASSOCIATED WITH DECENT PRESSURE RISES BEHIND A PASSING
COLD FRONT. ATTEMPTED TO PROVIDE SOME TIMING DETAIL TO THE
INCREASING WINDS DURING THE LATTER PART OF THE PERIOD...AS GUSTS
OF 25 TO 30 KTS SHOULD BE COMMON BY MID TO LATE MORNING.

&&

.PREV DISCUSSION... /ISSUED 338 AM CST TUE NOV 24 2009/

DISCUSSION...EARLY MORNING WATER VAPOR IMAGERY SHOWED THE UPPER LOW
SPINNING OVER NORTHEAST KS. NEAR SURFACE TEMPERATURES WHERE THE
PRECIPITATION IS FALLING HAVE REMAINED WARM ENOUGH THROUGH THE NIGHT
TO KEEP THE PRECIP IN OUR CWA IN THE FORM OF RAIN. RADAR SHOWS THE
PRECIP ACROSS THE CWA CONTINUING TO WIND DOWN FAIRLY QUICKLY AS
DEFORMATION BAND EXTENDING FROM CENTRAL KS THROUGH NORTHEAST NE
FADES AT THE EXPENSE OF MAIN DEFORMATION BAND ARCING FROM
NORTHEAST KS INTO SOUTHWEST IA. JUST SOME LIGHT SHOWERS LEFT EAST
OF HWY 14 AS OF 09Z AND THESE WILL CONTINUE TO FADE EARLY THIS
MORNING. SURFACE ANALYSIS SHOWED LOW NEAR THE NORTHEAST
KS/NORTHWEST MO BORDER WITH NORTHWEST WINDS IN PLACE ACROSS THE
CWA ON THE BACKSIDE OF THE LOW.

THE UPPER LOW WILL LIFT INTO IA/MO TODAY...WITH SUBSIDENCE
SPREADING ACROSS THE FORECAST AREA IN WAKE OF THIS
SYSTEM....BRINGING CLEARING SKIES FROM WEST TO EAST. FORECAST
SOUNDINGS INDICATE MIXING TO AROUND 825MB TODAY...WHICH COMBINED
WITH THE DOWNSLOPE COMPONENT TO NORTHWEST WINDS...WILL SUPPORT
HIGHS IN THE UPPER 40S TO LOWER 50S. SPEAKING OF THE WINDS...THEY
WILL BE A LITTLE BLUSTERY TODAY IN THE TIGHTENED PRESSURE GRADIENT
BETWEEN THE EXITING LOW AND SURFACE HIGH OVER THE ROCKIES. THE
WINDS WILL BEGIN TO WEAKEN BY LATE AFTERNOON HOWEVER AS THE
GRADIENT RELAXES IN RESPONSE TO THE SURFACE LOW PULLING INTO
EASTERN IA/MO.

ANOTHER UPPER TROUGH WILL DIVE SOUTHEAST THROUGH THE NORTHERN PLAINS
TONIGHT...INTO THE MID MS VALLEY ON WEDNESDAY. THIS SYSTEM WILL PUSH
A COLD FRONT THROUGH THE CWA LATE TONIGHT INTO WEDNESDAY
MORNING...KNOCKING HIGHS ON WEDNESDAY BACK INTO THE LOWER 40S NORTH
TO AROUND 50F SOUTH. MOISTURE WILL BE LACKING FOR THIS SYSTEM TO
WORK WITH...HOWEVER LFQ OF 110KT UPPER JET NOSING IN...MODEST H5-H3
Q-VECTOR CONVERGENCE...AND AT LEAST SOME WEAK MID-LEVEL
FRONTOGENESIS ALL POINT TO PRETTY DECENT FORCING WITH THIS
SYSTEM...WHICH MAY BE SUFFICIENT TO SQUEEZE OUT SOME FLURRIES LATE
TONIGHT INTO WEDNESDAY MORNING DESPITE THE LACK OF AVAILABLE
MOISTURE. HENCE INSERTED ISOLATED FLURRIES IN THE NORTH AFTER
MIDNIGHT TONIGHT...WORKING SOUTH WEDNESDAY MORNING. IT WILL BE
BRISK AGAIN ON WEDNESDAY AS NORTHWEST WINDS BLOW BEHIND THE FRONT.

A NORTHWEST FLOW ALOFT TAKES HOLD OF THE AREA WEDNESDAY NIGHT INTO
THANKSGIVING DAY IN BETWEEN THIS LOW WHICH PUSHES EAST...AND AN
UPPER RIDGE THAT SHIFTS EASTWARD OVER THE ROCKIES ON THANKSGIVING.
THIS SUBSIDENT PATTERN WILL BRING DRY CONDITIONS...MOSTLY SUNNY
SKIES...AND ABOVE AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 40S
TO LOWER 50S ON THANKSGIVING. THE UPPER RIDGE SHIFTS EAST OVER THE
PLAINS ON FRIDAY...BRINGING MILD TEMPS AND CONTINUED DRY WEATHER.
THE NEXT UPPER TROUGH DIGS OVER THE WESTERN CONUS ON SATURDAY. STILL
A LOT OF MODEL DIFFERENCES REGARDING THIS SYSTEM AS IT ADVANCES
EASTWARD...AND MADE NO CHANGES TO THESE OUTER PERIODS...BUT IT WILL
BE A SYSTEM TO KEEP AN EYE ON AS WE HEAD LATER INTO THE WEEKEND
ESPECIALLY INTO EARLY NEXT WEEK.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

AVIATION...PFANNKUCH
PREV DISCUSSION...KB

000
FXUS63 KGID 241124
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
524 AM CST TUE NOV 24 2009

.AVIATION...12Z TAF. VFR CONDITIONS ARE EXPECTED TO PREVAIL AT KGRI
FOR MUCH OF THE PERIOD. MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO
SPIN AROUND A DEPARTING STORM SYSTEM...BUT EVEN THOSE SHOULD
BECOME FEWER THIS MORNING. WINDS WILL INCREASE THIS MORNING AND
SHOULD BECOME GUSTY. SEVERAL LOCATIONS ACROSS SOUTH CENTRAL
NEBRASKA ARE ALREADY REPORTING GUSTY NORTHWEST WINDS...AND WILL
CARRY WIND GUSTS AT KGRI FROM THE START. WINDS SHOULD DIMINISH
LATE THIS AFTERNOON. A FAST MOVING STORM SYSTEM WILL BEGIN TO
APPROACH THE REGION LATE TONIGHT...AND EXPECT MID AND HIGH LEVEL
CLOUDS WILL AGAIN INCREASE AS THIS APPROACHES. WILL BRING A
CEILING AROUND 7KFT BACK TO KGRI LATE TONIGHT...WITH SOME LOWERING
OF THE CEILING STILL POSSIBLE TOWARDS THE END OF THE TAF PERIOD. A
FEW SNOW FLURRIES MAY ACCOMPANY THE INCREASING CLOUDS...BUT THEY
APPEAR MINOR ENOUGH TO NOT INCLUDE YET.

&&

.PREV DISCUSSION... /ISSUED 338 AM CST TUE NOV 24 2009/

DISCUSSION...EARLY MORNING WATER VAPOR IMAGERY SHOWED THE UPPER LOW
SPINNING OVER NORTHEAST KS. NEAR SURFACE TEMPERATURES WHERE THE
PRECIPITATION IS FALLING HAVE REMAINED WARM ENOUGH THROUGH THE NIGHT
TO KEEP THE PRECIP IN OUR CWA IN THE FORM OF RAIN. RADAR SHOWS THE
PRECIP ACROSS THE CWA CONTINUING TO WIND DOWN FAIRLY QUICKLY AS
DEFORMATION BAND EXTENDING FROM CENTRAL KS THROUGH NORTHEAST NE
FADES AT THE EXPENSE OF MAIN DEFORMATION BAND ARCING FROM
NORTHEAST KS INTO SOUTHWEST IA. JUST SOME LIGHT SHOWERS LEFT EAST
OF HWY 14 AS OF 09Z AND THESE WILL CONTINUE TO FADE EARLY THIS
MORNING. SURFACE ANALYSIS SHOWED LOW NEAR THE NORTHEAST
KS/NORTHWEST MO BORDER WITH NORTHWEST WINDS IN PLACE ACROSS THE
CWA ON THE BACKSIDE OF THE LOW.

THE UPPER LOW WILL LIFT INTO IA/MO TODAY...WITH SUBSIDENCE
SPREADING ACROSS THE FORECAST AREA IN WAKE OF THIS
SYSTEM....BRINGING CLEARING SKIES FROM WEST TO EAST. FORECAST
SOUNDINGS INDICATE MIXING TO AROUND 825MB TODAY...WHICH COMBINED
WITH THE DOWNSLOPE COMPONENT TO NORTHWEST WINDS...WILL SUPPORT
HIGHS IN THE UPPER 40S TO LOWER 50S. SPEAKING OF THE WINDS...THEY
WILL BE A LITTLE BLUSTERY TODAY IN THE TIGHTENED PRESSURE GRADIENT
BETWEEN THE EXITING LOW AND SURFACE HIGH OVER THE ROCKIES. THE
WINDS WILL BEGIN TO WEAKEN BY LATE AFTERNOON HOWEVER AS THE
GRADIENT RELAXES IN RESPONSE TO THE SURFACE LOW PULLING INTO
EASTERN IA/MO.

ANOTHER UPPER TROUGH WILL DIVE SOUTHEAST THROUGH THE NORTHERN PLAINS
TONIGHT...INTO THE MID MS VALLEY ON WEDNESDAY. THIS SYSTEM WILL PUSH
A COLD FRONT THROUGH THE CWA LATE TONIGHT INTO WEDNESDAY
MORNING...KNOCKING HIGHS ON WEDNESDAY BACK INTO THE LOWER 40S NORTH
TO AROUND 50F SOUTH. MOISTURE WILL BE LACKING FOR THIS SYSTEM TO
WORK WITH...HOWEVER LFQ OF 110KT UPPER JET NOSING IN...MODEST H5-H3
Q-VECTOR CONVERGENCE...AND AT LEAST SOME WEAK MID-LEVEL
FRONTOGENESIS ALL POINT TO PRETTY DECENT FORCING WITH THIS
SYSTEM...WHICH MAY BE SUFFICIENT TO SQUEEZE OUT SOME FLURRIES LATE
TONIGHT INTO WEDNESDAY MORNING DESPITE THE LACK OF AVAILABLE
MOISTURE. HENCE INSERTED ISOLATED FLURRIES IN THE NORTH AFTER
MIDNIGHT TONIGHT...WORKING SOUTH WEDNESDAY MORNING. IT WILL BE
BRISK AGAIN ON WEDNESDAY AS NORTHWEST WINDS BLOW BEHIND THE FRONT.

A NORTHWEST FLOW ALOFT TAKES HOLD OF THE AREA WEDNESDAY NIGHT INTO
THANKSGIVING DAY IN BETWEEN THIS LOW WHICH PUSHES EAST...AND AN
UPPER RIDGE THAT SHIFTS EASTWARD OVER THE ROCKIES ON THANKSGIVING.
THIS SUBSIDENT PATTERN WILL BRING DRY CONDITIONS...MOSTLY SUNNY
SKIES...AND ABOVE AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 40S
TO LOWER 50S ON THANKSGIVING. THE UPPER RIDGE SHIFTS EAST OVER THE
PLAINS ON FRIDAY...BRINGING MILD TEMPS AND CONTINUED DRY WEATHER.
THE NEXT UPPER TROUGH DIGS OVER THE WESTERN CONUS ON SATURDAY. STILL
A LOT OF MODEL DIFFERENCES REGARDING THIS SYSTEM AS IT ADVANCES
EASTWARD...AND MADE NO CHANGES TO THESE OUTER PERIODS...BUT IT WILL
BE A SYSTEM TO KEEP AN EYE ON AS WE HEAD LATER INTO THE WEEKEND
ESPECIALLY INTO EARLY NEXT WEEK.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KGID 240939
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
338 AM CST TUE NOV 24 2009

.DISCUSSION...EARLY MORNING WATER VAPOR IMAGERY SHOWED THE UPPER LOW
SPINNING OVER NORTHEAST KS. NEAR SURFACE TEMPERATURES WHERE THE
PRECIPITATION IS FALLING HAVE REMAINED WARM ENOUGH THROUGH THE NIGHT
TO KEEP THE PRECIP IN OUR CWA IN THE FORM OF RAIN. RADAR SHOWS THE
PRECIP ACROSS THE CWA CONTINUING TO WIND DOWN FAIRLY QUICKLY AS
DEFORMATION BAND EXTENDING FROM CENTRAL KS THROUGH NORTHEAST NE
FADES AT THE EXPENSE OF MAIN DEFORMATION BAND ARCING FROM
NORTHEAST KS INTO SOUTHWEST IA. JUST SOME LIGHT SHOWERS LEFT EAST
OF HWY 14 AS OF 09Z AND THESE WILL CONTINUE TO FADE EARLY THIS
MORNING. SURFACE ANALYSIS SHOWED LOW NEAR THE NORTHEAST
KS/NORTHWEST MO BORDER WITH NORTHWEST WINDS IN PLACE ACROSS THE
CWA ON THE BACKSIDE OF THE LOW.

THE UPPER LOW WILL LIFT INTO IA/MO TODAY...WITH SUBSIDENCE
SPREADING ACROSS THE FORECAST AREA IN WAKE OF THIS
SYSTEM....BRINGING CLEARING SKIES FROM WEST TO EAST. FORECAST
SOUNDINGS INDICATE MIXING TO AROUND 825MB TODAY...WHICH COMBINED
WITH THE DOWNSLOPE COMPONENT TO NORTHWEST WINDS...WILL SUPPORT
HIGHS IN THE UPPER 40S TO LOWER 50S. SPEAKING OF THE WINDS...THEY
WILL BE A LITTLE BLUSTERY TODAY IN THE TIGHTENED PRESSURE GRADIENT
BETWEEN THE EXITING LOW AND SURFACE HIGH OVER THE ROCKIES. THE
WINDS WILL BEGIN TO WEAKEN BY LATE AFTERNOON HOWEVER AS THE
GRADIENT RELAXES IN RESPONSE TO THE SURFACE LOW PULLING INTO
EASTERN IA/MO.

ANOTHER UPPER TROUGH WILL DIVE SOUTHEAST THROUGH THE NORTHERN PLAINS
TONIGHT...INTO THE MID MS VALLEY ON WEDNESDAY. THIS SYSTEM WILL PUSH
A COLD FRONT THROUGH THE CWA LATE TONIGHT INTO WEDNESDAY
MORNING...KNOCKING HIGHS ON WEDNESDAY BACK INTO THE LOWER 40S NORTH
TO AROUND 50F SOUTH. MOISTURE WILL BE LACKING FOR THIS SYSTEM TO
WORK WITH...HOWEVER LFQ OF 110KT UPPER JET NOSING IN...MODEST H5-H3
Q-VECTOR CONVERGENCE...AND AT LEAST SOME WEAK MID-LEVEL
FRONTOGENESIS ALL POINT TO PRETTY DECENT FORCING WITH THIS
SYSTEM...WHICH MAY BE SUFFICIENT TO SQUEEZE OUT SOME FLURRIES LATE
TONIGHT INTO WEDNESDAY MORNING DESPITE THE LACK OF AVAILABLE
MOISTURE. HENCE INSERTED ISOLATED FLURRIES IN THE NORTH AFTER
MIDNIGHT TONIGHT...WORKING SOUTH WEDNESDAY MORNING. IT WILL BE
BRISK AGAIN ON WEDNESDAY AS NORTHWEST WINDS BLOW BEHIND THE FRONT.

A NORTHWEST FLOW ALOFT TAKES HOLD OF THE AREA WEDNESDAY NIGHT INTO
THANKSGIVING DAY IN BETWEEN THIS LOW WHICH PUSHES EAST...AND AN
UPPER RIDGE THAT SHIFTS EASTWARD OVER THE ROCKIES ON THANKSGIVING.
THIS SUBSIDENT PATTERN WILL BRING DRY CONDITIONS...MOSTLY SUNNY
SKIES...AND ABOVE AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 40S
TO LOWER 50S ON THANKSGIVING. THE UPPER RIDGE SHIFTS EAST OVER THE
PLAINS ON FRIDAY...BRINGING MILD TEMPS AND CONTINUED DRY WEATHER.
THE NEXT UPPER TROUGH DIGS OVER THE WESTERN CONUS ON SATURDAY. STILL
A LOT OF MODEL DIFFERENCES REGARDING THIS SYSTEM AS IT ADVANCES
EASTWARD...AND MADE NO CHANGES TO THESE OUTER PERIODS...BUT IT WILL
BE A SYSTEM TO KEEP AN EYE ON AS WE HEAD LATER INTO THE WEEKEND
ESPECIALLY INTO EARLY NEXT WEEK.

&&

.AVIATION...06Z KGRI TAF. EXPECT CONDITIONS WILL GRADUALLY IMPROVE
THROUGH THE NIGHT WITH PRECIPITATION COMING TO AN END AND CEILINGS
RISING. SHOULD BE BACK TO VFR CONDITIONS BY DAYBREAK WITH CLEARING
SKIES MID TO LATE MORNING. THE BIGGEST CONCERN WILL BE THE WINDS
WHICH COULD BE GUSTY AT TIMES OUT OF THE NORTHWEST. WIND GUSTS OF
30 MPH OR HIGHER WILL BE POSSIBLE THROUGH MUCH OF THE DAYTIME
HOURS.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

KB

000
FXUS63 KLBF 240932
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
332 AM CST TUE NOV 24 2009

.DISCUSSION...
WATER VAPOR AND PROFILER DATA SHOWING PLAINS CYCLONE MOVING INTO
NORTHEAST KANSAS...PULLING IN DRIER AIR AND CLEARING SKIES ACROSS
WESTERN AND CENTRAL NEBRASKA. NEXT SYSTEM IS QUICKLY PROGRESSING
ACROSS CANDIAN ROCKIES AND WILL BE DROPPING INTO DAKOTA BY THIS
EVENING AND INTO WESTERN GREAT LAKES BY 48 HRS. THIS CLIPPER WILL
PUSH COLD FRONT THROUGH CWA OVERNIGHT ALONG WITH PLENTY OF MID LEVEL
MOISTURE. PCPN NOT REALLY OF A CONCERN AS LIFT THROUGH DENDRITIC
LAYER IS MINIMAL AND FAIRLY DRY LOWER LAYERS WILL BE HARD TO
SATURATE. LOOKING AT MODEL BUFKIT DATA MOST LIKELY OUTCOME WITH THE
STRONG CAA WILL BE FLURRIES ALONG WITH INCREASING WINDS. ONLY PLACE
MEASUREABLE PCPN MAY BE POSSIBLE IS DOWNSTREAM FROM HILLS IN NW FLOW
COUPLING WITH UPPER JET AXIS ALOFT AND LOW POPS RETAINED. MAIN
CONCERN LOOKS TO BE WINDY CONDITIONS SETTING UP ACROSS AT LEAST
NORTHEAST HALF OF CWA WEDNESDAY AROUND SUNRISE. WIND ADVISORY
CRITERIA DOES NOT LOOK TO BE MET ATTM WITH TIMING OF STRONGEST CAA
PRIOR TO SUNRISE AND A RATHER WEAK PRESS CHANGE COUPLET. SOMETHING
TO BE WATCHED THE NEXT FEW RUNS BUT WILL HAVE WINDY WORDING IN FCST.
FEEL BC MOSGUIDE LOOKING GOOD AND STARTED WITH THIS WITH A FEW
TWEAKS...BASICALLY MID AND UPPER 40S TODAY COOLING TO LOWER 40S FOR
WEDNESDAY. AS CLIPPER REINFORCES TROF AND DIGS ACROSS EASTERN
CONUS...NEXT SYSTEM PUSHING TOWARD NW COAST AND ALLOWS RIDGE TO
AMPLIFY ACROSS ROCKIES THURSDAY AND MOVE INTO PLAINS ON FRIDAY. AS A
RESULT NICE LATE WEEK WARMUP WILL BE ON TAP BEFORE THIS WESTERN
SYTEM MOVES INTO PLAINS AND DRAGS IN SOME RATHER COLD AIR FOR LATE
WEEKEND. SOME MODEL SOLNS SHOWING PCPN IN VCNTY OF CWA SAT/SAT NIGHT
WITH PROGRESSING OF THE NEXT TROF BUT CONFIDENCE TOO LOW THIS FAR
OUT TO INTRODUCE ANYTHING BUT CLOUD COVER.


&&

.AVIATION...
THE KLBF AND KVTN TERMINALS WILL BE BETWEEN SYSTEMS TODAY WITH
MAINLY CLEAR SKIES AND UNLIMITED VISIBILITIES EXPECTED. LOOK FOR
INCREASING HIGH LEVEL CLOUDINESS THIS AFTERNOON AT BOTH THE KLBF AND
KVTN TERMINALS AS AN UPPER LEVEL DISTURBANCE LIFTS ACROSS THE
DAKOTAS. THIS DISTURBANCE WILL PUSH A COLD FRONT THROUGH WESTERN AND
NORTH CENTRAL NEBRASKA TONIGHT. THOUGH PRECIPITATION IS NOT EXPECTED
WITH THE FRONT...MVFR CEILINGS AND GUSTY NORTHWESTERLY WINDS WILL
ACCOMPANY THE FRONTAL PASSAGE. CEILINGS RANGING FROM 1000 TO 2000 FT
AGL AND NORTHWESTERLY WINDS GUSTING UP TO 20 KTS WILL ARRIVE DURING
THE 05Z TO 08Z TIME FRAME AT KVTN AND DURING THE 07Z TO 10Z TIME
FRAME AT KLBF.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

13/CLB

000
FXUS63 KOAX 240836
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
236 AM CST TUE NOV 24 2009

.DISCUSSION...

WV LOOP SHOWING MAIN CIRCULATION OVER NORTHEAST KANSAS AT 07Z WITH
SOME CONVECTION IN ADVANCE OF MID LEVEL SPEED MAX OVER THE
SOUTHERN PLAINS FROM NORTHEAST KANSAS INTO WESTERN IOWA.

TWO AREAS OF PRECIP SHOWING UP ON RADAR AT 07Z WITH MAIN FOCUS
OVER SOUTHEAST NEBRASKA INTO SOUTHWEST IOWA. MODELS SEEM TO BE
HANDLING THE AREAL EXTENT OF THIS HEAVIER PRECIP VERY WELL AS THE
UPPER WAVE LIFTS ACROSS THE REGION TODAY. LITTLE NEED TO CHANGE CURRENT
FORECAST FOR TODAY WITH CATEGORICAL POPS ALONG THE EASTERN BORDER
OF NEBRASKA INTO SOUTHWEST IOWA. RAIN EXPECTED TO END DURING THE
AFTERNOON FOR MOST EASTERN AREAS WITH SHARP CUTOFF TO THE PRECIP.
TEMPERATURES APPEAR WARM ENOUGH TO PRECLUDE ANY SNOW TODAY.

MAIN SURGE OF COLD AIR COMES IN BEHIND THIS INITIAL WAVE TONIGHT INTO
WEDNESDAY AS SECONDARY WAVE DROPS OUT OF CENTRAL CANADA. JUST
MENTIONED FLURRIES ON WEDNESDAY WITH THIS SYSTEM AS MAIN
CIRCULATION TRACKS EAST OF THE AREA. COLD WEDNESDAY INTO THURSDAY THEN
WARMING UP AS RIDGING DEVELOPS OVER THE PLAINS REGION.

PATTERN REMAINS ACTIVE IN THE EXTENDED PERIOD AS SERIES OF WAVES
DROP INTO THE WESTERN CONUS UNDER SPLIT FLOW. ECMWF MORE EXUBERANT
OF THE MODELS WITH SYSTEM LATE IN THE PERIOD. NO CHANGES AT THIS
TIME TO THE EXTENDED PERIOD.

&&

.AVIATION...
TAF SITES KOFK/KOMA/KLNK

06Z TAFS

DEFORMATION BAND THAT SET UP EARLIER ACROSS THE KOFK TAF SITE WILL
CONTINUE TO DIMINISH...WITH -SHRA ENDING THERE BEFORE 11Z AND MVFR
CIGS BCMG VFR THEREAFTER. KLNK/KOMA WILL BE ON THE WESTERN/NORTHERN
EDGE OF THE SECOND DEFORMATION BAND THAT IS SETTING UP JUST SOUTH OF
THESE TAF SITES. MVFR CONDITIONS WITH -SHRA WILL PREVAIL THROUGH
MUCH OF THE MORNING...ALTHOUGH IMPROVING CONDITIONS WITH -SHRA
ENDING AND CIGS GOING BACK TO VFR ARE FORECAST AT KLNK BY 17Z...AND
AT KOMA BY 22Z-01Z. GUSTY NORTHWESTERLY WINDS TO 20-28KTS ARE
FORECAST AT ALL TAF SITES THROUGH THE DAY...BUT WITH GUSTS ENDING BY
23Z ACROSS THE AREA.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$

FOBERT/DEWALD

000
FXUS63 KGID 240501
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1101 PM CST MON NOV 23 2009

.AVIATION...06Z KGRI TAF. EXPECT CONDITIONS WILL GRADUALLY IMPROVE
THROUGH THE NIGHT WITH PRECIPITATION COMING TO AN END AND CEILINGS
RISING. SHOULD BE BACK TO VFR CONDITIONS BY DAYBREAK WITH CLEARING
SKIES MID TO LATE MORNING. THE BIGGEST CONCERN WILL BE THE WINDS
WHICH COULD BE GUSTY AT TIMES OUT OF THE NORTHWEST. WIND GUSTS OF
30 MPH OR HIGHER WILL BE POSSIBLE THROUGH MUCH OF THE DAYTIME
HOURS.

&&

.PREV DISCUSSION... /ISSUED 948 PM CST MON NOV 23 2009/

UPDATE...SFC TEMPERATURES ACROSS THE CWA RANGE FROM 37 TO 45
DEGREES AND CONTINUE TO BE TOO WARM FOR SNOW. THE COLD AIR IS SLOW
TO WORK INTO THIS SYSTEM AND ALTHOUGH THERE COULD STILL BE A
CHANGE OVER TO SNOW BEFORE ENDING...EXPECT LITTLE TO NO
ACCUMULATION. THE DURATION OF SNOW AFTER CHANGE OVER WOULD BE VERY
BRIEF...RIGHT AT THE TAIL END OF THE PRECIPITATION. THE RAIN COULD
CHANGE OVER TO SNOW AS THE SFC TEMPERATURES FALL INTO THE 33 TO
36 DEGREE RANGE...BUT IT WOULD BE DIFFICULT FOR SNOW TO ACCUMULATE
AT THESE TEMPERATURES. CONSEQUENTLY...THE EXPECTATION IS THAT WE
WILL SEE LITTLE TO NO SNOWFALL ACCUMULATION ACROSS OUR CWA TONIGHT.


PREV DISCUSSION... /ISSUED 338 PM CST MON NOV 23 2009/

SHORT TERM...BIGGEST FORECAST CHALLENGE WILL BE DETERMINING WHEN
AND IF PRECIPITATION CHANGES TO SNOW TONIGHT AND SUBSEQUENTLY HOW
MUCH SNOW WILL FALL.

UPPER LEVEL WATER VAPOR LOOP SHOWS A WELL-DEFINED UPPER LEVEL TROUGH
LOCATED OVER THE ROCKY MOUNTAINS HEADING EAST INTO THE PLAINS...WITH
A CLOSED LOW DEVELOPING WITHING THE TROUGH AXIS OVER THE CENTRAL
PLAINS TODAY...MOST LIKELY TRACKING THROUGH CENTRAL KANSAS.

SURFACE OBSERVATIONS REVEAL A COLD FRONT MOVING ACROSS THE STATE
TODAY IN ASSOCIATION WITH THE AFOREMENTIONED UPPER LEVEL TROUGH.

FOR TONIGHT...ENSEMBLES SUGGEST THAT GETTING PRECIPITATION IS PRETTY
MUCH A SURE THING. DIVERGENT Q VECTORS IN UPPER LEVELS INDICATE
VIGOROUS LARGE SCALE LIFT TONIGHT AND THAT GETTING WET IS AN ALMOST
SURE THING...CONSIDERING THE AMPLE MOISTURE AVAILABLE. THIS LIFT
TRANSLATES EAST AFTER MIDNIGHT...AND INDICATES THAT MOST
PRECIPITATION SHOULD SHUT OFF AT THE END OF THE PERIOD. COULD BE
SOME MODERATE MID-LEVEL FRONTOGENESIS ASSOCIATED WITH A DEFORMATION
AREA MAINLY IN THE WEST AND NORTHWEST TONIGHT...WHICH SHOULD ENHANCE
PRECIPITATION AMOUNTS SOMEWHAT...BUT TEMPERATURES ARE IN QUESTION
WHEN IT COMES TO SNOW AMOUNTS. THAT THIS TROUGH SINCE THE BOUNDARY
LAYER IS RELATIVELY WARM...A LOOK AT LEVELS NEAR 875 MB WOULD BE A
BETTER INDICATOR OF CHANGEOVER TO SNOW. THE NAM SUGGESTS THIS WILL
OCCUR IN THE FAR WEST/SOUTHWEST CWA ABOUT 00Z AND TRANSLATE EAST
INTO THE TRI-CITIES AREA BY 06Z OR SO...AND WILL REMAIN BETWEEN 0 AND
MINUS 1 DEGREE CELSIUS FOR THE REMAINDER OF THE NIGHT AS THINGS WIND
DOWN. THE BEST SHOT AT MEASURABLE SNOW APPEARS TO BE CLOSER TO THE
CLOSED LOW IN THE SOUTHWESTERN CWA WHEN TEMPERATURES WILL BE COLD
ENOUGH FOR SNOW. FARTHER EAST...IT APPEARS TEMPERATURES WILL NOT
COOL DOWN ENOUGH FOR MUCH SNOW. COULD GET UP TO A COUPLE OF INCHES
OF SNOW IN THE FAR SOUTHWESTERN CWA...BUT MUCH OF THIS WILL MELT ON
ROAD SURFACES...EXCEPT ON GRASSY SURFACES AND OVERPASSES WHERE IT
MAY CLING A LITTLE BETTER. HIGHEST SNOWFALL TOTALS WILL BE NEAR 2
INCHES IN THE FAR SOUTHWESTERN CWA TOWARD ROOKS COUNTY. AS FAR AS
WIND GOES...PRESSURE RISES AND LOW-LEVEL LAPSE RATES SUGGEST WE WILL
NOT GET WIND ADVISORY CRITERIA...EVEN IN THE FAR SOUTHWEST. WOULD BE
TOUGH TO ACHIEVE ANY SUSTAINED WIND SPEEDS MORE THAN ABOUT 23 KTS IN
THE SOUTHWEST. WHERE THE THIS SUGGESTS A POSSIBLE RAIN/SNOW MIX OR
WHEN IT DOES CHANGE TO SNOW...GETTING ANYTHING ABOVE AN INCH WOULD
BE VERY DIFFICULT. MUCAPES AND MID-LEVEL LAPSE RATES SUGGEST
POSSIBLE SOME ISOLATED THUNDER MAINLY TO THE EAST OF THE CWA TONIGHT
AND DO NOT PLAN TO MENTION THUNDER AT THIS TIME.

FOR TUESDAY...THE ISSUE WILL BE WIND SPEEDS. PRETTY GOOD SURFACE
PRESSURE GRADIENT SETS UP ON THE BACK SIDE OF THE LOW AS IT
TRANSLATES EAST AS WELL AS MIXING UP TO 850 MB WILL BE POSSIBLE
ACCORDING TO THE NAM. THIS WOULD GIVE US WIND GUSTS TO NEAR 30 MPH
FROM THE NORTHWEST. NOT WIND ADVISORY CRITERION...BUT STILL MUCH
WINDIER THAN IT HAS BE FOR SOME TIME.

FOR TUESDAY NIGHT...CONDITIONS SHOULD BE DRY AS A MID-LEVEL
SHORTWAVE RIDGE WILL BE OVERHEAD IN ADVANCE OF THE NEXT WAVE DIVING
SOUTH INTO THE NORTHERN PLAINS.

LONG TERM...12Z WEDNESDAY THROUGH MONDAY. PRIMARY FORECAST
CONCERN LIES WITH TEMPERATURES.

KEPT FORECAST DRY AT THE START OF THE LONG TERM PERIOD...THOUGH
MODELS IN PRETTY GOOD AGREEMENT SHOWING ANOTHER QUICK MOVING UPPER
LEVEL LOW PRESSURE SYSTEM IN THE REGION.  AT 12Z WEDNESDAY THIS
SYSTEM IS NEAR THE EASTERN ND/SD BOARDER...AND THROUGH THE DAY
SHIFTS TO THE SSE...ENDING UP CENTERED OVER NORTHERN IA BY 00Z
THURSDAY.  ASSOCIATED WITH THIS SYSTEM IS A REINFORCING SFC COLD
FRONT...WHICH IS EXPECTED TO CROSS THROUGH THE CWA EARLY IN THE
MORNING.  MODEL OUTPUT SHOWING AT LEAST SOME LIGHT QPF DEVELOPING
ACROSS PORTIONS OF THE CENTRAL PLAINS...EITHER ACCOMPANYING THE
SYSTEM ITSELF...OR IN RESPONSE TO MORE FAVORABLE POSITIONING OF A
STRONG +110KT UPPER LEVEL JET NOSING IN FROM THE NORTHERN PLAINS.
DID KEEP FORECAST DRY...AS THE CWA SITS IN BETWEEN THOSE MORE
FAVORABLE AREAS...AND FORECAST SOUNDINGS SHOW MUCH DRIER AREA MOVING
IN BEHIND THE SFC FRONT.  EXPECTING THE DAYTIME HOURS ON WEDNESDAY
TO ALSO BE BREEZY...WITH PRESSURE RISES/INCREASED GRADIENT AND
BETTER MIXING ACROSS THE CWA.  THINK THAT WINDS WILL REMAIN BELOW
ADV CRITERIA...WITH SUSTAINED SPEEDS NEAR 20KTS.

THANKSGIVING DAY FORECAST REMAINS DRY...AS THE CWA SITS UNDER THE
INFLUENCE OF NNW UPPER LEVEL FLOW ON THE BACKSIDE OF WEDNESDAYS
SYSTEM.  LOOKING AT THE SFC PATTERN...HIGH PRESSURE SETTLES IN
ACROSS THE REGION DURING THE DAYTIME HOURS...BRINGING GRADUALLY
DIMINISHING WINDS.  AS FAR AS HIGH TEMPERATURES GO FOR
WED/THURS...EVEN WITH A SFC COLD FRONT MOVING THROUGH...NO
SIGNIFICANT CHANGES EXPECTED...WITH HIGHS REMAINING NEAR NORMAL
GENERALLY IN THE 40S AND A FEW READINGS NEAR 50 IN THE SW ON
THURSDAY.

LOOKING TOWARD FRIDAY AND SATURDAY...MODELS IN GOOD AGREEMENT
SHOWING AN AMPLIFYING UPPER LEVEL PATTERN...WITH RIDGING BUILDING IN
OVER THE ROCKIES AS TROUGHS SIT NEAR BOTH COASTS.  EXPECTING WARMEST
DAY TO COME ON FRIDAY...WITH THE RIDGE AXIS SHIFTING OUT OF THE
ROCKIES AND ONTO THE PLAINS.  SFC WINDS BECOME SOUTHERLY AS HIGH
PRESSURE SLIDES OFF TO THE SE AND LOW PRESSURE DEVELOPS ALONG THE
FRONT RANGE.  EXPECTING PLENTY OF SUNSHINE WITH HIGHS IN THE LOWER
TO MID 50S.  ON SATURDAY...THE RIDGE AXIS CONTINUES TO SHIFT EAST
AND STARTS TO BREAK DOWN...WITH UPPER LEVEL FLOW BECOMING
SOUTHWESTERLY AS THE NEXT TROUGH MOVES THROUGH THE ROCKIES.  THIS
BRINGS SLIGHTLY COOLER TEMPS...BUT ONLY INTO THE LOWER 50S.

THINGS BECOME A BIT MORE INTERESTING AS WE GET INTO
SUNDAY/MONDAY...BUT CONFIDENCE ALSO DROPS OFF.  WHILE THE TIMING OF
THIS NEXT SYSTEM IS ACTUALLY NOT TOO BAD BETWEEN MODELS...THERE ARE
DIFFERENCE ON JUST HOW THE PATTERN EVOLVES AS THE TROUGH SHIFTS EAST
AND AN AREA OF LOW PRESSURE DEVELOPS.  BOTH THE GFS AND ECMWF DROP
ENERGY DOWN INTO THE DESERT SW...BUT THE ECMWF DEVELOPS A CLOSED LOW
AND KEEPS THE NORTHERN ENERGY AS AN OPEN TROUGH WHILE THE GFS CLOSES
THE LOW IN THE NORTHERN PLAINS AND THEN DROPS IT SOUTH ACROSS THE
CWA.  OBVIOUSLY THIS CREATES ISSUES WITH WHETHER OR NOT TO MENTION
POPS...AND DECIDED WITH THIS BEING DAY 6/7 TO LEAVE DRY UNTIL THERE
IS BETTER AGREEMENT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KGID 240348 AAA
AFDGID

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
948 PM CST MON NOV 23 2009

.UPDATE...SFC TEMPERATURES ACROSS THE CWA RANGE FROM 37 TO 45
DEGREES AND CONTINUE TO BE TOO WARM FOR SNOW. THE COLD AIR IS SLOW
TO WORK INTO THIS SYSTEM AND ALTHOUGH THERE COULD STILL BE A
CHANGE OVER TO SNOW BEFORE ENDING...EXPECT LITTLE TO NO
ACCUMULATION. THE DURATION OF SNOW AFTER CHANGE OVER WOULD BE VERY
BRIEF...RIGHT AT THE TAIL END OF THE PRECIPITATION. THE RAIN COULD
CHANGE OVER TO SNOW AS THE SFC TEMPERATURES FALL INTO THE 33 TO
36 DEGREE RANGE...BUT IT WOULD BE DIFFICULT FOR SNOW TO ACCUMULATE
AT THESE TEMPERATURES. CONSEQUENTLY...THE EXPECTATION IS THAT WE
WILL SEE LITTLE TO NO SNOWFALL ACCUMULATION ACROSS OUR CWA TONIGHT.

&&

.PREV DISCUSSION... /ISSUED 557 PM CST MON NOV 23 2009/

AVIATION...00Z KGRI TAF. A BAND OF RAIN HAS DEVELOPED IN AND
AROUND THE AIRPORT THIS EVENING AND WILL REMAIN NEARLY
STATIONARY THROUGH LATE EVENING. PERIODS OF LIGHT RAIN CAN BE
EXPECTED AT KGRI...WITH RAIN MIXING WITH SNOW BY AROUND MIDNIGHT.
SFC TEMPERATURES WILL REMAIN ABOVE FREEZING SO ANY SNOW THAT DOES
FALL SHOULD NOT ACCUMULATE TOO QUICKLY AND THEN END PRIOR TO
DAYBREAK. NORTH NORTHWEST WINDS WILL INCREASE THROUGH THE
OVERNIGHT HOURS AND BECOME GUSTY TOMORROW WITH GUSTS TO OVER 30
MPH. CLOUDS WILL GRADUALLY BREAK UP THROUGH THE MORNING WITH CLEAR
TO MOSTLY CLEAR SKIES BY AFTERNOON.

PREV DISCUSSION... /ISSUED 338 PM CST MON NOV 23 2009/

SHORT TERM...BIGGEST FORECAST CHALLENGE WILL BE DETERMINING WHEN
AND IF PRECIPITATION CHANGES TO SNOW TONIGHT AND SUBSEQUENTLY HOW
MUCH SNOW WILL FALL.

UPPER LEVEL WATER VAPOR LOOP SHOWS A WELL-DEFINED UPPER LEVEL TROUGH
LOCATED OVER THE ROCKY MOUNTAINS HEADING EAST INTO THE PLAINS...WITH
A CLOSED LOW DEVELOPING WITHING THE TROUGH AXIS OVER THE CENTRAL
PLAINS TODAY...MOST LIKELY TRACKING THROUGH CENTRAL KANSAS.

SURFACE OBSERVATIONS REVEAL A COLD FRONT MOVING ACROSS THE STATE
TODAY IN ASSOCIATION WITH THE AFOREMENTIONED UPPER LEVEL TROUGH.

FOR TONIGHT...ENSEMBLES SUGGEST THAT GETTING PRECIPITATION IS PRETTY
MUCH A SURE THING. DIVERGENT Q VECTORS IN UPPER LEVELS INDICATE
VIGOROUS LARGE SCALE LIFT TONIGHT AND THAT GETTING WET IS AN ALMOST
SURE THING...CONSIDERING THE AMPLE MOISTURE AVAILABLE. THIS LIFT
TRANSLATES EAST AFTER MIDNIGHT...AND INDICATES THAT MOST
PRECIPITATION SHOULD SHUT OFF AT THE END OF THE PERIOD. COULD BE
SOME MODERATE MID-LEVEL FRONTOGENESIS ASSOCIATED WITH A DEFORMATION
AREA MAINLY IN THE WEST AND NORTHWEST TONIGHT...WHICH SHOULD ENHANCE
PRECIPITATION AMOUNTS SOMEWHAT...BUT TEMPERATURES ARE IN QUESTION
WHEN IT COMES TO SNOW AMOUNTS. THAT THIS TROUGH SINCE THE BOUNDARY
LAYER IS RELATIVELY WARM...A LOOK AT LEVELS NEAR 875 MB WOULD BE A
BETTER INDICATOR OF CHANGEOVER TO SNOW. THE NAM SUGGESTS THIS WILL
OCCUR IN THE FAR WEST/SOUTHWEST CWA ABOUT 00Z AND TRANSLATE EAST
INTO THE TRI-CITIES AREA BY 06Z OR SO...AND WILL REMAIN BETWEEN 0 AND
MINUS 1 DEGREE CELSIUS FOR THE REMAINDER OF THE NIGHT AS THINGS WIND
DOWN. THE BEST SHOT AT MEASURABLE SNOW APPEARS TO BE CLOSER TO THE
CLOSED LOW IN THE SOUTHWESTERN CWA WHEN TEMPERATURES WILL BE COLD
ENOUGH FOR SNOW. FARTHER EAST...IT APPEARS TEMPERATURES WILL NOT
COOL DOWN ENOUGH FOR MUCH SNOW. COULD GET UP TO A COUPLE OF INCHES
OF SNOW IN THE FAR SOUTHWESTERN CWA...BUT MUCH OF THIS WILL MELT ON
ROAD SURFACES...EXCEPT ON GRASSY SURFACES AND OVERPASSES WHERE IT
MAY CLING A LITTLE BETTER. HIGHEST SNOWFALL TOTALS WILL BE NEAR 2
INCHES IN THE FAR SOUTHWESTERN CWA TOWARD ROOKS COUNTY. AS FAR AS
WIND GOES...PRESSURE RISES AND LOW-LEVEL LAPSE RATES SUGGEST WE WILL
NOT GET WIND ADVISORY CRITERIA...EVEN IN THE FAR SOUTHWEST. WOULD BE
TOUGH TO ACHIEVE ANY SUSTAINED WIND SPEEDS MORE THAN ABOUT 23 KTS IN
THE SOUTHWEST. WHERE THE THIS SUGGESTS A POSSIBLE RAIN/SNOW MIX OR
WHEN IT DOES CHANGE TO SNOW...GETTING ANYTHING ABOVE AN INCH WOULD
BE VERY DIFFICULT. MUCAPES AND MID-LEVEL LAPSE RATES SUGGEST
POSSIBLE SOME ISOLATED THUNDER MAINLY TO THE EAST OF THE CWA TONIGHT
AND DO NOT PLAN TO MENTION THUNDER AT THIS TIME.

FOR TUESDAY...THE ISSUE WILL BE WIND SPEEDS. PRETTY GOOD SURFACE
PRESSURE GRADIENT SETS UP ON THE BACK SIDE OF THE LOW AS IT
TRANSLATES EAST AS WELL AS MIXING UP TO 850 MB WILL BE POSSIBLE
ACCORDING TO THE NAM. THIS WOULD GIVE US WIND GUSTS TO NEAR 30 MPH
FROM THE NORTHWEST. NOT WIND ADVISORY CRITERION...BUT STILL MUCH
WINDIER THAN IT HAS BE FOR SOME TIME.

FOR TUESDAY NIGHT...CONDITIONS SHOULD BE DRY AS A MID-LEVEL
SHORTWAVE RIDGE WILL BE OVERHEAD IN ADVANCE OF THE NEXT WAVE DIVING
SOUTH INTO THE NORTHERN PLAINS.

LONG TERM...12Z WEDNESDAY THROUGH MONDAY. PRIMARY FORECAST
CONCERN LIES WITH TEMPERATURES.

KEPT FORECAST DRY AT THE START OF THE LONG TERM PERIOD...THOUGH
MODELS IN PRETTY GOOD AGREEMENT SHOWING ANOTHER QUICK MOVING UPPER
LEVEL LOW PRESSURE SYSTEM IN THE REGION.  AT 12Z WEDNESDAY THIS
SYSTEM IS NEAR THE EASTERN ND/SD BOARDER...AND THROUGH THE DAY
SHIFTS TO THE SSE...ENDING UP CENTERED OVER NORTHERN IA BY 00Z
THURSDAY.  ASSOCIATED WITH THIS SYSTEM IS A REINFORCING SFC COLD
FRONT...WHICH IS EXPECTED TO CROSS THROUGH THE CWA EARLY IN THE
MORNING.  MODEL OUTPUT SHOWING AT LEAST SOME LIGHT QPF DEVELOPING
ACROSS PORTIONS OF THE CENTRAL PLAINS...EITHER ACCOMPANYING THE
SYSTEM ITSELF...OR IN RESPONSE TO MORE FAVORABLE POSITIONING OF A
STRONG +110KT UPPER LEVEL JET NOSING IN FROM THE NORTHERN PLAINS.
DID KEEP FORECAST DRY...AS THE CWA SITS IN BETWEEN THOSE MORE
FAVORABLE AREAS...AND FORECAST SOUNDINGS SHOW MUCH DRIER AREA MOVING
IN BEHIND THE SFC FRONT.  EXPECTING THE DAYTIME HOURS ON WEDNESDAY
TO ALSO BE BREEZY...WITH PRESSURE RISES/INCREASED GRADIENT AND
BETTER MIXING ACROSS THE CWA.  THINK THAT WINDS WILL REMAIN BELOW
ADV CRITERIA...WITH SUSTAINED SPEEDS NEAR 20KTS.

THANKSGIVING DAY FORECAST REMAINS DRY...AS THE CWA SITS UNDER THE
INFLUENCE OF NNW UPPER LEVEL FLOW ON THE BACKSIDE OF WEDNESDAYS
SYSTEM.  LOOKING AT THE SFC PATTERN...HIGH PRESSURE SETTLES IN
ACROSS THE REGION DURING THE DAYTIME HOURS...BRINGING GRADUALLY
DIMINISHING WINDS.  AS FAR AS HIGH TEMPERATURES GO FOR
WED/THURS...EVEN WITH A SFC COLD FRONT MOVING THROUGH...NO
SIGNIFICANT CHANGES EXPECTED...WITH HIGHS REMAINING NEAR NORMAL
GENERALLY IN THE 40S AND A FEW READINGS NEAR 50 IN THE SW ON
THURSDAY.

LOOKING TOWARD FRIDAY AND SATURDAY...MODELS IN GOOD AGREEMENT
SHOWING AN AMPLIFYING UPPER LEVEL PATTERN...WITH RIDGING BUILDING IN
OVER THE ROCKIES AS TROUGHS SIT NEAR BOTH COASTS.  EXPECTING WARMEST
DAY TO COME ON FRIDAY...WITH THE RIDGE AXIS SHIFTING OUT OF THE
ROCKIES AND ONTO THE PLAINS.  SFC WINDS BECOME SOUTHERLY AS HIGH
PRESSURE SLIDES OFF TO THE SE AND LOW PRESSURE DEVELOPS ALONG THE
FRONT RANGE.  EXPECTING PLENTY OF SUNSHINE WITH HIGHS IN THE LOWER
TO MID 50S.  ON SATURDAY...THE RIDGE AXIS CONTINUES TO SHIFT EAST
AND STARTS TO BREAK DOWN...WITH UPPER LEVEL FLOW BECOMING
SOUTHWESTERLY AS THE NEXT TROUGH MOVES THROUGH THE ROCKIES.  THIS
BRINGS SLIGHTLY COOLER TEMPS...BUT ONLY INTO THE LOWER 50S.

THINGS BECOME A BIT MORE INTERESTING AS WE GET INTO
SUNDAY/MONDAY...BUT CONFIDENCE ALSO DROPS OFF.  WHILE THE TIMING OF
THIS NEXT SYSTEM IS ACTUALLY NOT TOO BAD BETWEEN MODELS...THERE ARE
DIFFERENCE ON JUST HOW THE PATTERN EVOLVES AS THE TROUGH SHIFTS EAST
AND AN AREA OF LOW PRESSURE DEVELOPS.  BOTH THE GFS AND ECMWF DROP
ENERGY DOWN INTO THE DESERT SW...BUT THE ECMWF DEVELOPS A CLOSED LOW
AND KEEPS THE NORTHERN ENERGY AS AN OPEN TROUGH WHILE THE GFS CLOSES
THE LOW IN THE NORTHERN PLAINS AND THEN DROPS IT SOUTH ACROSS THE
CWA.  OBVIOUSLY THIS CREATES ISSUES WITH WHETHER OR NOT TO MENTION
POPS...AND DECIDED WITH THIS BEING DAY 6/7 TO LEAVE DRY UNTIL THERE
IS BETTER AGREEMENT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KOAX 240333
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
933 PM CST MON NOV 23 2009

.DISCUSSION...

UPPR LVL SYSTEM PRETTY MUCH EVOLVING AS FORECAST. 00Z UPPR AIR
ANLYS INDCD 90 KT H3 JET MOVG THRU CNTRL KS. UPSTREAM ANOTHER 95
KT H3 JET WAS DIVING THRU WRN CO. INITIAL H5 CLOSED LO WAS LOCATED
OVR NW KS...BUT H5 THERMAL TROF WAS LAGGING AND WAS OVR NRN CO AT
00Z. H85 ANLYS INDCD LO NR CNK WITH CDFNT INTO THE SRN PLAINS.
INVERTED TROF EXTNDD NWD THRU ERN NEB. H85 0 C ISOTHERM EXTNDD FM
ERN SD INTO WRN NEB NR KLBF.

AS UPSTREAM 95 KT H3 JET DIVES INTO THE BASE OF TROF...H5 LO IS
EXPECTED TO REDEVELOP OVR SRN KS OVERNIGHT AND THEN EJECT NEWD
THRU NE KS INTO NRN MO DURING THE DAY ON TUES. INITIAL BAND OF
PRECIP /ASSOCIATED WITH H8 THERMAL GRADIENT FM NE NEB INTO NW KS/
IS EXPECTED TO WEAKEN OVERNIGHT AS BETTER FOCUS SHIFTS FARTHER S
WITH REDEVELOPING CLOSED LOW OVR SRN KS. THUS HAVE UPDATED TO
REMOVE POPS AFTER 09Z OVR THE NW CWA. COMPARISON OF THE NAM/GFS 6
HR FORECAST SOUNDINGS WITH THE 00Z RAOB FM THE AREA INDCS THE NAM
HAD A BETTER HANDLE ON THE THERMAL/MOISTURE PROFILE CURRENTLY.
THIS SEEMED TO ALSO BE TRUE OF THE 00Z NAM AS WELL. THUS HAVE USED
THIS FOR POINT FORECAST SOUNDINGS FOR THE NEXT 24 HOURS. MODIFYING
SFC TMPS FOR THE NIGHT AND USING THE NEW POINT SOUNDINGS INDCS
LITTLE CHC OF PRECIP ACTUALLY SWITCHING OVR TO SNOW DESPITE SUCH A
STG SYSTEM. THUS HAVE REMOVED SN MENTION FM THE GRIDS AND ANY
ACCUM WE HAD GOING. HAVE DONE THE SAME FOR TUES AS WELL OVR THE
CWA. DID INCREASE GOING POPS ALNG THE MO RIVER AND POINTS E ON
TUES AS THIS AREA SHLD BE WITHIN THE E-W DEFORMATION ZONE /TROWAL/
AREA AS THE SYSTEM MOVES INTO IA.

NEW GRIDS/ZFP WL BE OUT BY 10 PM.

BOUSTEAD

&&

.PREV DISCUSSION... /ISSUED 311 PM CST MON NOV 23 2009/

SHORT TERM...TONIGHT THROUGH THURSDAY.

WV IMAGERY SHOWING INITIAL SHORTWAVE TROF OF INTEREST WAS SITUATED
OVER THE CNTRL CONUS WITH ANOTHER WAVE UPSTREAM COMING ASHORE OVER
WRN CANADA.

GOOD AGREEMENT THAT MAX OMEGA PHASES WELL WITH MID/UPR QVECT
CONVERGENCE AND DEEP LYR MOISTURE OVER THE CWA TONIGHT AS INITIAL
UPPER LEVEL TROF GRADUALLY TRACKS EAST OVER THE REGION. SFC
REFLECTION WILL STRENGTHEN DURING THIS TIME OVER KANSAS AND DRAG A
COLD FRONT DEEP INTO THE CNTRL/SRN PLAINS. THE QUICK MOVING BOUNDARY
IS PROGGED TO BE PUSHING ACROSS WRN MO/WRN AR/ERN TX BY 12Z TUES. AT
THAT TIME MODELS TAKE THE BRUNT OF DYNAMIC FORCING INTO THE MID MS
VLY...HOWEVER CANNOT RULE OUT LINGERING ACTIVITY THRU TUESDAY AFTN ON
THE BACKSIDE OF THE EXITING SYSTEM. AS FOR PCPN TYPE...AM SEEING
LITTLE PER COBB BUFKIT DATA/CRITICAL THKNS TO SUGGEST ANYTHING MORE
THAN A POTENTIAL FOR RA/SN MIX LATE TONIGHT OVER NORTHEAST NEB. COME
TUESDAY NIGHT...THE NEXT SHORTWAVE TROF OF CONCERN DROPS DOWN THRU
THE DAKOTAS/MN WITH ACCOMPANYING SECONDARY SHOT OF COLD AIR FUNNELING
SWD. AGAIN...VERY STRONG LIFT WITH THIS SECOND WAVE AND RE-ENFORCING
COLD AIRMASS BUT WITH LITTLE MOISTURE TO TAP INTO EXPECT DRY FROPA.
OTHERWISE...THE SERIES SFC COLD FRONT MOVING THRU ARE RELATIVELY WEAK
AND ANTICIPATE RESULT WILL BE ONLY SLIGHTLY BELOW NORMAL AFTN HIGHS
TUES-THURS.

LONG TERM...THURSDAY NIGHT THROUGH MONDAY.

MODELS ARE IN VERY GOOD AGREEMENT WITH THE LARGE SCALE PATTERN AT
THE START OF THIS PERIOD. THEY SHOW ONE TROUGH ENTERING THE WEST
COAST FROM CNTRL CA NORTHWARD AND ANOTHER OVER THE ERN U.S. AT 00Z
FRIDAY. OUR AREA IS IN NORTHWEST FLOW...WITH A RIDGE OVER THE
ROCKIES AND HIGH PLAINS. THE PATTERN WILL BE PROGRESSIVE...WITH A
BROAD TROUGH OVER THE ROCKIES AND MUCH OF THE PLAINS BY LATE
SATURDAY. TWO DIFFERENT UPPER LEVEL LOWS DEVELOP OVER THE WEEKEND.
ONE WILL DIG OVER THE FOUR CORNERS REGION...WHILE ANOTHER DEVELOPS
OVER THE NORTHERN PLAINS.

IN REGARDS TO THE NORTHERN PLAINS SYSTEM...THE 12Z GFS APPEARS TO
BE A COMPROMISE OF THE 12Z CANADIAN GEM AND THE 12Z ECMWF. THE GEM
DEVELOPS PCPN FROM THE EASTERN DAKOTA AND MINNESOTA SOUTHWARD INTO
EASTERN NEBRASKA SATURDAY. THE 12Z GFS IS MAINLY DRY FOR OUR AREA
UNTIL SUNDAY NIGHT OR MONDAY...WHEN IT SUGGESTS SOME LIGHT SNOW.
THE 00Z AND 12Z ECWWF WERE MAINLY DRY.

EXPECT LOWS DURING THIS PERIOD IN THE 20S TO LOWER 30S AND HIGHS IN
THE 40S TO LOWER 50S.

AVIATION...
TAF SITES KOFK/KOMA/KLNK

18Z TAFS

SFC LOW PRESSURE OVER WESTERN OKLAHOMA WL CONTINUE TO MOVE NEWD
OVERNIGHT AND TOWARD SERN NEB BY 06Z TONIGHT. PCPN IS EXPECTED TO
MOVE TOWARD TAF SITES LATER THIS EVENING AND MAINLY IN THE FORM OF
RAIN. SOME SNOW COULD MIX IN OVERNIGHT AROUND KOFK...BUT CHANCES ARE
SO SLIM THAT WL NOT MENTION AT THIS POINT. PCPN IS EXPECTED TO
CONTINUE OVERNIGHT AND BEGIN TO TAPER OFF BY MORNING. GUSTY NW WINDS
ARE EXPECTED AS WELL. CIGS SHOULD VARY BETWEEN MVFR AND IFR THRU
MUCH OF THE PD.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

$$

000
FXUS63 KGID 232357
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
557 PM CST MON NOV 23 2009

.AVIATION...00Z KGRI TAF. A BAND OF RAIN HAS DEVELOPED IN AND
AROUND THE AIRPORT THIS EVENING AND WILL REMAIN NEARLY
STATIONARY THROUGH LATE EVENING. PERIODS OF LIGHT RAIN CAN BE
EXPECTED AT KGRI...WITH RAIN MIXING WITH SNOW BY AROUND MIDNIGHT.
SFC TEMPERATURES WILL REMAIN ABOVE FREEZING SO ANY SNOW THAT DOES
FALL SHOULD NOT ACCUMULATE TOO QUICKLY AND THEN END PRIOR TO
DAYBREAK. NORTH NORTHWEST WINDS WILL INCREASE THROUGH THE
OVERNIGHT HOURS AND BECOME GUSTY TOMORROW WITH GUSTS TO OVER 30
MPH. CLOUDS WILL GRADUALLY BREAK UP THROUGH THE MORNING WITH CLEAR
TO MOSTLY CLEAR SKIES BY AFTERNOON.

&&

.PREV DISCUSSION... /ISSUED 338 PM CST MON NOV 23 2009/

SHORT TERM...BIGGEST FORECAST CHALLENGE WILL BE DETERMINING WHEN
AND IF PRECIPITATION CHANGES TO SNOW TONIGHT AND SUBSEQUENTLY HOW
MUCH SNOW WILL FALL.

UPPER LEVEL WATER VAPOR LOOP SHOWS A WELL-DEFINED UPPER LEVEL TROUGH
LOCATED OVER THE ROCKY MOUNTAINS HEADING EAST INTO THE PLAINS...WITH
A CLOSED LOW DEVELOPING WITHING THE TROUGH AXIS OVER THE CENTRAL
PLAINS TODAY...MOST LIKELY TRACKING THROUGH CENTRAL KANSAS.

SURFACE OBSERVATIONS REVEAL A COLD FRONT MOVING ACROSS THE STATE
TODAY IN ASSOCIATION WITH THE AFOREMENTIONED UPPER LEVEL TROUGH.

FOR TONIGHT...ENSEMBLES SUGGEST THAT GETTING PRECIPITATION IS PRETTY
MUCH A SURE THING. DIVERGENT Q VECTORS IN UPPER LEVELS INDICATE
VIGOROUS LARGE SCALE LIFT TONIGHT AND THAT GETTING WET IS AN ALMOST
SURE THING...CONSIDERING THE AMPLE MOISTURE AVAILABLE. THIS LIFT
TRANSLATES EAST AFTER MIDNIGHT...AND INDICATES THAT MOST
PRECIPITATION SHOULD SHUT OFF AT THE END OF THE PERIOD. COULD BE
SOME MODERATE MID-LEVEL FRONTOGENESIS ASSOCIATED WITH A DEFORMATION
AREA MAINLY IN THE WEST AND NORTHWEST TONIGHT...WHICH SHOULD ENHANCE
PRECIPITATION AMOUNTS SOMEWHAT...BUT TEMPERATURES ARE IN QUESTION
WHEN IT COMES TO SNOW AMOUNTS. THAT THIS TROUGH SINCE THE BOUNDARY
LAYER IS RELATIVELY WARM...A LOOK AT LEVELS NEAR 875 MB WOULD BE A
BETTER INDICATOR OF CHANGEOVER TO SNOW. THE NAM SUGGESTS THIS WILL
OCCUR IN THE FAR WEST/SOUTHWEST CWA ABOUT 00Z AND TRANSLATE EAST
INTO THE TRI-CITIES AREA BY 06Z OR SO...AND WILL REMAIN BETWEEN 0 AND
MINUS 1 DEGREE CELSIUS FOR THE REMAINDER OF THE NIGHT AS THINGS WIND
DOWN. THE BEST SHOT AT MEASURABLE SNOW APPEARS TO BE CLOSER TO THE
CLOSED LOW IN THE SOUTHWESTERN CWA WHEN TEMPERATURES WILL BE COLD
ENOUGH FOR SNOW. FARTHER EAST...IT APPEARS TEMPERATURES WILL NOT
COOL DOWN ENOUGH FOR MUCH SNOW. COULD GET UP TO A COUPLE OF INCHES
OF SNOW IN THE FAR SOUTHWESTERN CWA...BUT MUCH OF THIS WILL MELT ON
ROAD SURFACES...EXCEPT ON GRASSY SURFACES AND OVERPASSES WHERE IT
MAY CLING A LITTLE BETTER. HIGHEST SNOWFALL TOTALS WILL BE NEAR 2
INCHES IN THE FAR SOUTHWESTERN CWA TOWARD ROOKS COUNTY. AS FAR AS
WIND GOES...PRESSURE RISES AND LOW-LEVEL LAPSE RATES SUGGEST WE WILL
NOT GET WIND ADVISORY CRITERIA...EVEN IN THE FAR SOUTHWEST. WOULD BE
TOUGH TO ACHIEVE ANY SUSTAINED WIND SPEEDS MORE THAN ABOUT 23 KTS IN
THE SOUTHWEST. WHERE THE THIS SUGGESTS A POSSIBLE RAIN/SNOW MIX OR
WHEN IT DOES CHANGE TO SNOW...GETTING ANYTHING ABOVE AN INCH WOULD
BE VERY DIFFICULT. MUCAPES AND MID-LEVEL LAPSE RATES SUGGEST
POSSIBLE SOME ISOLATED THUNDER MAINLY TO THE EAST OF THE CWA TONIGHT
AND DO NOT PLAN TO MENTION THUNDER AT THIS TIME.

FOR TUESDAY...THE ISSUE WILL BE WIND SPEEDS. PRETTY GOOD SURFACE
PRESSURE GRADIENT SETS UP ON THE BACK SIDE OF THE LOW AS IT
TRANSLATES EAST AS WELL AS MIXING UP TO 850 MB WILL BE POSSIBLE
ACCORDING TO THE NAM. THIS WOULD GIVE US WIND GUSTS TO NEAR 30 MPH
FROM THE NORTHWEST. NOT WIND ADVISORY CRITERION...BUT STILL MUCH
WINDIER THAN IT HAS BE FOR SOME TIME.

FOR TUESDAY NIGHT...CONDITIONS SHOULD BE DRY AS A MID-LEVEL
SHORTWAVE RIDGE WILL BE OVERHEAD IN ADVANCE OF THE NEXT WAVE DIVING
SOUTH INTO THE NORTHERN PLAINS.

LONG TERM...12Z WEDNESDAY THROUGH MONDAY. PRIMARY FORECAST
CONCERN LIES WITH TEMPERATURES.

KEPT FORECAST DRY AT THE START OF THE LONG TERM PERIOD...THOUGH
MODELS IN PRETTY GOOD AGREEMENT SHOWING ANOTHER QUICK MOVING UPPER
LEVEL LOW PRESSURE SYSTEM IN THE REGION.  AT 12Z WEDNESDAY THIS
SYSTEM IS NEAR THE EASTERN ND/SD BOARDER...AND THROUGH THE DAY
SHIFTS TO THE SSE...ENDING UP CENTERED OVER NORTHERN IA BY 00Z
THURSDAY.  ASSOCIATED WITH THIS SYSTEM IS A REINFORCING SFC COLD
FRONT...WHICH IS EXPECTED TO CROSS THROUGH THE CWA EARLY IN THE
MORNING.  MODEL OUTPUT SHOWING AT LEAST SOME LIGHT QPF DEVELOPING
ACROSS PORTIONS OF THE CENTRAL PLAINS...EITHER ACCOMPANYING THE
SYSTEM ITSELF...OR IN RESPONSE TO MORE FAVORABLE POSITIONING OF A
STRONG +110KT UPPER LEVEL JET NOSING IN FROM THE NORTHERN PLAINS.
DID KEEP FORECAST DRY...AS THE CWA SITS IN BETWEEN THOSE MORE
FAVORABLE AREAS...AND FORECAST SOUNDINGS SHOW MUCH DRIER AREA MOVING
IN BEHIND THE SFC FRONT.  EXPECTING THE DAYTIME HOURS ON WEDNESDAY
TO ALSO BE BREEZY...WITH PRESSURE RISES/INCREASED GRADIENT AND
BETTER MIXING ACROSS THE CWA.  THINK THAT WINDS WILL REMAIN BELOW
ADV CRITERIA...WITH SUSTAINED SPEEDS NEAR 20KTS.

THANKSGIVING DAY FORECAST REMAINS DRY...AS THE CWA SITS UNDER THE
INFLUENCE OF NNW UPPER LEVEL FLOW ON THE BACKSIDE OF WEDNESDAYS
SYSTEM.  LOOKING AT THE SFC PATTERN...HIGH PRESSURE SETTLES IN
ACROSS THE REGION DURING THE DAYTIME HOURS...BRINGING GRADUALLY
DIMINISHING WINDS.  AS FAR AS HIGH TEMPERATURES GO FOR
WED/THURS...EVEN WITH A SFC COLD FRONT MOVING THROUGH...NO
SIGNIFICANT CHANGES EXPECTED...WITH HIGHS REMAINING NEAR NORMAL
GENERALLY IN THE 40S AND A FEW READINGS NEAR 50 IN THE SW ON
THURSDAY.

LOOKING TOWARD FRIDAY AND SATURDAY...MODELS IN GOOD AGREEMENT
SHOWING AN AMPLIFYING UPPER LEVEL PATTERN...WITH RIDGING BUILDING IN
OVER THE ROCKIES AS TROUGHS SIT NEAR BOTH COASTS.  EXPECTING WARMEST
DAY TO COME ON FRIDAY...WITH THE RIDGE AXIS SHIFTING OUT OF THE
ROCKIES AND ONTO THE PLAINS.  SFC WINDS BECOME SOUTHERLY AS HIGH
PRESSURE SLIDES OFF TO THE SE AND LOW PRESSURE DEVELOPS ALONG THE
FRONT RANGE.  EXPECTING PLENTY OF SUNSHINE WITH HIGHS IN THE LOWER
TO MID 50S.  ON SATURDAY...THE RIDGE AXIS CONTINUES TO SHIFT EAST
AND STARTS TO BREAK DOWN...WITH UPPER LEVEL FLOW BECOMING
SOUTHWESTERLY AS THE NEXT TROUGH MOVES THROUGH THE ROCKIES.  THIS
BRINGS SLIGHTLY COOLER TEMPS...BUT ONLY INTO THE LOWER 50S.

THINGS BECOME A BIT MORE INTERESTING AS WE GET INTO
SUNDAY/MONDAY...BUT CONFIDENCE ALSO DROPS OFF.  WHILE THE TIMING OF
THIS NEXT SYSTEM IS ACTUALLY NOT TOO BAD BETWEEN MODELS...THERE ARE
DIFFERENCE ON JUST HOW THE PATTERN EVOLVES AS THE TROUGH SHIFTS EAST
AND AN AREA OF LOW PRESSURE DEVELOPS.  BOTH THE GFS AND ECMWF DROP
ENERGY DOWN INTO THE DESERT SW...BUT THE ECMWF DEVELOPS A CLOSED LOW
AND KEEPS THE NORTHERN ENERGY AS AN OPEN TROUGH WHILE THE GFS CLOSES
THE LOW IN THE NORTHERN PLAINS AND THEN DROPS IT SOUTH ACROSS THE
CWA.  OBVIOUSLY THIS CREATES ISSUES WITH WHETHER OR NOT TO MENTION
POPS...AND DECIDED WITH THIS BEING DAY 6/7 TO LEAVE DRY UNTIL THERE
IS BETTER AGREEMENT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KGID 232138
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
338 PM CST MON NOV 23 2009

.SHORT TERM...BIGGEST FORECAST CHALLENGE WILL BE DETERMINING WHEN
AND IF PRECIPITATION CHANGES TO SNOW TONIGHT AND SUBSEQUENTLY HOW
MUCH SNOW WILL FALL.

UPPER LEVEL WATER VAPOR LOOP SHOWS A WELL-DEFINED UPPER LEVEL TROUGH
LOCATED OVER THE ROCKY MOUNTAINS HEADING EAST INTO THE PLAINS...WITH
A CLOSED LOW DEVELOPING WITHING THE TROUGH AXIS OVER THE CENTRAL
PLAINS TODAY...MOST LIKELY TRACKING THROUGH CENTRAL KANSAS.

SURFACE OBSERVATIONS REVEAL A COLD FRONT MOVING ACROSS THE STATE
TODAY IN ASSOCIATION WITH THE AFOREMENTIONED UPPER LEVEL TROUGH.

FOR TONIGHT...ENSEMBLES SUGGEST THAT GETTING PRECIPITATION IS PRETTY
MUCH A SURE THING. DIVERGENT Q VECTORS IN UPPER LEVELS INDICATE
VIGOROUS LARGE SCALE LIFT TONIGHT AND THAT GETTING WET IS AN ALMOST
SURE THING...CONSIDERING THE AMPLE MOISTURE AVAILABLE. THIS LIFT
TRANSLATES EAST AFTER MIDNIGHT...AND INDICATES THAT MOST
PRECIPITATION SHOULD SHUT OFF AT THE END OF THE PERIOD. COULD BE
SOME MODERATE MID-LEVEL FRONTOGENESIS ASSOCIATED WITH A DEFORMATION
AREA MAINLY IN THE WEST AND NORTHWEST TONIGHT...WHICH SHOULD ENHANCE
PRECIPITATION AMOUNTS SOMEWHAT...BUT TEMPERATURES ARE IN QUESTION
WHEN IT COMES TO SNOW AMOUNTS. THAT THIS TROUGH SINCE THE BOUNDARY
LAYER IS RELATIVELY WARM...A LOOK AT LEVELS NEAR 875 MB WOULD BE A
BETTER INDICATOR OF CHANGEOVER TO SNOW. THE NAM SUGGESTS THIS WILL
OCCUR IN THE FAR WEST/SOUTHWEST CWA ABOUT 00Z AND TRANSLATE EAST
INTO THE TRI-CITIES AREA BY 06Z OR SO...AND WILL REMAIN BETWEEN 0 AND
MINUS 1 DEGREE CELSIUS FOR THE REMAINDER OF THE NIGHT AS THINGS WIND
DOWN. THE BEST SHOT AT MEASURABLE SNOW APPEARS TO BE CLOSER TO THE
CLOSED LOW IN THE SOUTHWESTERN CWA WHEN TEMPERATURES WILL BE COLD
ENOUGH FOR SNOW. FARTHER EAST...IT APPEARS TEMPERATURES WILL NOT
COOL DOWN ENOUGH FOR MUCH SNOW. COULD GET UP TO A COUPLE OF INCHES
OF SNOW IN THE FAR SOUTHWESTERN CWA...BUT MUCH OF THIS WILL MELT ON
ROAD SURFACES...EXCEPT ON GRASSY SURFACES AND OVERPASSES WHERE IT
MAY CLING A LITTLE BETTER. HIGHEST SNOWFALL TOTALS WILL BE NEAR 2
INCHES IN THE FAR SOUTHWESTERN CWA TOWARD ROOKS COUNTY. AS FAR AS
WIND GOES...PRESSURE RISES AND LOW-LEVEL LAPSE RATES SUGGEST WE WILL
NOT GET WIND ADVISORY CRITERIA...EVEN IN THE FAR SOUTHWEST. WOULD BE
TOUGH TO ACHIEVE ANY SUSTAINED WIND SPEEDS MORE THAN ABOUT 23 KTS IN
THE SOUTHWEST. WHERE THE THIS SUGGESTS A POSSIBLE RAIN/SNOW MIX OR
WHEN IT DOES CHANGE TO SNOW...GETTING ANYTHING ABOVE AN INCH WOULD
BE VERY DIFFICULT. MUCAPES AND MID-LEVEL LAPSE RATES SUGGEST
POSSIBLE SOME ISOLATED THUNDER MAINLY TO THE EAST OF THE CWA TONIGHT
AND DO NOT PLAN TO MENTION THUNDER AT THIS TIME.

FOR TUESDAY...THE ISSUE WILL BE WIND SPEEDS. PRETTY GOOD SURFACE
PRESSURE GRADIENT SETS UP ON THE BACK SIDE OF THE LOW AS IT
TRANSLATES EAST AS WELL AS MIXING UP TO 850 MB WILL BE POSSIBLE
ACCORDING TO THE NAM. THIS WOULD GIVE US WIND GUSTS TO NEAR 30 MPH
FROM THE NORTHWEST. NOT WIND ADVISORY CRITERION...BUT STILL MUCH
WINDIER THAN IT HAS BE FOR SOME TIME.

FOR TUESDAY NIGHT...CONDITIONS SHOULD BE DRY AS A MID-LEVEL
SHORTWAVE RIDGE WILL BE OVERHEAD IN ADVANCE OF THE NEXT WAVE DIVING
SOUTH INTO THE NORTHERN PLAINS.

.LONG TERM...12Z WEDNESDAY THROUGH MONDAY. PRIMARY FORECAST
CONCERN LIES WITH TEMPERATURES.

KEPT FORECAST DRY AT THE START OF THE LONG TERM PERIOD...THOUGH
MODELS IN PRETTY GOOD AGREEMENT SHOWING ANOTHER QUICK MOVING UPPER
LEVEL LOW PRESSURE SYSTEM IN THE REGION.  AT 12Z WEDNESDAY THIS
SYSTEM IS NEAR THE EASTERN ND/SD BOARDER...AND THROUGH THE DAY
SHIFTS TO THE SSE...ENDING UP CENTERED OVER NORTHERN IA BY 00Z
THURSDAY.  ASSOCIATED WITH THIS SYSTEM IS A REINFORCING SFC COLD
FRONT...WHICH IS EXPECTED TO CROSS THROUGH THE CWA EARLY IN THE
MORNING.  MODEL OUTPUT SHOWING AT LEAST SOME LIGHT QPF DEVELOPING
ACROSS PORTIONS OF THE CENTRAL PLAINS...EITHER ACCOMPANYING THE
SYSTEM ITSELF...OR IN RESPONSE TO MORE FAVORABLE POSITIONING OF A
STRONG +110KT UPPER LEVEL JET NOSING IN FROM THE NORTHERN PLAINS.
DID KEEP FORECAST DRY...AS THE CWA SITS IN BETWEEN THOSE MORE
FAVORABLE AREAS...AND FORECAST SOUNDINGS SHOW MUCH DRIER AREA MOVING
IN BEHIND THE SFC FRONT.  EXPECTING THE DAYTIME HOURS ON WEDNESDAY
TO ALSO BE BREEZY...WITH PRESSURE RISES/INCREASED GRADIENT AND
BETTER MIXING ACROSS THE CWA.  THINK THAT WINDS WILL REMAIN BELOW
ADV CRITERIA...WITH SUSTAINED SPEEDS NEAR 20KTS.

THANKSGIVING DAY FORECAST REMAINS DRY...AS THE CWA SITS UNDER THE
INFLUENCE OF NNW UPPER LEVEL FLOW ON THE BACKSIDE OF WEDNESDAYS
SYSTEM.  LOOKING AT THE SFC PATTERN...HIGH PRESSURE SETTLES IN
ACROSS THE REGION DURING THE DAYTIME HOURS...BRINGING GRADUALLY
DIMINISHING WINDS.  AS FAR AS HIGH TEMPERATURES GO FOR
WED/THURS...EVEN WITH A SFC COLD FRONT MOVING THROUGH...NO
SIGNIFICANT CHANGES EXPECTED...WITH HIGHS REMAINING NEAR NORMAL
GENERALLY IN THE 40S AND A FEW READINGS NEAR 50 IN THE SW ON
THURSDAY.

LOOKING TOWARD FRIDAY AND SATURDAY...MODELS IN GOOD AGREEMENT
SHOWING AN AMPLIFYING UPPER LEVEL PATTERN...WITH RIDGING BUILDING IN
OVER THE ROCKIES AS TROUGHS SIT NEAR BOTH COASTS.  EXPECTING WARMEST
DAY TO COME ON FRIDAY...WITH THE RIDGE AXIS SHIFTING OUT OF THE
ROCKIES AND ONTO THE PLAINS.  SFC WINDS BECOME SOUTHERLY AS HIGH
PRESSURE SLIDES OFF TO THE SE AND LOW PRESSURE DEVELOPS ALONG THE
FRONT RANGE.  EXPECTING PLENTY OF SUNSHINE WITH HIGHS IN THE LOWER
TO MID 50S.  ON SATURDAY...THE RIDGE AXIS CONTINUES TO SHIFT EAST
AND STARTS TO BREAK DOWN...WITH UPPER LEVEL FLOW BECOMING
SOUTHWESTERLY AS THE NEXT TROUGH MOVES THROUGH THE ROCKIES.  THIS
BRINGS SLIGHTLY COOLER TEMPS...BUT ONLY INTO THE LOWER 50S.

THINGS BECOME A BIT MORE INTERESTING AS WE GET INTO
SUNDAY/MONDAY...BUT CONFIDENCE ALSO DROPS OFF.  WHILE THE TIMING OF
THIS NEXT SYSTEM IS ACTUALLY NOT TOO BAD BETWEEN MODELS...THERE ARE
DIFFERENCE ON JUST HOW THE PATTERN EVOLVES AS THE TROUGH SHIFTS EAST
AND AN AREA OF LOW PRESSURE DEVELOPS.  BOTH THE GFS AND ECMWF DROP
ENERGY DOWN INTO THE DESERT SW...BUT THE ECMWF DEVELOPS A CLOSED LOW
AND KEEPS THE NORTHERN ENERGY AS AN OPEN TROUGH WHILE THE GFS CLOSES
THE LOW IN THE NORTHERN PLAINS AND THEN DROPS IT SOUTH ACROSS THE
CWA.  OBVIOUSLY THIS CREATES ISSUES WITH WHETHER OR NOT TO MENTION
POPS...AND DECIDED WITH THIS BEING DAY 6/7 TO LEAVE DRY UNTIL THERE
IS BETTER AGREEMENT.

&&

.AVIATION...18Z KGRI TAF. RATHER POOR AVIATION CONDITIONS ARE
FORECAST TO PERSIST FOR THE FIRST 12-18 HOURS OF THE
PERIOD...BEFORE IMPROVING ON TUESDAY MORNING. STARTING OFF THIS
AFTERNOON...AN LIFR/IFR CEILING AND IFR/MVFR VISIBILITY ARE EXPECTED
TO HANG TOUGH FOR SEVERAL MORE HOURS. IT/S WORTH NOTING THAT THIS
IS A MORE PESSIMISTIC CIG/VSBY FORECAST THAN THE PREVIOUS
ONE...AS THE VERY LOWEST LEVELS SHOULD REMAIN QUITE SATURATED.
PRECIPITATION WISE...CHANCES FOR RAIN...AND MAYBE EVENTUALLY A
RAIN/SNOW MIX WILL BE ON THE INCREASE TONIGHT AS A MID LEVEL LOW
PRESSURE SYSTEM ORGANIZES AND MOVES EASTWARD ACROSS KANSAS. ANY
SNOW ACCUMULATIONS AT THE TERMINAL SHOULD BE VERY MINIMAL...LIKELY
UNDER AN INCH. BY LATE TONIGHT...WINDS WILL ALSO BECOME MORE OF AN
ISSUE...AS GUSTS OF 20 TO 30 KTS KICK IN AS THE COLD FRONT SWINGS
BY BEHIND THE DEPARTING LOW. ALTHOUGH THE TIMING COULD EASILY BE
OFF BY A FEW HOURS...HAVE INDICATED A RETURN TO VFR CONDITIONS BY
MID-MORNING TUESDAY. DUE TO THE INHERENT UNCERTAINTIES IN TIMING
THE PRECIPITATION AND CEILING TRENDS IN THIS FORECAST...HAVE TAKEN
THE BEST STAB AT THE MOST LIKELY PREVAILING CONDITIONS...AND
OPTED AGAINST THE INCLUSION OF TEMPO GROUPS.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

000
FXUS63 KOAX 232111
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
311 PM CST MON NOV 23 2009

.SHORT TERM...TONIGHT THROUGH THURSDAY.

WV IMAGERY SHOWING INITIAL SHORTWAVE TROF OF INTEREST WAS SITUATED
OVER THE CNTRL CONUS WITH ANOTHER WAVE UPSTREAM COMING ASHORE OVER
WRN CANADA.

GOOD AGREEMENT THAT MAX OMEGA PHASES WELL WITH MID/UPR QVECT
CONVERGENCE AND DEEP LYR MOISTURE OVER THE CWA TONIGHT AS INITIAL
UPPER LEVEL TROF GRADUALLY TRACKS EAST OVER THE REGION. SFC
REFLECTION WILL STRENGTHEN DURING THIS TIME OVER KANSAS AND DRAG A
COLD FRONT DEEP INTO THE CNTRL/SRN PLAINS. THE QUICK MOVING BOUNDARY
IS PROGGED TO BE PUSHING ACROSS WRN MO/WRN AR/ERN TX BY 12Z TUES. AT
THAT TIME MODELS TAKE THE BRUNT OF DYNAMIC FORCING INTO THE MID MS
VLY...HOWEVER CANNOT RULE OUT LINGERING ACTIVITY THRU TUESDAY AFTN ON
THE BACKSIDE OF THE EXITING SYSTEM. AS FOR PCPN TYPE...AM SEEING
LITTLE PER COBB BUFKIT DATA/CRITICAL THKNS TO SUGGEST ANYTHING MORE
THAN A POTENTIAL FOR RA/SN MIX LATE TONIGHT OVER NORTHEAST NEB. COME
TUESDAY NIGHT...THE NEXT SHORTWAVE TROF OF CONCERN DROPS DOWN THRU
THE DAKOTAS/MN WITH ACCOMPANYING SECONDARY SHOT OF COLD AIR FUNNELING
SWD. AGAIN...VERY STRONG LIFT WITH THIS SECOND WAVE AND RE-ENFORCING
COLD AIRMASS BUT WITH LITTLE MOISTURE TO TAP INTO EXPECT DRY FROPA.
OTHERWISE...THE SERIES SFC COLD FRONT MOVING THRU ARE RELATIVELY WEAK
AND ANTICIPATE RESULT WILL BE ONLY SLIGHTLY BELOW NORMAL AFTN HIGHS
TUES-THURS.

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY.

MODELS ARE IN VERY GOOD AGREEMENT WITH THE LARGE SCALE PATTERN AT
THE START OF THIS PERIOD. THEY SHOW ONE TROUGH ENTERING THE WEST
COAST FROM CNTRL CA NORTHWARD AND ANOTHER OVER THE ERN U.S. AT 00Z
FRIDAY. OUR AREA IS IN NORTHWEST FLOW...WITH A RIDGE OVER THE
ROCKIES AND HIGH PLAINS. THE PATTERN WILL BE PROGRESSIVE...WITH A
BROAD TROUGH OVER THE ROCKIES AND MUCH OF THE PLAINS BY LATE
SATURDAY. TWO DIFFERENT UPPER LEVEL LOWS DEVELOP OVER THE WEEKEND.
ONE WILL DIG OVER THE FOUR CORNERS REGION...WHILE ANOTHER DEVELOPS
OVER THE NORTHERN PLAINS.

IN REGARDS TO THE NORTHERN PLAINS SYSTEM...THE 12Z GFS APPEARS TO
BE A COMPROMISE OF THE 12Z CANADIAN GEM AND THE 12Z ECMWF. THE GEM
DEVELOPS PCPN FROM THE EASTERN DAKOTA AND MINNESOTA SOUTHWARD INTO
EASTERN NEBRASKA SATURDAY. THE 12Z GFS IS MAINLY DRY FOR OUR AREA
UNTIL SUNDAY NIGHT OR MONDAY...WHEN IT SUGGESTS SOME LIGHT SNOW.
THE 00Z AND 12Z ECWWF WERE MAINLY DRY.

EXPECT LOWS DURING THIS PERIOD IN THE 20S TO LOWER 30S AND HIGHS IN
THE 40S TO LOWER 50S.
&&

.AVIATION...
TAF SITES KOFK/KOMA/KLNK

18Z TAFS

SFC LOW PRESSURE OVER WESTERN OKLAHOMA WL CONTINUE TO MOVE NEWD
OVERNIGHT AND TOWARD SERN NEB BY 06Z TONIGHT. PCPN IS EXPECTED TO
MOVE TOWARD TAF SITES LATER THIS EVENING AND MAINLY IN THE FORM OF
RAIN. SOME SNOW COULD MIX IN OVERNIGHT AROUND KOFK...BUT CHANCES ARE
SO SLIM THAT WL NOT MENTION AT THIS POINT. PCPN IS EXPECTED TO
CONTINUE OVERNIGHT AND BEGIN TO TAPER OFF BY MORNING. GUSTY NW WINDS
ARE EXPECTED AS WELL. CIGS SHOULD VARY BETWEEN MVFR AND IFR THRU
MUCH OF THE PD.


&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

$$

DEE/MILLER/BK

000
FXUS63 KLBF 232022
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
222 PM CST MON NOV 23 2009

.DISCUSSION...
THE MODELS HAVE CONGEALED ON A H7 TRACK ALONG OR JUST SOUTH OF THE
KS NEB BORDER. A JET INDUCED DEFORMATION SNOW BAND ACROSS NCNTL NEB
THIS AFTN IS FCST TO WEAKEN THIS EVENING AS A NEW AREA OF DEFORMATION
ASSOCIATED WITH A SECOND JET MAX DEVELOPS ACROSS NCNTL KS AND ERN
NEB. MOST THE SNOW SHOULD BE EAST OF HIGHWAY 183 BY MIDNIGHT WITH
SLOW CLEARING IN THE WEST TOWARD MORNING. BLENDED 12Z SOLNS OF THE
ECMWF...GFS AND NAM PRODUCE AN INCH OR LESS SNOWFALL THIS AFTN AND
TONIGHT FOR TOTALS OF 1 TO 2 INCHES. THE 18Z NAM IS MUCH MORE ROBUST
AND SHOWS 2 TO 6 INCHES OF SNOW THROUGH 9 PM. THIS INDICATES PERIODS
OF 1 INCH PER HOUR SNOW FALL WILL DEVELOP BETWEEN KOGA-KIML-KLBF-KMCK
AND KTIF NECESSITATING A WINTER WEATHER ADVISORY THIS EVENING.
WEATHER CONDITIONS WILL BE EVALUATED BY THE HOUR FOR A POSSIBLE
WINTER WEATHER ADVISORY THIS EVENING.

THE DEVELOPMENT OF A FULL BLOWN TROWAL ZONE AND HEAVY SNOW ACROSS
CNTL PLAINS WILL BE CLOSELY MONITORED AS SUFFICIENT COLD AIR AND
MOISTURE IS IN PLACE ALOFT AND AT THE SFC FOR ACCUMULATING SNOWFALL
TONIGHT. NONE OF THE 12Z MODELS INDICATE A TROWAL EVENT WILL DEVELOP
ACROSS NCNTL NEB BUT THE 18Z NAM INDICATES TROWAL DEVELOPMENT ACROSS
NCNTL KS TONIGHT.

AS THE STORM MOVES INTO THE UPPER MIDWEST TUESDAY A REINFORCING COLD
FRONT IS FCST BY ALL MODELS TO MOVE THROUGH NEBRASKA TUESDAY NIGHT. A
FEW SNOW SHOWERS COULD DEVELOP ACROSS NWRN NEB ASSOCIATED WITH MID
LEVEL MOISTURE CONVERGENCE AND COLD AIR UNDERCUTTING THE
MIDLEVELS. CANADIAN HIGH PRESSURE WILL DROP SOUTH THROUGH THE
MISSOURI BASIN THURSDAY.

THE MODELS THEN FCST LOW PRESSURE TO DEVELOP ACROSS THE WRN HIGH
PLAINS THURSDAY WITH SOUTHERLY RETURN FLOW DEVELOPING. PRESUMABLY...
WEST AND SOUTHWEST COMPONENTS TO THE SOUTHERLY 850 MB WINDS WILL BE
SUFFICIENT TO PUSH A WARM FRONT EAST THROUGH MOST OR ALL OF THE FCST
AREA LATE THURSDAY WITH TEMPERATURES RISING WELL INTO THE 50S
FRIDAY.

A STRONG HYBRID...PACIFIC CANADIAN COLD FRONT AND HIGH PRESSURE
SYSTEM IS FCST TO MOVE THROUGH SATURDAY WITH TEMPERATURES FALL INTO
THE 30S AND 40S SATURDAY THROUGH MONDAY. ATTM IT APPEARS THE FRONT
COULD BE CAPABLE OF LITTLE MORE THAN SNOW SHOWERS BUT POWERFUL
DYNAMICS AND SUBTROPICAL MOISTURE MAY BE NEARBY SO THE NEXT
REASONABLE DISTURBANCE COULD APPEAR OVER THE WEEKEND.

&&

.AVIATION...
CEILINGS AND VISIBILITIES WILL FLUCTUATE THIS AFTERNOON INTO THE
EVENING BEFORE LIFTING AFTER 2406Z TONIGHT. SURFACE OBSERVATIONS
INDICATED MVFR TO IFR CONDITIONS CONTINUE TO EXPAND WEST. THE
IMPACTS TO TERMINAL KLBF WILL BE GREATEST AS INCREASING DYNAMICS
ASSOCIATED WITH THE UPPER LOW TO MOVE SOUTHEAST THROUGH THE NORTHERN
ROCKIES TO OVER NORTHWEST KANSAS THIS EVENING WILL ENHANCE LIFT
ACROSS SOUTHWEST NEBRASKA UNTIL NEAR MIDNIGHT. THE SURFACE FRONT IS
WELL EAST WITH NORTHWEST SURFACE WINDS THROUGHOUT WESTERN NEBRASKA.
THIS EVENING ORGANIZED LIFT SHIFTS SOUTH WITH SNOW TAPERING OFF AND
ENDING NEAR MIDNIGHT AT KLBF. THE EVENTUAL TRACK OF THE STORM MAY
STILL DEVIATE WITH MVFR CONDITIONS UNTIL MIDNIGHT FOR KLBF THEN
RAISED CEILINGS. THIS SCENARIO WILL BE MONITORED THROUGH THE EVENING
WITH ANY SLOWING OF THE SYSTEM PUSHING EAST OVERNIGHT TO LIMIT
CEILINGS LIFTING. THE COMBINATION OF SNOW AND RAIN WILL CONTINUE TO
IMPACT BOTH TERMINALS THROUGH THE AFTERNOON WITH LOCALLY LIFR
CONDITIONS POSSIBLE INTO THE EVENING. AFTER MIDNIGHT MODELS AGREE
WITH SYSTEM PUSHING EAST FOR VISUAL FLIGHT RULES OVERNIGHT THROUGH
18Z TUESDAY.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

CDC/TLK

000
FXUS63 KGID 231910
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
110 PM CST MON NOV 23 2009

.AVIATION...18Z KGRI TAF. RATHER POOR AVIATION CONDITIONS ARE
FORECAST TO PERSIST FOR THE FIRST 12-18 HOURS OF THE
PERIOD...BEFORE IMPROVING ON TUESDAY MORNING. STARTING OFF THIS
AFTERNOON...AN LIFR/IFR CEILING AND IFR/MVFR VISIBILITY ARE EXPECTED
TO HANG TOUGH FOR SEVERAL MORE HOURS. IT/S WORTH NOTING THAT THIS
IS A MORE PESSIMISTIC CIG/VSBY FORECAST THAN THE PREVIOUS
ONE...AS THE VERY LOWEST LEVELS SHOULD REMAIN QUITE SATURATED.
PRECIPITATION WISE...CHANCES FOR RAIN...AND MAYBE EVENTUALLY A
RAIN/SNOW MIX WILL BE ON THE INCREASE TONIGHT AS A MID LEVEL LOW
PRESSURE SYSTEM ORGANIZES AND MOVES EASTWARD ACROSS KANSAS. ANY
SNOW ACCUMULATIONS AT THE TERMINAL SHOULD BE VERY MINIMAL...LIKELY
UNDER AN INCH. BY LATE TONIGHT...WINDS WILL ALSO BECOME MORE OF AN
ISSUE...AS GUSTS OF 20 TO 30 KTS KICK IN AS THE COLD FRONT SWINGS
BY BEHIND THE DEPARTING LOW. ALTHOUGH THE TIMING COULD EASILY BE
OFF BY A FEW HOURS...HAVE INDICATED A RETURN TO VFR CONDITIONS BY
MID-MORNING TUESDAY. DUE TO THE INHERENT UNCERTAINTIES IN TIMING
THE PRECIPITATION AND CEILING TRENDS IN THIS FORECAST...HAVE TAKEN
THE BEST STAB AT THE MOST LIKELY PREVAILING CONDITIONS...AND
OPTED AGAINST THE INCLUSION OF TEMPO GROUPS.

&&

.PREV DISCUSSION... /ISSUED 1209 PM CST MON NOV 23 2009/

DISCUSSION...UPDATED THE FORECAST FOR THE END OF DENSE FOG IN THE
MORNING.

PREV DISCUSSION... /ISSUED 1024 AM CST MON NOV 23 2009/

DISCUSSION...UPDATED THE FORECAST TO INCLUDE DRIZZLE ALONG WITH
THE FOG. WE ACTUALLY MEASURED LOCALLY FROM THE DRIZZLE THIS
MORNING.

PREV DISCUSSION... /ISSUED 446 AM CST MON NOV 23 2009/

DISCUSSION...MAIN CONCERNS ARE DENSE FOG THIS MORNING...AND THEN
PRECIPITATION TYPE AND AMOUNTS TONIGHT.

UPPER TROUGH WAS MAKING ITS WAY ACROSS THE NORTHERN/CENTRAL ROCKIES
OVERNIGHT PER WATER VAPOR IMAGERY. UPPER AIR OBS FROM LAST EVENING
AND RUC ANALYSIS DATA SHOW A 110 KT UPPER JET ON THE BACKSIDE OF THE
TROUGH THAT WILL CONTINUE TO DIG IT TO THE SOUTHEAST
TODAY...EVENTUALLY DEVELOPING A CLOSED CIRCULATION OVER NORTHWEST
KS/FAR SOUTHWEST NE BY THIS EVENING. SURFACE LOW WAS DEEPENING OVER
SOUTHEAST CO/NORTHEAST NM AHEAD OF THE UPPER SYSTEM...WITH SURFACE
COLD FRONT EXTENDING FROM THE WESTERN NE PANHANDLE SOUTHWEST THROUGH
NORTH CENTRAL AND WESTERN CO. WEAK FLOW FIELD WAS IN PLACE AHEAD OF
THESE FEATURES ACROSS THE CENTRAL PLAINS...COMBINING WITH MOIST LOW
LEVELS TO PRODUCE WIDESPREAD DENSE FOG ACROSS THE CWA OVERNIGHT.
REGIONAL RADARS HAVE BEEN SHOWING SOME WEAK ECHOES OVER WESTERN
NE...BUT SURFACE OBS INDICATING THIS LIGHT PRECIP IS STRUGGLING TO
REACH THE SURFACE THUS FAR.

WILL CONTINUE WITH THE DENSE FOG ADVISORY FOR THE ENTIRE CWA AS
VSBYS AT ALL BUT ONE AUTOMATED OBSERVING SITE IN THE CWA ARE
CURRENTLY AT 1/2SM OR LESS. MOS GUIDANCE AND MODEL LOW-LEVEL RH
FIELDS SHOW THIS WILL CONTINUE INTO THE MID TO LATE MORNING...SO
EXPIRATION TIME OF 17Z STILL LOOKS REASONABLE. ONCE THE FOG LIFTS
LATE THIS MORNING...ATTENTION TURNS TOWARD PRECIPITATION CHANCES
WITH UPPER TROUGH AND ATTENDANT COLD FRONT THAT WILL PUSH THROUGH
THE AREA FROM WEST TO EAST TODAY. THE MORNING LOOKS MAINLY
DRY...ALTHOUGH SOME RAIN MAY BEGIN TO SNEAK INTO THE FAR WEST TOWARD
THE NOON HOUR. PRECIP CHANCES THEN INCREASE FROM WEST TO EAST THIS
AFTERNOON AS FORCING INCREASES AHEAD OF UPPER LOW CLOSING OFF OVER
NORTHWEST KS/FAR SOUTHWEST NE BY 00Z TUES. STRONG Q-VECTOR
CONVERGENCE ALONG WITH FRONTOGENETIC FORCING FROM PACIFIC COLD FRONT
SUPPORT PRETTY GOOD RAIN CHANCES THIS AFTERNOON AND HAVE INCREASED
POPS...KEEPING THE HIGHEST VALUES IN THE WEST. THERMAL PROFILES
REMAIN WARM ENOUGH THROUGH THE AFTERNOON TO KEEP PRECIP AS RAIN.

THE MAIN CHALLENGE WITH THIS SYSTEM REMAINS THE CHANGEOVER FROM RAIN
TO SNOW TONIGHT AND RESULTANT SNOWFALL AMOUNTS. SIGNIFICANT COLD
AIR IS LACKING WITH THIS SYSTEM OF PACIFIC ORIGIN...AS CONFIRMED
BY H85 00Z OBS FROM LAST EVENING. HOWEVER THERE DOES APPEAR TO BE
ENOUGH COLD AIR TO SUPPORT A MIX WITH AND EVENTUAL CHANGEOVER TO
SNOW FROM WEST TO EAST THIS EVENING/OVERNIGHT...AND SOME DYNAMIC
COOLING WILL SUPPLEMENT THIS SOMEWHAT AS WELL. NEAR SURFACE TEMPS
ALSO REMAIN FAIRLY WARM HOWEVER...WHICH WILL HAMPER SNOWFALL
ACCUMULATIONS. SURFACE WETBULBS ARE ONLY FORECAST TO FALL INTO
LOWER 30S IN THE WESTERN CWA TONIGHT...WHILE STAYING IN THE MID TO
UPPER 30S IN THE EAST. HENCE EVEN THOUGH PROFILES ALOFT WILL
SUPPORT A CHANGEOVER TO SNOW...DETERMINING HOW MUCH OF THE SNOW WILL
ACCUMULATE REMAINS A CHALLENGE. BASED ON THE RELATIVELY WARM NEAR
SURFACE TEMPS AND THE FACT THAT THE COLDER AIR LAGS THE STRONGER
MID-LEVEL FORCING AND RESULTANT HIGHER QPF...THINK THAT
ACCUMULATIONS WILL REMAIN FAIRLY LIGHT. MUCH OF THE PRECIP ACROSS
THE CENTRAL AND ESPECIALLY EASTERN CWA WILL LIKELY FALL AS RAIN OR
A RAIN/SNOW MIX. HAVE KEPT THE HIGHEST ACCUMULATIONS IN THE
NORTHWEST CWA...WHERE 1-2 INCHES ARE POSSIBLE NORTHWEST OF A
FULLERTON/GRAND ISLAND/PHILLIPSBURG LINE IN THE DEFORMATION BAND
PRECIP...WITH NEAR AN INCH POSSIBLE ALONG THIS SAME
LINE...TAPERING OFF TO LITTLE TO NOTHING IN THE SOUTHEAST.
NORTHWEST WINDS WILL ALSO PICK UP TONIGHT ON THE BACKSIDE OF THE
SYSTEM...REACHING SPEEDS OF 20-30 MPH WITH GUSTS AROUND 35
MPH...WHICH MAY COMBINE WITH THE PRECIP TO PRODUCE SOME REDUCED
VSBYS.

THE DEFORMATION/WRAPAROUND RAIN/SNOW MAY LINGER IN THE EASTERN
CWA INTO TUESDAY MORNING...BUT THE SYSTEM IS PRETTY QUICK TO PULL
OUT INTO IA/MO...BRINGING AN END TO THE PRECIP BY MIDDAY. ONLY
ANTICIPATE SOME LIGHT SNOW ACCUMULATIONS IF ANY /HALF INCH OR
LESS/ IN THE EAST TUESDAY MORNING. BREEZY NORTHWEST WINDS WILL
KEEP IT ON THE COOL SIDE ON TUESDAY...ALTHOUGH CLOSE TO
SEASONAL...WITH HIGHS IN THE 40S. ANOTHER UPPER WAVE DIVES
SOUTHEAST FROM THE NORTHERN PLAINS THROUGH THE UPPER MIDWEST/MID
MS VALLEY ON WEDNESDAY...SENDING A REINFORCING COLD FRONT THROUGH
THE AREA. NOT EXPECTING ANY PRECIP WITH THIS AS A DRY LOWER 10KFT
OR SO OF THE TROPOSPHERE WILL LIKELY KEEP ANYTHING LIMITED TO
VIRGA...AT BEST A STRAY SPRINKLE OR FLURRY. HOWEVER IT WILL KEEP
TEMPS AROUND 40F NORTHEAST TO THE UPPER 40S SOUTHWEST FOR HIGHS.

DRY CONDITIONS AND SEASONAL TEMPS ARE EXPECTED ON THANKSGIVING UNDER
A NORTHWEST FLOW ALOFT...WITH TEMPERATURES THEN MODERATING LATE WEEK
INTO THE FIRST PART OF THE WEEKEND AS THE WESTERN CONUS RIDGE
PROPAGATES EAST.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

AVIATION...PFANNKUCH
PREV DISCUSSIONS...HEINLEIN/KB

000
FXUS63 KGID 231809 AAB
AFDGID

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
1209 PM CST MON NOV 23 2009

.DISCUSSION...UPDATED THE FORECAST FOR THE END OF DENSE FOG IN THE
MORNING.

&&

.PREV DISCUSSION... /ISSUED 1024 AM CST MON NOV 23 2009/

DISCUSSION...UPDATED THE FORECAST TO INCLUDE DRIZZLE ALONG WITH
THE FOG. WE ACTUALLY MEASURED LOCALLY FROM THE DRIZZLE THIS
MORNING.

PREV DISCUSSION... /ISSUED 535 AM CST MON NOV 23 2009/

AVIATION...12Z TAF. THE MAIN ISSUE WILL BE FOG THIS MORNING...AND
THEN RAIN CHANCES LATER THIS AFTERNOON INTO TONIGHT. OBSERVATIONS
FROM ACROSS SOUTH CENTRAL NEBRASKA THIS MORNING SHOW SEVERAL SPOTS
WITH VISIBILITIES LESS THAN 1/2SM IN FOG. CURRENTLY KGRI IS CLOSER
TO 2SM...BUT THINK THAT THERE IS STILL THE POTENTIAL FOR LOWER
VISIBILITIES OVER THE NEXT FEW HOURS DUE TO NEARLY SATURATED
CONDITIONS IN THE LOWER PARTS OF THE ATMOSPHERE. WILL STILL DROP
VISIBILITIES TO AROUND 1/2SM AT KGRI FOR A FEW HOURS IN A TEMPO
GROUP...BUT GO WITH A PREVAILING VISIBILITY AROUND 2SM. FORECAST
SOUNDINGS SUGGEST THERE WILL BE SLOW IMPROVEMENT AT KGRI THIS
MORNING..AND WILL GET RID OF MOST OF THE VISIBILITY RESTRICTIONS
TOWARD 16Z. THE LOW CLOUDS WILL LIKELY PREVAIL LONGER...THOUGH
CEILINGS SHOULD ALSO GRADUALLY IMPROVE BACK TO MVFR LEVELS THIS
AFTERNOON. A STORM SYSTEM MOVING ACROSS THE REGION WILL THEN BRING
A CHANCE OF RAIN TO KGRI STARTING LATE THIS AFTERNOON...WHICH WILL
CONTINUE INTO TONIGHT. INSTEAD OF CARRYING PROB OR TEMPO GROUPS
FOR THE RAIN...DECIDED TO JUST CARRY RAIN IN A PREVAILING GROUP
LATE THIS AFTERNOON SINCE SEVERAL DIFFERENT FORECAST MODELS SHOW
THE RAIN BEGINNING AROUND THAT TIME. THERE IS ALSO SOME CHANCE
THAT SNOW COULD MIX WITH THE RAIN LATE TONIGHT...AND PUT THAT IN
TOWARDS 08Z. WINDS WILL ALSO BE ON THE INCREASE LATER TONIGHT WITH
GUSTS OF 25 TO 30 KTS POSSIBLE.

PREV DISCUSSION... /ISSUED 446 AM CST MON NOV 23 2009/

DISCUSSION...MAIN CONCERNS ARE DENSE FOG THIS MORNING...AND THEN
PRECIPITATION TYPE AND AMOUNTS TONIGHT.

UPPER TROUGH WAS MAKING ITS WAY ACROSS THE NORTHERN/CENTRAL ROCKIES
OVERNIGHT PER WATER VAPOR IMAGERY. UPPER AIR OBS FROM LAST EVENING
AND RUC ANALYSIS DATA SHOW A 110 KT UPPER JET ON THE BACKSIDE OF THE
TROUGH THAT WILL CONTINUE TO DIG IT TO THE SOUTHEAST
TODAY...EVENTUALLY DEVELOPING A CLOSED CIRCULATION OVER NORTHWEST
KS/FAR SOUTHWEST NE BY THIS EVENING. SURFACE LOW WAS DEEPENING OVER
SOUTHEAST CO/NORTHEAST NM AHEAD OF THE UPPER SYSTEM...WITH SURFACE
COLD FRONT EXTENDING FROM THE WESTERN NE PANHANDLE SOUTHWEST THROUGH
NORTH CENTRAL AND WESTERN CO. WEAK FLOW FIELD WAS IN PLACE AHEAD OF
THESE FEATURES ACROSS THE CENTRAL PLAINS...COMBINING WITH MOIST LOW
LEVELS TO PRODUCE WIDESPREAD DENSE FOG ACROSS THE CWA OVERNIGHT.
REGIONAL RADARS HAVE BEEN SHOWING SOME WEAK ECHOES OVER WESTERN
NE...BUT SURFACE OBS INDICATING THIS LIGHT PRECIP IS STRUGGLING TO
REACH THE SURFACE THUS FAR.

WILL CONTINUE WITH THE DENSE FOG ADVISORY FOR THE ENTIRE CWA AS
VSBYS AT ALL BUT ONE AUTOMATED OBSERVING SITE IN THE CWA ARE
CURRENTLY AT 1/2SM OR LESS. MOS GUIDANCE AND MODEL LOW-LEVEL RH
FIELDS SHOW THIS WILL CONTINUE INTO THE MID TO LATE MORNING...SO
EXPIRATION TIME OF 17Z STILL LOOKS REASONABLE. ONCE THE FOG LIFTS
LATE THIS MORNING...ATTENTION TURNS TOWARD PRECIPITATION CHANCES
WITH UPPER TROUGH AND ATTENDANT COLD FRONT THAT WILL PUSH THROUGH
THE AREA FROM WEST TO EAST TODAY. THE MORNING LOOKS MAINLY
DRY...ALTHOUGH SOME RAIN MAY BEGIN TO SNEAK INTO THE FAR WEST TOWARD
THE NOON HOUR. PRECIP CHANCES THEN INCREASE FROM WEST TO EAST THIS
AFTERNOON AS FORCING INCREASES AHEAD OF UPPER LOW CLOSING OFF OVER
NORTHWEST KS/FAR SOUTHWEST NE BY 00Z TUES. STRONG Q-VECTOR
CONVERGENCE ALONG WITH FRONTOGENETIC FORCING FROM PACIFIC COLD FRONT
SUPPORT PRETTY GOOD RAIN CHANCES THIS AFTERNOON AND HAVE INCREASED
POPS...KEEPING THE HIGHEST VALUES IN THE WEST. THERMAL PROFILES
REMAIN WARM ENOUGH THROUGH THE AFTERNOON TO KEEP PRECIP AS RAIN.

THE MAIN CHALLENGE WITH THIS SYSTEM REMAINS THE CHANGEOVER FROM RAIN
TO SNOW TONIGHT AND RESULTANT SNOWFALL AMOUNTS. SIGNIFICANT COLD
AIR IS LACKING WITH THIS SYSTEM OF PACIFIC ORIGIN...AS CONFIRMED
BY H85 00Z OBS FROM LAST EVENING. HOWEVER THERE DOES APPEAR TO BE
ENOUGH COLD AIR TO SUPPORT A MIX WITH AND EVENTUAL CHANGEOVER TO
SNOW FROM WEST TO EAST THIS EVENING/OVERNIGHT...AND SOME DYNAMIC
COOLING WILL SUPPLEMENT THIS SOMEWHAT AS WELL. NEAR SURFACE TEMPS
ALSO REMAIN FAIRLY WARM HOWEVER...WHICH WILL HAMPER SNOWFALL
ACCUMULATIONS. SURFACE WETBULBS ARE ONLY FORECAST TO FALL INTO
LOWER 30S IN THE WESTERN CWA TONIGHT...WHILE STAYING IN THE MID TO
UPPER 30S IN THE EAST. HENCE EVEN THOUGH PROFILES ALOFT WILL
SUPPORT A CHANGEOVER TO SNOW...DETERMINING HOW MUCH OF THE SNOW WILL
ACCUMULATE REMAINS A CHALLENGE. BASED ON THE RELATIVELY WARM NEAR
SURFACE TEMPS AND THE FACT THAT THE COLDER AIR LAGS THE STRONGER
MID-LEVEL FORCING AND RESULTANT HIGHER QPF...THINK THAT
ACCUMULATIONS WILL REMAIN FAIRLY LIGHT. MUCH OF THE PRECIP ACROSS
THE CENTRAL AND ESPECIALLY EASTERN CWA WILL LIKELY FALL AS RAIN OR
A RAIN/SNOW MIX. HAVE KEPT THE HIGHEST ACCUMULATIONS IN THE
NORTHWEST CWA...WHERE 1-2 INCHES ARE POSSIBLE NORTHWEST OF A
FULLERTON/GRAND ISLAND/PHILLIPSBURG LINE IN THE DEFORMATION BAND
PRECIP...WITH NEAR AN INCH POSSIBLE ALONG THIS SAME
LINE...TAPERING OFF TO LITTLE TO NOTHING IN THE SOUTHEAST.
NORTHWEST WINDS WILL ALSO PICK UP TONIGHT ON THE BACKSIDE OF THE
SYSTEM...REACHING SPEEDS OF 20-30 MPH WITH GUSTS AROUND 35
MPH...WHICH MAY COMBINE WITH THE PRECIP TO PRODUCE SOME REDUCED
VSBYS.

THE DEFORMATION/WRAPAROUND RAIN/SNOW MAY LINGER IN THE EASTERN
CWA INTO TUESDAY MORNING...BUT THE SYSTEM IS PRETTY QUICK TO PULL
OUT INTO IA/MO...BRINGING AN END TO THE PRECIP BY MIDDAY. ONLY
ANTICIPATE SOME LIGHT SNOW ACCUMULATIONS IF ANY /HALF INCH OR
LESS/ IN THE EAST TUESDAY MORNING. BREEZY NORTHWEST WINDS WILL
KEEP IT ON THE COOL SIDE ON TUESDAY...ALTHOUGH CLOSE TO
SEASONAL...WITH HIGHS IN THE 40S. ANOTHER UPPER WAVE DIVES
SOUTHEAST FROM THE NORTHERN PLAINS THROUGH THE UPPER MIDWEST/MID
MS VALLEY ON WEDNESDAY...SENDING A REINFORCING COLD FRONT THROUGH
THE AREA. NOT EXPECTING ANY PRECIP WITH THIS AS A DRY LOWER 10KFT
OR SO OF THE TROPOSPHERE WILL LIKELY KEEP ANYTHING LIMITED TO
VIRGA...AT BEST A STRAY SPRINKLE OR FLURRY. HOWEVER IT WILL KEEP
TEMPS AROUND 40F NORTHEAST TO THE UPPER 40S SOUTHWEST FOR HIGHS.

DRY CONDITIONS AND SEASONAL TEMPS ARE EXPECTED ON THANKSGIVING UNDER
A NORTHWEST FLOW ALOFT...WITH TEMPERATURES THEN MODERATING LATE WEEK
INTO THE FIRST PART OF THE WEEKEND AS THE WESTERN CONUS RIDGE
PROPAGATES EAST.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

HEINLEIN

000
FXUS63 KGID 231624 AAA
AFDGID

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
1024 AM CST MON NOV 23 2009

.DISCUSSION...UPDATED THE FORECAST TO INCLUDE DRIZZLE ALONG WITH
THE FOG. WE ACTUALLY MEASURED LOCALLY FROM THE DRIZZLE THIS
MORNING.

&&

.PREV DISCUSSION... /ISSUED 535 AM CST MON NOV 23 2009/

AVIATION...12Z TAF. THE MAIN ISSUE WILL BE FOG THIS MORNING...AND
THEN RAIN CHANCES LATER THIS AFTERNOON INTO TONIGHT. OBSERVATIONS
FROM ACROSS SOUTH CENTRAL NEBRASKA THIS MORNING SHOW SEVERAL SPOTS
WITH VISIBILITIES LESS THAN 1/2SM IN FOG. CURRENTLY KGRI IS CLOSER
TO 2SM...BUT THINK THAT THERE IS STILL THE POTENTIAL FOR LOWER
VISIBILITIES OVER THE NEXT FEW HOURS DUE TO NEARLY SATURATED
CONDITIONS IN THE LOWER PARTS OF THE ATMOSPHERE. WILL STILL DROP
VISIBILITIES TO AROUND 1/2SM AT KGRI FOR A FEW HOURS IN A TEMPO
GROUP...BUT GO WITH A PREVAILING VISIBILITY AROUND 2SM. FORECAST
SOUNDINGS SUGGEST THERE WILL BE SLOW IMPROVEMENT AT KGRI THIS
MORNING..AND WILL GET RID OF MOST OF THE VISIBILITY RESTRICTIONS
TOWARD 16Z. THE LOW CLOUDS WILL LIKELY PREVAIL LONGER...THOUGH
CEILINGS SHOULD ALSO GRADUALLY IMPROVE BACK TO MVFR LEVELS THIS
AFTERNOON. A STORM SYSTEM MOVING ACROSS THE REGION WILL THEN BRING
A CHANCE OF RAIN TO KGRI STARTING LATE THIS AFTERNOON...WHICH WILL
CONTINUE INTO TONIGHT. INSTEAD OF CARRYING PROB OR TEMPO GROUPS
FOR THE RAIN...DECIDED TO JUST CARRY RAIN IN A PREVAILING GROUP
LATE THIS AFTERNOON SINCE SEVERAL DIFFERENT FORECAST MODELS SHOW
THE RAIN BEGINNING AROUND THAT TIME. THERE IS ALSO SOME CHANCE
THAT SNOW COULD MIX WITH THE RAIN LATE TONIGHT...AND PUT THAT IN
TOWARDS 08Z. WINDS WILL ALSO BE ON THE INCREASE LATER TONIGHT WITH
GUSTS OF 25 TO 30 KTS POSSIBLE.

PREV DISCUSSION... /ISSUED 446 AM CST MON NOV 23 2009/

DISCUSSION...MAIN CONCERNS ARE DENSE FOG THIS MORNING...AND THEN
PRECIPITATION TYPE AND AMOUNTS TONIGHT.

UPPER TROUGH WAS MAKING ITS WAY ACROSS THE NORTHERN/CENTRAL ROCKIES
OVERNIGHT PER WATER VAPOR IMAGERY. UPPER AIR OBS FROM LAST EVENING
AND RUC ANALYSIS DATA SHOW A 110 KT UPPER JET ON THE BACKSIDE OF THE
TROUGH THAT WILL CONTINUE TO DIG IT TO THE SOUTHEAST
TODAY...EVENTUALLY DEVELOPING A CLOSED CIRCULATION OVER NORTHWEST
KS/FAR SOUTHWEST NE BY THIS EVENING. SURFACE LOW WAS DEEPENING OVER
SOUTHEAST CO/NORTHEAST NM AHEAD OF THE UPPER SYSTEM...WITH SURFACE
COLD FRONT EXTENDING FROM THE WESTERN NE PANHANDLE SOUTHWEST THROUGH
NORTH CENTRAL AND WESTERN CO. WEAK FLOW FIELD WAS IN PLACE AHEAD OF
THESE FEATURES ACROSS THE CENTRAL PLAINS...COMBINING WITH MOIST LOW
LEVELS TO PRODUCE WIDESPREAD DENSE FOG ACROSS THE CWA OVERNIGHT.
REGIONAL RADARS HAVE BEEN SHOWING SOME WEAK ECHOES OVER WESTERN
NE...BUT SURFACE OBS INDICATING THIS LIGHT PRECIP IS STRUGGLING TO
REACH THE SURFACE THUS FAR.

WILL CONTINUE WITH THE DENSE FOG ADVISORY FOR THE ENTIRE CWA AS
VSBYS AT ALL BUT ONE AUTOMATED OBSERVING SITE IN THE CWA ARE
CURRENTLY AT 1/2SM OR LESS. MOS GUIDANCE AND MODEL LOW-LEVEL RH
FIELDS SHOW THIS WILL CONTINUE INTO THE MID TO LATE MORNING...SO
EXPIRATION TIME OF 17Z STILL LOOKS REASONABLE. ONCE THE FOG LIFTS
LATE THIS MORNING...ATTENTION TURNS TOWARD PRECIPITATION CHANCES
WITH UPPER TROUGH AND ATTENDANT COLD FRONT THAT WILL PUSH THROUGH
THE AREA FROM WEST TO EAST TODAY. THE MORNING LOOKS MAINLY
DRY...ALTHOUGH SOME RAIN MAY BEGIN TO SNEAK INTO THE FAR WEST TOWARD
THE NOON HOUR. PRECIP CHANCES THEN INCREASE FROM WEST TO EAST THIS
AFTERNOON AS FORCING INCREASES AHEAD OF UPPER LOW CLOSING OFF OVER
NORTHWEST KS/FAR SOUTHWEST NE BY 00Z TUES. STRONG Q-VECTOR
CONVERGENCE ALONG WITH FRONTOGENETIC FORCING FROM PACIFIC COLD FRONT
SUPPORT PRETTY GOOD RAIN CHANCES THIS AFTERNOON AND HAVE INCREASED
POPS...KEEPING THE HIGHEST VALUES IN THE WEST. THERMAL PROFILES
REMAIN WARM ENOUGH THROUGH THE AFTERNOON TO KEEP PRECIP AS RAIN.

THE MAIN CHALLENGE WITH THIS SYSTEM REMAINS THE CHANGEOVER FROM RAIN
TO SNOW TONIGHT AND RESULTANT SNOWFALL AMOUNTS. SIGNIFICANT COLD
AIR IS LACKING WITH THIS SYSTEM OF PACIFIC ORIGIN...AS CONFIRMED
BY H85 00Z OBS FROM LAST EVENING. HOWEVER THERE DOES APPEAR TO BE
ENOUGH COLD AIR TO SUPPORT A MIX WITH AND EVENTUAL CHANGEOVER TO
SNOW FROM WEST TO EAST THIS EVENING/OVERNIGHT...AND SOME DYNAMIC
COOLING WILL SUPPLEMENT THIS SOMEWHAT AS WELL. NEAR SURFACE TEMPS
ALSO REMAIN FAIRLY WARM HOWEVER...WHICH WILL HAMPER SNOWFALL
ACCUMULATIONS. SURFACE WETBULBS ARE ONLY FORECAST TO FALL INTO
LOWER 30S IN THE WESTERN CWA TONIGHT...WHILE STAYING IN THE MID TO
UPPER 30S IN THE EAST. HENCE EVEN THOUGH PROFILES ALOFT WILL
SUPPORT A CHANGEOVER TO SNOW...DETERMINING HOW MUCH OF THE SNOW WILL
ACCUMULATE REMAINS A CHALLENGE. BASED ON THE RELATIVELY WARM NEAR
SURFACE TEMPS AND THE FACT THAT THE COLDER AIR LAGS THE STRONGER
MID-LEVEL FORCING AND RESULTANT HIGHER QPF...THINK THAT
ACCUMULATIONS WILL REMAIN FAIRLY LIGHT. MUCH OF THE PRECIP ACROSS
THE CENTRAL AND ESPECIALLY EASTERN CWA WILL LIKELY FALL AS RAIN OR
A RAIN/SNOW MIX. HAVE KEPT THE HIGHEST ACCUMULATIONS IN THE
NORTHWEST CWA...WHERE 1-2 INCHES ARE POSSIBLE NORTHWEST OF A
FULLERTON/GRAND ISLAND/PHILLIPSBURG LINE IN THE DEFORMATION BAND
PRECIP...WITH NEAR AN INCH POSSIBLE ALONG THIS SAME
LINE...TAPERING OFF TO LITTLE TO NOTHING IN THE SOUTHEAST.
NORTHWEST WINDS WILL ALSO PICK UP TONIGHT ON THE BACKSIDE OF THE
SYSTEM...REACHING SPEEDS OF 20-30 MPH WITH GUSTS AROUND 35
MPH...WHICH MAY COMBINE WITH THE PRECIP TO PRODUCE SOME REDUCED
VSBYS.

THE DEFORMATION/WRAPAROUND RAIN/SNOW MAY LINGER IN THE EASTERN
CWA INTO TUESDAY MORNING...BUT THE SYSTEM IS PRETTY QUICK TO PULL
OUT INTO IA/MO...BRINGING AN END TO THE PRECIP BY MIDDAY. ONLY
ANTICIPATE SOME LIGHT SNOW ACCUMULATIONS IF ANY /HALF INCH OR
LESS/ IN THE EAST TUESDAY MORNING. BREEZY NORTHWEST WINDS WILL
KEEP IT ON THE COOL SIDE ON TUESDAY...ALTHOUGH CLOSE TO
SEASONAL...WITH HIGHS IN THE 40S. ANOTHER UPPER WAVE DIVES
SOUTHEAST FROM THE NORTHERN PLAINS THROUGH THE UPPER MIDWEST/MID
MS VALLEY ON WEDNESDAY...SENDING A REINFORCING COLD FRONT THROUGH
THE AREA. NOT EXPECTING ANY PRECIP WITH THIS AS A DRY LOWER 10KFT
OR SO OF THE TROPOSPHERE WILL LIKELY KEEP ANYTHING LIMITED TO
VIRGA...AT BEST A STRAY SPRINKLE OR FLURRY. HOWEVER IT WILL KEEP
TEMPS AROUND 40F NORTHEAST TO THE UPPER 40S SOUTHWEST FOR HIGHS.

DRY CONDITIONS AND SEASONAL TEMPS ARE EXPECTED ON THANKSGIVING UNDER
A NORTHWEST FLOW ALOFT...WITH TEMPERATURES THEN MODERATING LATE WEEK
INTO THE FIRST PART OF THE WEEKEND AS THE WESTERN CONUS RIDGE
PROPAGATES EAST.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR NEZ039>041-
     046>049-060>064-072>077-082>087.

KS...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ005>007-
     017>019.

&&

$$

HEINLEIN

000
FXUS63 KGID 231135
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
535 AM CST MON NOV 23 2009

.AVIATION...12Z TAF. THE MAIN ISSUE WILL BE FOG THIS MORNING...AND
THEN RAIN CHANCES LATER THIS AFTERNOON INTO TONIGHT. OBSERVATIONS
FROM ACROSS SOUTH CENTRAL NEBRASKA THIS MORNING SHOW SEVERAL SPOTS
WITH VISIBILITIES LESS THAN 1/2SM IN FOG. CURRENTLY KGRI IS CLOSER
TO 2SM...BUT THINK THAT THERE IS STILL THE POTENTIAL FOR LOWER
VISIBILITIES OVER THE NEXT FEW HOURS DUE TO NEARLY SATURATED
CONDITIONS IN THE LOWER PARTS OF THE ATMOSPHERE. WILL STILL DROP
VISIBILITIES TO AROUND 1/2SM AT KGRI FOR A FEW HOURS IN A TEMPO
GROUP...BUT GO WITH A PREVAILING VISIBILITY AROUND 2SM. FORECAST
SOUNDINGS SUGGEST THERE WILL BE SLOW IMPROVEMENT AT KGRI THIS
MORNING..AND WILL GET RID OF MOST OF THE VISIBILITY RESTRICTIONS
TOWARD 16Z. THE LOW CLOUDS WILL LIKELY PREVAIL LONGER...THOUGH
CEILINGS SHOULD ALSO GRADUALLY IMPROVE BACK TO MVFR LEVELS THIS
AFTERNOON. A STORM SYSTEM MOVING ACROSS THE REGION WILL THEN BRING
A CHANCE OF RAIN TO KGRI STARTING LATE THIS AFTERNOON...WHICH WILL
CONTINUE INTO TONIGHT. INSTEAD OF CARRYING PROB OR TEMPO GROUPS
FOR THE RAIN...DECIDED TO JUST CARRY RAIN IN A PREVAILING GROUP
LATE THIS AFTERNOON SINCE SEVERAL DIFFERENT FORECAST MODELS SHOW
THE RAIN BEGINNING AROUND THAT TIME. THERE IS ALSO SOME CHANCE
THAT SNOW COULD MIX WITH THE RAIN LATE TONIGHT...AND PUT THAT IN
TOWARDS 08Z. WINDS WILL ALSO BE ON THE INCREASE LATER TONIGHT WITH
GUSTS OF 25 TO 30 KTS POSSIBLE.

&&

.PREV DISCUSSION... /ISSUED 446 AM CST MON NOV 23 2009/

DISCUSSION...MAIN CONCERNS ARE DENSE FOG THIS MORNING...AND THEN
PRECIPITATION TYPE AND AMOUNTS TONIGHT.

UPPER TROUGH WAS MAKING ITS WAY ACROSS THE NORTHERN/CENTRAL ROCKIES
OVERNIGHT PER WATER VAPOR IMAGERY. UPPER AIR OBS FROM LAST EVENING
AND RUC ANALYSIS DATA SHOW A 110 KT UPPER JET ON THE BACKSIDE OF THE
TROUGH THAT WILL CONTINUE TO DIG IT TO THE SOUTHEAST
TODAY...EVENTUALLY DEVELOPING A CLOSED CIRCULATION OVER NORTHWEST
KS/FAR SOUTHWEST NE BY THIS EVENING. SURFACE LOW WAS DEEPENING OVER
SOUTHEAST CO/NORTHEAST NM AHEAD OF THE UPPER SYSTEM...WITH SURFACE
COLD FRONT EXTENDING FROM THE WESTERN NE PANHANDLE SOUTHWEST THROUGH
NORTH CENTRAL AND WESTERN CO. WEAK FLOW FIELD WAS IN PLACE AHEAD OF
THESE FEATURES ACROSS THE CENTRAL PLAINS...COMBINING WITH MOIST LOW
LEVELS TO PRODUCE WIDESPREAD DENSE FOG ACROSS THE CWA OVERNIGHT.
REGIONAL RADARS HAVE BEEN SHOWING SOME WEAK ECHOES OVER WESTERN
NE...BUT SURFACE OBS INDICATING THIS LIGHT PRECIP IS STRUGGLING TO
REACH THE SURFACE THUS FAR.

WILL CONTINUE WITH THE DENSE FOG ADVISORY FOR THE ENTIRE CWA AS
VSBYS AT ALL BUT ONE AUTOMATED OBSERVING SITE IN THE CWA ARE
CURRENTLY AT 1/2SM OR LESS. MOS GUIDANCE AND MODEL LOW-LEVEL RH
FIELDS SHOW THIS WILL CONTINUE INTO THE MID TO LATE MORNING...SO
EXPIRATION TIME OF 17Z STILL LOOKS REASONABLE. ONCE THE FOG LIFTS
LATE THIS MORNING...ATTENTION TURNS TOWARD PRECIPITATION CHANCES
WITH UPPER TROUGH AND ATTENDANT COLD FRONT THAT WILL PUSH THROUGH
THE AREA FROM WEST TO EAST TODAY. THE MORNING LOOKS MAINLY
DRY...ALTHOUGH SOME RAIN MAY BEGIN TO SNEAK INTO THE FAR WEST TOWARD
THE NOON HOUR. PRECIP CHANCES THEN INCREASE FROM WEST TO EAST THIS
AFTERNOON AS FORCING INCREASES AHEAD OF UPPER LOW CLOSING OFF OVER
NORTHWEST KS/FAR SOUTHWEST NE BY 00Z TUES. STRONG Q-VECTOR
CONVERGENCE ALONG WITH FRONTOGENETIC FORCING FROM PACIFIC COLD FRONT
SUPPORT PRETTY GOOD RAIN CHANCES THIS AFTERNOON AND HAVE INCREASED
POPS...KEEPING THE HIGHEST VALUES IN THE WEST. THERMAL PROFILES
REMAIN WARM ENOUGH THROUGH THE AFTERNOON TO KEEP PRECIP AS RAIN.

THE MAIN CHALLENGE WITH THIS SYSTEM REMAINS THE CHANGEOVER FROM RAIN
TO SNOW TONIGHT AND RESULTANT SNOWFALL AMOUNTS. SIGNIFICANT COLD
AIR IS LACKING WITH THIS SYSTEM OF PACIFIC ORIGIN...AS CONFIRMED
BY H85 00Z OBS FROM LAST EVENING. HOWEVER THERE DOES APPEAR TO BE
ENOUGH COLD AIR TO SUPPORT A MIX WITH AND EVENTUAL CHANGEOVER TO
SNOW FROM WEST TO EAST THIS EVENING/OVERNIGHT...AND SOME DYNAMIC
COOLING WILL SUPPLEMENT THIS SOMEWHAT AS WELL. NEAR SURFACE TEMPS
ALSO REMAIN FAIRLY WARM HOWEVER...WHICH WILL HAMPER SNOWFALL
ACCUMULATIONS. SURFACE WETBULBS ARE ONLY FORECAST TO FALL INTO
LOWER 30S IN THE WESTERN CWA TONIGHT...WHILE STAYING IN THE MID TO
UPPER 30S IN THE EAST. HENCE EVEN THOUGH PROFILES ALOFT WILL
SUPPORT A CHANGEOVER TO SNOW...DETERMINING HOW MUCH OF THE SNOW WILL
ACCUMULATE REMAINS A CHALLENGE. BASED ON THE RELATIVELY WARM NEAR
SURFACE TEMPS AND THE FACT THAT THE COLDER AIR LAGS THE STRONGER
MID-LEVEL FORCING AND RESULTANT HIGHER QPF...THINK THAT
ACCUMULATIONS WILL REMAIN FAIRLY LIGHT. MUCH OF THE PRECIP ACROSS
THE CENTRAL AND ESPECIALLY EASTERN CWA WILL LIKELY FALL AS RAIN OR
A RAIN/SNOW MIX. HAVE KEPT THE HIGHEST ACCUMULATIONS IN THE
NORTHWEST CWA...WHERE 1-2 INCHES ARE POSSIBLE NORTHWEST OF A
FULLERTON/GRAND ISLAND/PHILLIPSBURG LINE IN THE DEFORMATION BAND
PRECIP...WITH NEAR AN INCH POSSIBLE ALONG THIS SAME
LINE...TAPERING OFF TO LITTLE TO NOTHING IN THE SOUTHEAST.
NORTHWEST WINDS WILL ALSO PICK UP TONIGHT ON THE BACKSIDE OF THE
SYSTEM...REACHING SPEEDS OF 20-30 MPH WITH GUSTS AROUND 35
MPH...WHICH MAY COMBINE WITH THE PRECIP TO PRODUCE SOME REDUCED
VSBYS.

THE DEFORMATION/WRAPAROUND RAIN/SNOW MAY LINGER IN THE EASTERN
CWA INTO TUESDAY MORNING...BUT THE SYSTEM IS PRETTY QUICK TO PULL
OUT INTO IA/MO...BRINGING AN END TO THE PRECIP BY MIDDAY. ONLY
ANTICIPATE SOME LIGHT SNOW ACCUMULATIONS IF ANY /HALF INCH OR
LESS/ IN THE EAST TUESDAY MORNING. BREEZY NORTHWEST WINDS WILL
KEEP IT ON THE COOL SIDE ON TUESDAY...ALTHOUGH CLOSE TO
SEASONAL...WITH HIGHS IN THE 40S. ANOTHER UPPER WAVE DIVES
SOUTHEAST FROM THE NORTHERN PLAINS THROUGH THE UPPER MIDWEST/MID
MS VALLEY ON WEDNESDAY...SENDING A REINFORCING COLD FRONT THROUGH
THE AREA. NOT EXPECTING ANY PRECIP WITH THIS AS A DRY LOWER 10KFT
OR SO OF THE TROPOSPHERE WILL LIKELY KEEP ANYTHING LIMITED TO
VIRGA...AT BEST A STRAY SPRINKLE OR FLURRY. HOWEVER IT WILL KEEP
TEMPS AROUND 40F NORTHEAST TO THE UPPER 40S SOUTHWEST FOR HIGHS.

DRY CONDITIONS AND SEASONAL TEMPS ARE EXPECTED ON THANKSGIVING UNDER
A NORTHWEST FLOW ALOFT...WITH TEMPERATURES THEN MODERATING LATE WEEK
INTO THE FIRST PART OF THE WEEKEND AS THE WESTERN CONUS RIDGE
PROPAGATES EAST.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR NEZ039>041-
     046>049-060>064-072>077-082>087.

KS...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ005>007-
     017>019.

&&

$$

000
FXUS63 KGID 231046
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
446 AM CST MON NOV 23 2009

.DISCUSSION...MAIN CONCERNS ARE DENSE FOG THIS MORNING...AND THEN
PRECIPITATION TYPE AND AMOUNTS TONIGHT.

UPPER TROUGH WAS MAKING ITS WAY ACROSS THE NORTHERN/CENTRAL ROCKIES
OVERNIGHT PER WATER VAPOR IMAGERY. UPPER AIR OBS FROM LAST EVENING
AND RUC ANALYSIS DATA SHOW A 110 KT UPPER JET ON THE BACKSIDE OF THE
TROUGH THAT WILL CONTINUE TO DIG IT TO THE SOUTHEAST
TODAY...EVENTUALLY DEVELOPING A CLOSED CIRCULATION OVER NORTHWEST
KS/FAR SOUTHWEST NE BY THIS EVENING. SURFACE LOW WAS DEEPENING OVER
SOUTHEAST CO/NORTHEAST NM AHEAD OF THE UPPER SYSTEM...WITH SURFACE
COLD FRONT EXTENDING FROM THE WESTERN NE PANHANDLE SOUTHWEST THROUGH
NORTH CENTRAL AND WESTERN CO. WEAK FLOW FIELD WAS IN PLACE AHEAD OF
THESE FEATURES ACROSS THE CENTRAL PLAINS...COMBINING WITH MOIST LOW
LEVELS TO PRODUCE WIDESPREAD DENSE FOG ACROSS THE CWA OVERNIGHT.
REGIONAL RADARS HAVE BEEN SHOWING SOME WEAK ECHOES OVER WESTERN
NE...BUT SURFACE OBS INDICATING THIS LIGHT PRECIP IS STRUGGLING TO
REACH THE SURFACE THUS FAR.

WILL CONTINUE WITH THE DENSE FOG ADVISORY FOR THE ENTIRE CWA AS
VSBYS AT ALL BUT ONE AUTOMATED OBSERVING SITE IN THE CWA ARE
CURRENTLY AT 1/2SM OR LESS. MOS GUIDANCE AND MODEL LOW-LEVEL RH
FIELDS SHOW THIS WILL CONTINUE INTO THE MID TO LATE MORNING...SO
EXPIRATION TIME OF 17Z STILL LOOKS REASONABLE. ONCE THE FOG LIFTS
LATE THIS MORNING...ATTENTION TURNS TOWARD PRECIPITATION CHANCES
WITH UPPER TROUGH AND ATTENDANT COLD FRONT THAT WILL PUSH THROUGH
THE AREA FROM WEST TO EAST TODAY. THE MORNING LOOKS MAINLY
DRY...ALTHOUGH SOME RAIN MAY BEGIN TO SNEAK INTO THE FAR WEST TOWARD
THE NOON HOUR. PRECIP CHANCES THEN INCREASE FROM WEST TO EAST THIS
AFTERNOON AS FORCING INCREASES AHEAD OF UPPER LOW CLOSING OFF OVER
NORTHWEST KS/FAR SOUTHWEST NE BY 00Z TUES. STRONG Q-VECTOR
CONVERGENCE ALONG WITH FRONTOGENETIC FORCING FROM PACIFIC COLD FRONT
SUPPORT PRETTY GOOD RAIN CHANCES THIS AFTERNOON AND HAVE INCREASED
POPS...KEEPING THE HIGHEST VALUES IN THE WEST. THERMAL PROFILES
REMAIN WARM ENOUGH THROUGH THE AFTERNOON TO KEEP PRECIP AS RAIN.

THE MAIN CHALLENGE WITH THIS SYSTEM REMAINS THE CHANGEOVER FROM RAIN
TO SNOW TONIGHT AND RESULTANT SNOWFALL AMOUNTS. SIGNIFICANT COLD
AIR IS LACKING WITH THIS SYSTEM OF PACIFIC ORIGIN...AS CONFIRMED
BY H85 00Z OBS FROM LAST EVENING. HOWEVER THERE DOES APPEAR TO BE
ENOUGH COLD AIR TO SUPPORT A MIX WITH AND EVENTUAL CHANGEOVER TO
SNOW FROM WEST TO EAST THIS EVENING/OVERNIGHT...AND SOME DYNAMIC
COOLING WILL SUPPLEMENT THIS SOMEWHAT AS WELL. NEAR SURFACE TEMPS
ALSO REMAIN FAIRLY WARM HOWEVER...WHICH WILL HAMPER SNOWFALL
ACCUMULATIONS. SURFACE WETBULBS ARE ONLY FORECAST TO FALL INTO
LOWER 30S IN THE WESTERN CWA TONIGHT...WHILE STAYING IN THE MID TO
UPPER 30S IN THE EAST. HENCE EVEN THOUGH PROFILES ALOFT WILL
SUPPORT A CHANGEOVER TO SNOW...DETERMINING HOW MUCH OF THE SNOW WILL
ACCUMULATE REMAINS A CHALLENGE. BASED ON THE RELATIVELY WARM NEAR
SURFACE TEMPS AND THE FACT THAT THE COLDER AIR LAGS THE STRONGER
MID-LEVEL FORCING AND RESULTANT HIGHER QPF...THINK THAT
ACCUMULATIONS WILL REMAIN FAIRLY LIGHT. MUCH OF THE PRECIP ACROSS
THE CENTRAL AND ESPECIALLY EASTERN CWA WILL LIKELY FALL AS RAIN OR
A RAIN/SNOW MIX. HAVE KEPT THE HIGHEST ACCUMULATIONS IN THE
NORTHWEST CWA...WHERE 1-2 INCHES ARE POSSIBLE NORTHWEST OF A
FULLERTON/GRAND ISLAND/PHILLIPSBURG LINE IN THE DEFORMATION BAND
PRECIP...WITH NEAR AN INCH POSSIBLE ALONG THIS SAME
LINE...TAPERING OFF TO LITTLE TO NOTHING IN THE SOUTHEAST.
NORTHWEST WINDS WILL ALSO PICK UP TONIGHT ON THE BACKSIDE OF THE
SYSTEM...REACHING SPEEDS OF 20-30 MPH WITH GUSTS AROUND 35
MPH...WHICH MAY COMBINE WITH THE PRECIP TO PRODUCE SOME REDUCED
VSBYS.

THE DEFORMATION/WRAPAROUND RAIN/SNOW MAY LINGER IN THE EASTERN
CWA INTO TUESDAY MORNING...BUT THE SYSTEM IS PRETTY QUICK TO PULL
OUT INTO IA/MO...BRINGING AN END TO THE PRECIP BY MIDDAY. ONLY
ANTICIPATE SOME LIGHT SNOW ACCUMULATIONS IF ANY /HALF INCH OR
LESS/ IN THE EAST TUESDAY MORNING. BREEZY NORTHWEST WINDS WILL
KEEP IT ON THE COOL SIDE ON TUESDAY...ALTHOUGH CLOSE TO
SEASONAL...WITH HIGHS IN THE 40S. ANOTHER UPPER WAVE DIVES
SOUTHEAST FROM THE NORTHERN PLAINS THROUGH THE UPPER MIDWEST/MID
MS VALLEY ON WEDNESDAY...SENDING A REINFORCING COLD FRONT THROUGH
THE AREA. NOT EXPECTING ANY PRECIP WITH THIS AS A DRY LOWER 10KFT
OR SO OF THE TROPOSPHERE WILL LIKELY KEEP ANYTHING LIMITED TO
VIRGA...AT BEST A STRAY SPRINKLE OR FLURRY. HOWEVER IT WILL KEEP
TEMPS AROUND 40F NORTHEAST TO THE UPPER 40S SOUTHWEST FOR HIGHS.

DRY CONDITIONS AND SEASONAL TEMPS ARE EXPECTED ON THANKSGIVING UNDER
A NORTHWEST FLOW ALOFT...WITH TEMPERATURES THEN MODERATING LATE WEEK
INTO THE FIRST PART OF THE WEEKEND AS THE WESTERN CONUS RIDGE
PROPAGATES EAST.

&&

.AVIATION...06Z KGRI TAF. POOR AVIATION WEATHER CONDITIONS ARE
EXPECTED TO CONTINUE AT KGRI WITH LOW CEILINGS AND DENSE FOG.
THE MAIN PROBLEM WILL BE THE DENSE FOG WHICH HAS ALREADY DEVELOPED
THIS EVENING AND WILL ONLY THICKEN AND EXPAND THROUGH THE OVERNIGHT
PERIOD. VISIBILITIES WILL LIKELY RANGE FROM NEAR ZERO UP TO A
QUARTER OF A MILE UNTIL LATE MORNING. FOG AND CEILINGS WILL LIFT
SOME BY LATE MORNING INTO THE EARLY AFTERNOON WITH MVFR
CONDITIONS BY AFTERNOON. PRECIPITATION SHOULD HOLD OFF UNTIL AFTER
6 PM AND THEN BEGIN IN THE FORM OF RAIN. RAIN COULD CHANGE OVER TO
SNOW JUST BEYOND THE END OF THIS TAF VALID PERIOD AFTER MIDNIGHT
MONDAY NIGHT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR NEZ039>041-
     046>049-060>064-072>077-082>087.

KS...DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR KSZ005>007-
     017>019.

&&

$$

KB

000
FXUS63 KLBF 230927 AAA
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
327 AM CST MON NOV 23 2009

.DISCUSSION...
A FEW THINGS ARE DISCONCERNING THIS MORNING WITH RESPECT TO
PRECIPITATION CHANCES TODAY...THE EXTREMELY DRY 00Z KLBF RAOB AND
THE LACK OF STRONGER RETURNS UPSTREAM AND LIMITED METAR SITES
REPORTING SNOWFALL. MAIN AREA OF PCPN ATTM SEEMS TO LIMITED TO
NORTHERN CO ROCKIES...THOUGH STEAMBOAT IS REPORTING 1/4SM AND HEAVY
SNOW. FARTHER NORTH IN WY SNOW HAD ENDED AT MOST REPORTING STATIONS
ATTM WITH 1/2 TO 1 INCH OF NEW SNOWFALL IN LOCAL REPORTS.
OROGRAPHICS OF NORTHERN COLORADO ENHANCED BY MAIN ENERGY ROTATING
THROUGH BASE OF TROF ACROSS MUCH OF THE CENTRAL AND NORTHERN
ROCKIES...AND BY FAVORED REGION OF CYCLONIC JET MAX ALOFT. MUCH OF
THE MODEL DATA HAS COME IN TO BETTER AGREEMENT THIS MORNING IN
CLOSING OF THE MID LEVEL LOW IN VCNTY OF SW NEB/NW KS BY LATE THIS
AFTERNOON AS SYSTEM EJECTS ONTO PLAINS AND THE JET BEGINS TO REFORM
ON DOWNSTREAM SIDE OF THE CIRCULATION. THROUGH THE NEXT 12 HOURS BY
12Z TUE MAJORITY OF THE MODELS CLUSTER THE LOW...NOW BECOMING MORE
STACKED...OVER FAR NORTHEAST KANSAS. NAM AND UKMET ARE SLIGHT
OUTLIERS BY THIS TIME...AND EURO HAS BEEN MOST CONSISTENT THE PAST
FEW DAYS OF RUNS. BULK OF THE SOLNS TAKE PRECIPITATION/MOISTURE OUT
OF CO/WY ROCKIES AND SWING IT THROUGH NORTHEAST COLORADO INTO SW
NEBRASKA IN DEFORMATION ZONE OF CLOSING MID LEVEL LOW TODAY...THEN
PRECIPITATION SHOULD MOVE OFF TO THE SOUTHEAST THROUGH THE EARLY
MORNING HOURS. PATTERN WILL REMAIN FAIRLY PROGRESSIVE AS NEXT SYSTEM
ALREADY APPROACHING THE B.C. WEST COAST AND WILL BE DROPPING THROUGH
NORTHERN PLAINS AND LOWER MO VALLEY TUE NIGHT INTO WEDNESDAY. WITH
LACK OF SIGNIFICANT COLD AIR LEADING TO QUESTIONABLE P-TYPE/LIMITED
SNOW POTENTIAL AND PROGRESSIVE NATURE OF SYSTEM SEE NO REASON TO
ISSUE ANY TYPE OF HEADLINES WITH 2 INCHES OF SNOW OR LESS...MUCH
LESS...EXPECTED. MOISTURE TRANS VECTS SEEM TO INDICATE THAT WCB IS
NOT TAPPED UNTIL SYSTEM IS MORE VERTICALLY STACKED OVER NCENTRAL
KANSAS LATE TONIGHT AND ANY TROWAL POTENTIAL LOOKS WELL EAST OF THIS
CWA. ALSO CONCERNING IS PTYPE TODAY WITH MOST 00Z MODELS NOT
HANDLING THE STRONG RADIATIONAL COOLING ACROSS CENTRAL AND WESTERN
NEB OVERNIGHT. BUFKIT/PLUMES INDICATED RAIN THIS MORNING BUT STRONG
LLVL INVERSION WOULD HINT AT FZRA WITH WARM TEMPERATURES ALOFT.
HOWEVER THINK DRY LOW LAYERS WILL PREVENT MOST PCPN FROM REACHING
GROUND THROUGH MID MORNING AS LIFT IS FAIRLY WEAK AND WILL LEAVE
SNOW AS MAIN PTYPE THIS MORNING IN THE FAR WEST. THICKNESS VALUES
AND ICONS SUPPORT SNOW OVER MUCH OF TH WEST THROUGH THE AFTERNOON
WITH FAIRLY GOOD LIFT THROUGH THE DENDRITIC LAYER AFTER 18Z IN THE
SOUTHWEST PROBABLY ENOUGH TO OVERCOME DRY LOW LEVELS AND PROVIDE
COOLING FOR SNOW AS WELL. SOUNDINGS ATTM ALSO DO NOT SHOW PROLONGED
OR EVIDENT LLVL SATURATED ISOTHERMAL LAYER SO THINK SNOW SHOULD
REMAIN FAIRLY LIGHT WITH TEMPS IN THE MID TO UPPER 30S AND SURFACE
WET BULBS ABOVE FREEZING ALSO HAMPERING ACCUMULATIONS. AND LASTLY
FAIRLY BREEZY NW WIND SHOULD NOT BE REAL FAVORABLE FOR HEAVY SNOW AS
WELL. SYSTEM SHOULD BE INTO EASTERN PLAINS BY MIDNIGHT WITH BULK OF
PCPN COMING TO AN END AND S/W RIDGE BUILDS IN FOR WEDNESDAY AHEAD OF
CLIPPER DROPPING INTO DAKOTAS. WESTERLY DOWNSLOPE SHOULD HELP BRING
TEMPS BACK UP TO NEAR NORMAL IN THE MID TO UPPER 40S AND USED BLEND
OF GUIDANCE. EXPECT CLIPPER TO COME THROUGH DRY THOUGH FEW FLURRIES
POSSIBLE DOWNSTREAM FROM HILLS ACROSS NW CWA WITH JET MAX ALOFT AS
WELL. CAA AND BREEZY CONDITIONS BEHIND FRONT ON WEDNESDAY WILL BRING
BLUSTER DAY FOR THE NORTH CENTRAL. UPPER RIDGE WILL AMPLIFY IN WEST
BY THURSDAY...BUT KEEP COOLER AIR IN EASTERN CWA FOR THANKSGIVING
WILL WARMUP WILL BEGIN IN WEST AND CONTINUE EASTWARD FOR FRIDAY WITH
DRY WEATHER EXPECTED.

&&

.AVIATION...
THE BULK OF AVIATION FORECAST CONCERNS WILL LIE AT THE KLBF TERMINAL
TODAY AND TONIGHT AS AN UPPER LEVEL LOW LIFTS EAST ALONG THE KANSAS
AND NEBRASKA BORDER. THROUGH MID MORNING...LIFR CEILINGS AND
VISIBILITIES ARE LIKELY AT THE KLBF TERMINAL AS LOW LEVEL
MOISTURE...ADVECTS WWD FROM CENTRAL NEBRASKA. THIS LOW LEVEL
MOISTURE IS EXPECTED TO REMAIN SOUTH AND EAST OF THE KVTN TERMINAL
THIS MORNING...SO ONLY MID TO HIGH LEVEL CLOUDINESS IS EXPECTED ATTM
AT THAT LOCATION. LIFR CEILINGS ARE EXPECTED TO LIFT BY LATE
MORNING...AND BE REPLACED BY OVERCAST MID TO HIGH LEVEL CLOUDINESS.
NORTHERLY WINDS WILL INCREASE BEHIND A FRONTAL BOUNDARY...WHICH IS
EXPECTED TO PASS THROUGH THE KLBF AND KVTN TERMINALS DURING THE
16-20Z TIME FRAME. LIGHT RAIN...AND OR SNOW...WILL DEVELOP LATER
THIS AFTERNOON AND THIS EVENING AT THE KLBF TERMINAL IN ASSOCIATION
WITH THE BEFORE MENTIONED UPPER LEVEL LOW. BASED ON THE LATEST
GUIDANCE AND MODEL TRENDS...21Z TO 03Z WILL SEE THE GREATEST THREAT
FOR PRECIPITATION WITH VISIBILITIES BRIEFLY DOWN TO A MILE AND
CEILINGS RANGING FROM 1000 TO 2000 FT AGL. FLT CONDS WILL IMPROVE
AFTER 06Z TONIGHT...AS THE UPPER LEVEL LOW TRACKS INTO NERN KS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

13/CLB

000
FXUS63 KOAX 230915
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
315 AM CST MON NOV 23 2009

.DISCUSSION...

MAIN FORECAST CONCERN/FOCUS REMAINS COMPACT UPPER LOW THE MODELS
STILL FORECAST TO CLOSE OFF OVER THE PLAINS TNGT. 00Z ECMWF/GFS
FORECAST THE UPPER LOW NEAR THE SW NEBR/NW KS VCNTY BY THIS
EVENING AND THEN TRACK IT NEAR THE NEBR/KS BORDER TUE BEFORE
MOVING IT INTO NERN MO BY 00Z WED. ALTHOUGH THERE IS GENERAL MODEL
AGREEMENT ON THIS...THE ECMWF HAS BEEN THE MOST CONSISTENT AND HAD
DECENT SUPPORT FROM 21Z SREF/00Z GFS AND WAS MOSTLY FOLLOWED IN
ITS HANDLING OF THE SYSTEM/QPF. THE 00Z NAM...ALTHOUGH CLOSE TO
OTHERS...WAS A BIT S/SW WITH 500 MB TRACK/QPF PLACEMENT AND WAS A
MODEST OUTLIER.

OVERNIGHT STLT IMAGERY SHOWED BROAD TROUGH OVR ROCKIES WITH LAST
EVENINGS UA INDICATING 100+ KT JET AT 300 MB DIGGING SEWD FM WA
INTO WRN UT. MODEST HEIGHT FALLS WERE NOTED...WITH 10 DM OR MORE
AT 300 MB AT RIW/SLC/ELKO AND BOI. MOISTURE AHEAD OF THE
SYSTEM...ALTHOUGH ABOVE CLIMO FOR LATE NOVEMBER...WAS A BIT MODEST
WITH SFC DWPTS IN THE 40S F AND 850 MB DWPTS...OUTSIDE OF COASTAL
SITES...MOSTLY AOB 5 DEG C. ALTHOUGH MOST OF THE FORCING FROM THIS
SYSTEM WON/T ARRIVE UNTIL TNGT/TUE...SOME ISENTROPIC UPGLIDE WAS
FORECAST...SPCLY THIS AFTN...OVR NERN AND FAR WRN ZONES. KEPT IN
HIGHER POPS THOSE AREAS THIS AFTN SINCE CONDENSATION PRESSURE
DEFICITS WERE LOWER THERE. TAPERED POPS OFF TO SLGT CHC FAR SE
WHERE LIFT WAS WEAKER AND MID LVL MOISTURE MORE ABSENT. LTL/NO
CHANGES MADE TO MAX TEMPS WITH READINGS RANGING FM UPR 40S FAR NW
TO MID/UPR 50S SERN 1/2 WHERE MILD START AND SOME OCNL BINOVC
COULD PREVAIL. CLOUDS HAVE GENERALLY KEPT VSBYS FROM FALLING TOO
LOW THIS MORNING...ALTHOUGH SOME PATCHY DENSE FOG WAS REPORTED W
OF LNK. ATTM NO ADVSRY FOR FOG PLANNED BUT WL CARRY PATCHY MENTION
OF IT W AND S THIS MORNING.

FOR TNGT/TUE...500/700 MB LOW TRACK ALONG NRN KS INTO
NERN KS BY 12Z TUE AND THEN INTO NERN MO BY 00Z WED WOULD PLACE
HIGHEST PCPN BAND IN OUR CWA NEAR THE I80 CORRIDOR...ALTHOUGH
MODELS WANT TO CONT TO FCST A SECONDARY QPF MAX FARTHER NE TUE
AFTN. GENERALLY PLACED HIGHEST QPF FM SW TO NE THRU THE OMA/LNK
METROS BUT WITH SPEED OF SYSTEM AND SUBJECTIVE VIEW OF MOISTURE
AVAILABLE...AMOUNTS WERE PLACED MORE IN A COMPROMISE OF HIGHER
GFS/ECMWF VS. LOWER SREF TOTALS. NONETHELESS...STORM TOTALS OVER 1
INCH APPEAR QUITE PROBABLE...WHICH FOR A LATE NOVEMBER STORM IS
DECENT AND WOULD THEN LEAD TO WHAT DO TEMPERATURE PROFILES LOOK
LIKE. GENERAL MODEL TRENDS HAVE BEEN FOR THICKNESSES AND 850 MB
TEMPS TO MODERATE/WARM A BIT. PLUS CURRENT FORECAST SOUNDINGS FM
GFS/ECMWF...ALTHOUGH ECMWF MORE LIMITED IN LVLS/TIME PDS...ALSO
ONLY MODESTLY SUPPORT A POSSIBLE CHANGE TO SNOW FAR WRN CWA MOSTLY
ON NWRN/WRN FLANK OF PCPN SHIELD TOWARD AND A LTL AFT 12Z TUE.
THUS LIMITED MENTION OF SNOW TO FAR WRN ZONES WITH ANY AMOUNTS 1
INCH OR LESS. SYSTEM STILL BEARS WATCHING THOUGH AS THERE COULD BE
A NARROW AREA WHERE ACCUMULATIONS EXCEED THIS BUT OVER ALL PCPN
TYPE APPEARS WILL REMAIN LIQUID. USING SLIGHTLY SLOWER ECMWF WOULD
KEEP MOST OF THE OVERNIGHT COLD ADVCTN OVR WRN CWA. SO RAISED LOWS
E A BIT. WITH SYSTEM MOVG INTO NERN MO LATE IN THE DAY...A
DECREASE/END IN PCPN AND EVEN SOME BRIGHTENING SKIES WRN ZONES
ALONG WITH THE SLIGHTLY MILDER START TO THE DAY E BUMPED UP HIGHS
MOST AREAS...ALTHOUGH STILL KEPT A TIGHT DIURNAL RANGE.

BASICALLY MADE LTL CHANGES TO TUE NGT THRU THU PD. A TRAILING
UPPER TROUGH/LOW DROPS QUICKLY INTO IA BY 00Z THU AIDING IN
EJECTING FIRST LOW AND ENDING MOST PCPN EARLY TUE NGT. LEFT IN
SMALL SNOW CHCS WITH THIS TRAILING LOW FAR ERN ZONES AS MOST OF
THE FORCING AND QPF SHOULD REMAIN TO OUR E. PRETTY GOOD AGREEMENT
BETWEEN 00Z ECMWF/GFS WITH THIS NEXT SYSTEM. LOOKS BLUSTERY AND
COOL...HOWEVER...WITH STRATOCU POSSIBLY LINGERING WELL INTO THU
ERN ZONES. MAX TEMPS COULD STRUGGLE TO GET MUCH ABOVE 40 ERN
ZONES WED/THU ACCORDING TO FCST GFS SOUNDINGS.

MODERATING TREND STILL ON TRACK FRI/SAT BEFORE NEXT TROUGH LATE
NEXT WEEKEND. NO CHANGES MADE THOSE PDS.

&&

.AVIATION...
TAF SITES KOFK/KOMA/KLNK

06Z TAFS

WEAK STATIONARY BOUNDARY LOCATED IN CENTRAL NEBRASKA ON WESTERN EDGE
OF THE FA THIS MORNING EXPCTED TO MOVE VERY LITTLE THROUGH THE DAY
AS LOW PRESSURE DEVELOPS OVER THE SOUTHERN PLAINS. MOST VARIABLE
CONDITIONS EXPECTED AT KOFK CLOSEST TO THE BOUNDARY. VFR TO MVFR CONDITIONS
EXPECTED AT KLNK AND KOMA UNTIL FRONT BEGINS TO MOVE IN AFTER 00Z WITH
CONDITIONS BECOMING IFR OR LIFR CIGS AND VSBYS IN FOG AND SHOWERS.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$

CHERMOK/FOBERT

000
FXUS63 KGID 230454
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1054 PM CST SUN NOV 22 2009

.AVIATION...06Z KGRI TAF. POOR AVIATION WEATHER CONDITIONS ARE
EXPECTED TO CONTINUE AT KGRI WITH LOW CEILINGS AND DENSE FOG.
THE MAIN PROBLEM WILL BE THE DENSE FOG WHICH HAS ALREADY DEVELOPED
THIS EVENING AND WILL ONLY THICKEN AND EXPAND THROUGH THE OVERNIGHT
PERIOD. VISIBILITIES WILL LIKELY RANGE FROM NEAR ZERO UP TO A
QUARTER OF A MILE UNTIL LATE MORNING. FOG AND CEILINGS WILL LIFT
SOME BY LATE MORNING INTO THE EARLY AFTERNOON WITH MVFR
CONDITIONS BY AFTERNOON. PRECIPITATION SHOULD HOLD OFF UNTIL AFTER
6 PM AND THEN BEGIN IN THE FORM OF RAIN. RAIN COULD CHANGE OVER TO
SNOW JUST BEYOND THE END OF THIS TAF VALID PERIOD AFTER MIDNIGHT
MONDAY NIGHT.

&&

.PREV DISCUSSION... /ISSUED 903 PM CST SUN NOV 22 2009/

UPDATE...FOG IS RAPIDLY DEVELOPING THIS EVENING AND BECOMING
DENSE IN SOME LOCATIONS. WINDS WILL REMAIN LIGHT THROUGH THE NIGHT
AND LOW LEVEL MOISTURE WILL CONTINUE TO BE HIGH.
THEREFORE...EXPECT FOG WILL ONLY BECOME MORE DENSE AND WIDESPREAD
ACROSS THE REGION AS WE HEAD THROUGH THE NIGHT AND INTO TOMORROW
MORNING. CONSEQUENTLY...HAVE ISSUED A DENSE FOG ADVISORY FOR ALL
AREAS.

ALSO OF NOTE...THE 00Z NAM IS NOW AVAILABLE AND LIKE THE 18Z NAM IS THE
FURTHEST SOUTH FORECAST MODEL WITH OUR STORM SYSTEM TO IMPACT THE
AREA MONDAY NIGHT. IT SHOULD BE NOTED THAT THE 21Z SREF...SHORT
RANGE ENSEMBLES...SUPPORT A MORE NORTHERLY TRACK THAN THE
OPERATIONAL NAM. THE SREF SHOWS A MEAN 500MB TRACK ACROSS THE
NEBRASKA/KANSAS BORDER MONDAY NIGHT...WHICH IS MORE IN LINE WITH
THE 12Z ECMWF...AND THE 18Z GFS. THIS POINTS TO THE CONTINUED
THREAT OF A DECENT RAIN AND/OR SNOW EVENT ACROSS PORTIONS OF OUR CWA
MONDAY NIGHT.

PREV DISCUSSION... /ISSUED 322 PM CST SUN NOV 22 2009/

SHORT TERM...TONIGHT THROUGH 12Z WEDNESDAY. MAIN FORECAST
CONCERN WILL BE STORM SYSTEM THAT AFFECTS THE AREA MONDAY THROUGH
TUESDAY.

CLOUDS WILL PERSIST THOUGH THE NIGHT AND EXPECT FOG TO REDEVELOP
AGAIN. SOME AREAS NEAR ADVISORY CRITERIA POSSIBLE...BUT TOO
DIFFICULT TO PIN POINT TO ISSUE ONE AT THIS TIME. DRIER AIR TRYING
TO WORK IN FROM THE WEST...BUT FEEL IT WILL NOT MAKE TOO MUCH
PROGRESS. WINDS HAVE BEEN TRYING TO SWITCH TO THE NORTHWEST AT KGRI
BUT HAVE RETURNED TO THE SOUTHEAST. SO BOUNDARY WILL BE SLOW TO MOVE
EAST IF AT ALL BEFORE IT WASHES OUT. SOME LIGHT PRECIP NOTED ON KUEX
AND AT GID...SO WILL GO WITH ISOLATED SHOWERS LATE THIS AFTERNOON
AND THESE SHOULD END SHORTLY AFTER SUNSET.

MODELS ARE COMING INTO BETTER AGREEMENT THIS AFTERNOON IN BRINGING
AN UPPER LOW OUT OF THE ROCKIES AND INTO NORTHERN KANSAS MONDAY AND
MONDAY NIGHT...THEN INTO IOWA AND MISSOURI BY TUESDAY EVENING.

A WEAK SURFACE FRONT WILL MOVE THROUGH THE FORECAST AREA MONDAY
MORNING BUT THE PRECIPITATION DOES NOT DEVELOP UNTIL THE UPPER LOW
APPROACHES FROM THE WEST. THERE IS A SLIGHT CHANCE THAT THE RAIN
WILL START MONDAY MORNING IN THE WESTERN PART OF THE FORECAST AREA
BUT THE BETTER CHANCE WILL BE AFTERNOON AS THE UPPER LOW APPROACHES.

THE BIGGEST ISSUE WITH THE FORECAST WILL BE IF AND WHEN THE RAIN
CHANGES OVER TO SNOW. THE GFS IS COLDER WHILE THE NAM IS WARMER. THE
ECMWF IS ALSO ON THE COOLER SIDE SO EXPECT THAT THE PRECIPITATION
WILL EVENTUALLY CHANGE OVER TO SNOW OR AT THE VERY LEAST MIX WITH
SNOW IN THE EASTERN PART OF THE FORECAST AREA. IN THE WEST WHERE THE
AIR IS THE COOLEST RAIN WILL MIX WITH SNOW DURING THE EVENING AND
CHANGE OVER LATER IN THE EVENING AND OVERNIGHT IN THE CENTRAL PART
OF THE FORECAST AREA.

MODELS ARE FAIRLY CONSISTENT IN KEEPING THE LOW MOVING THROUGH AND
INTO IOWA OR MISSOURI ON TUESDAY. THERE COULD BE A LITTLE RAIN OR
SNOW THAT WILL CONTINUE IN THE FAR EAST DURING THE MORNING TUESDAY
BUT BY AFTERNOON THE PRECIPITATION SHOULD BE GONE. AS THE LOW MOVES
TO THE EAST COOLER AIR MOVES INTO THE AREA TUESDAY NIGHT WITH NORTH
WINDS.

LONG TERM...12Z WEDNESDAY THROUGH SUNDAY. ONCE UPPER SYSTEM GOES BY
QUESTION THEN BECOMES WILL THERE BE A SECOND SYSTEM ON THE HEELS OF
THE FIRST. MODELS ALL TEND TO BRING SOMETHING ON THE BACKSIDE OF
MAIN WAVE. THEY DO DIFFER ON IF COLD AIR GETS PUSHED BACK TO THE
WEST AND FOR HOW LONG.  DO BELIEVE THAT WEDNESDAY AND THURSDAY WILL
BE COOL AND THEN WARMING UP FOR FRIDAY AND SATURDAY AS A RIDGE
BUILDS IN THE UPPER LEVELS. NO WEATHER WILL BE ASSOCIATED WITH THE
SECOND WAVE OTHER THAN SOME CLOUDS...BUT IT SHOULD BE DRY THROUGH
THE PERIOD.  HIGHS WEDNESDAY AND THURSDAY TO BE IN THE 40S AND THE
50S FOR FRIDAY AND SATURDAY. THE NEXT SYSTEM TO MOVE INTO THE AREA
SATURDAY EVENING AND PUSH A FRONT THROUGH. THIS WILL COOL THINGS
BACK OFF INTO THE 40S.  RIGHT NOW IT LOOKS DRY FOR THIS SYSTEM AS
WELL.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 11 AM CST MONDAY FOR NEZ039>041-046>049-
     060>064-072>077-082>087.

KS...DENSE FOG ADVISORY UNTIL 11 AM CST MONDAY FOR KSZ005>007-017>019.

&&

$$