000
FXUS63 KFGF 222128
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
328 PM CST SUN NOV 22 2009

.SHORT TERM...TONIGHT THROUGH WEDNESDAY

PRIMARY FORECAST CHALLENGES INCLUDE TEMPERATURES AND PRECIPITATION
CHANCES WITH THE NEXT STORM SYSTEM TO IMPACT THE REGION MONDAY
THROUGH WEDNESDAY. 12 UTC GFS/NAM/ECMWF IN REASONABLE AGREEMENT
AND WILL UTILIZE A MODEL BLEND FOR THIS FORECAST PACKAGE.

21 UTC WATER VAPOR LOOP SHOWS SHORT WAVE ALOFT MOVING INTO EASTERN
NORTH DAKOTA. AT THE SURFACE...TROUGH AXIS STRETCHES FROM THE MN
ARROWHEAD TO NEAR SIOUX FALLS SD WITH WEAK HIGH PRESSURE MOVING
ACROSS THE DAKOTAS. FOR TONIGHT...MID-HIGH LEVEL CLOUDS AHEAD OF
UPPER WAVE WILL MOVE EAST WITH CLEARING SKIES. HOWEVER...CLOUDS
WILL BE ON THE INCREASE ACROSS THE SOUTHERN FORECAST AREA BY
DAYBREAK IN RESPONSE TO THE NEXT LOW PRESSURE SYSTEM. LOWS WILL
RANGE FROM THE LOW TO MID 20S ACROSS THE DEVILS LAKE BASIN TO THE
MID 30S ACROSS WEST CENTRAL MN WHERE CLOUD COVER WILL BE GREATEST.

ATTENTION THEN TURNS TO EASTERN PACIFIC WAVE THAT CRASHED ONSHORE
THIS MORNING. MODELS IN GOOD AGREEMENT SHOWING THIS SYSTEM DROP
SOUTH ACROSS THE CENTRAL PLAINS TUESDAY AND INTO THE GREAT LAKES
REGION WEDNESDAY. THE ECMWF IS A BIT SLOWER THAN THE MORE
PROGRESSIVE GFS...BUT BOTH MODELS MAINTAIN 925 HPA TEMPERATURES AT
OR ABOVE 0 C THROUGH TUESDAY. AS SUCH...THINK THE PRECIPITATION
THAT FALLS WILL BE MOSTLY RAIN...WITH PERHAPS SOME LIGHT SNOW
MIXED IN DURING THE EARLY MORNING HOURS ON THE WESTERN FLANK OF
THE PRECIPITATION SHIELD.

MAJORITY OF PRECIPITATION LOOKS TO IMPACT NORTHWEST AND WEST
CENTRAL MN AS SURFACE INVERTED TROUGH/LOW-LEVEL CONVERGENCE SETS-
UP ALONG AND TO THE EAST OF THE RED RIVER. UPPER LEVEL FORCING IS
UNIMPRESSIVE...BUT SOUTHERLY FLOW AHEAD OF THE LOW SHOULD ADVECT
MID-30 DEW POINT AIR INTO THE REGION. WITH PRECIPITABLE WATER
VALUES BETWEEN 0.5 AND 0.75 INCHES...THE ATMOSPHERIC COLUMN SHOULD
SATURATE QUICKLY BY MONDAY AFTERNOON. LIGHT RAIN IS LIKELY ACROSS
MUCH OF NORTHWEST AND WEST CENTRAL MINNESOTA MONDAY AFTERNOON
THROUGH EARLY TUESDAY MORNING WITH THREE TO FOUR TENTHS OF
ACCUMULATION. AN ADDITIONAL TENTH OR TWO IS POSSIBLE IN THESE
AREAS DURING THE DAY TUESDAY. AREAS ALONG THE RED RIVER WILL SEE
A TENTH OR LESS AT BEST WITH MUCH OF EASTERN NORTH DAKOTA STAYING
DRY.

925-850 HPA TEMPERATURES DROP WELL BELOW FREEZING TUESDAY NIGHT
AND WEDNESDAY AS A SECONDARY SHORT WAVE DROPS SOUTH ACROSS THE
EASTERN DAKOTAS. PRECIPITATION SHOULD CHANGE OVER TO ALL SNOW BY
WEDNESDAY MORNING WITH THE POTENTIAL FOR SOME SPOTS EAST OF THE
RED RIVER TO ACCUMULATE UP TO TWO INCHES OF FRESH SNOW. EXPECT
BREEZY TO LOCALLY WINDY CONDITIONS AS DECENT COLD AIR ADVECTION IS
ACCOMPANIED BY STRONG NORTHWEST FLOW ALOFT. TEMPERATURES WEDNESDAY
WILL STRUGGLE TO REACH THE MID 30S.

.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT SUNDAY

MODELS HAVING DIFFICULTY WITH PROGRESSION OF SYSTEMS IN EXTENDED
PERIOD. HOWEVER...ECMWF HAS BEEN THE MOST CONSISTENT AND IS THE
BLEND SOLN BETWEEN GFS/DGEX SO STAYED WITH IT ATTM. 500MB RIDGE
SHIFTS OVER THE AREA KEEPING TEMPS A BIT ABOVE SEASONAL NORMS FOR
THE THU/FRI TIMEFRAME. OTHERWISE...PATTERN LOOKS TO REMAIN
PROGRESSIVE AS A COLD FRONT IS EXPECTED TO CROSS THE FA BY SAT
BRINGING COOLER TEMPS AND A CHANCE FOR PCPN.

&&

.AVIATION...

EXPECT VFR CONDITIONS TO PREVAIL UNTIL AFTER 12Z MON WHERE
GREATEST CHANCES FOR MVFR/IFR CIGS WILL BE IN SE W-CNTRL MN.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

ROGERS/HOPKINS

000
FXUS63 KBIS 222034
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
235 PM CST SUN NOV 22 2009

.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...

CONTINUED MILD MONDAY AND TUESDAY...WITH COOLER AND WINDY CONDITIONS
BEGINNING TUESDAY NIGHT AND INTO WEDNESDAY NIGHT. TEMPERATURES
REBOUNDING FOR THURSDAY FOR A MILD AND TRANQUIL THANKSGIVING DAY.

LATEST WATER VAPOR IMAGERY SHOWS THE SHORTWAVE ALOFT MOVING EAST
ACROSS THE STATE THIS AFTERNOON...AND THE NEXT SHORTWAVE IN THE
UPPER LEVEL FLOW TO AFFECT OUR REGION OVER EASTERN
WASHINGTON/OREGON.

SHORT RANGE MODELS BRING THE LOW CENTER OF THIS NEXT SHORTWAVE OVER
SOUTHEASTERN MONTANA BY MONDAY MORNING...AND THE LOW TROUGH
EXTENDING FROM SOUTH CENTRAL CANADA TO THE LOW CENTER OVER THE
CENTRAL PLAINS NEAR NEBRASKA/KANSAS BY MONDAY EVENING. MORE
MID/UPPER LEVEL MOISTURE ASSOCIATED WITH THIS NEXT SHORTWAVE AND
WILL KEEP THE SLIGHT CHANCE MENTION OF RAIN OR SNOW OVER SOUTHERN
COUNTIES ON MONDAY. TEMPERATURES MONDAY AND TUESDAY REMAINING ABOVE
AVERAGE FOR THIS TIME OF YEAR...WITH HIGHS IN THE 40S AND LOWS IN
THE TEENS AND 20S.

A STRONGER UPPER LEVEL SHORTWAVE MOVES SOUTHEAST OUT OF ALBERTA AND
INTO NORTHWESTERN NORTH DAKOTA LATE TUESDAY AFTERNOON. THE SURFACE
LOW ASSOCIATED WITH IT MOVES QUICKLY FROM SASKATCHEWAN/MANITOBA
TUESDAY AFTERNOON TO THE GREAT LAKES AREA BY WEDNESDAY MORNING. THE
MODELS ARE DEPICTING A STRONG NORTH-SOUTH ORIENTED UPPER LEVEL JET
FROM ALBERTA TO EASTERN MONTANA TUESDAY AFTERNOON...TO
SASKATCHEWAN/EASTERN MONTANA/WESTERN DAKOTAS WEDNESDAY MORNING...TO
MANITOBA/DAKOTAS WEDNESDAY AFTERNOON...TO THE RED RIVER VALLEY BY
THURSDAY MORNING. THIS CLIPPER AND ASSOCIATED STRONG UPPER LEVEL JET
WITH SPEEDS OF UP TO 130 KNOTS WILL ACT TO BRING STRONG
NORTH/NORTHWEST WINDS AND COLD AIR INTO THE STATE TUESDAY NIGHT
THROUGH WEDNESDAY EVENING. CHANGE IN THE HIGH TEMPERATURES ON
WEDNESDAY TO HIGHS IN THE 30S AND WINDY CONDITIONS...WITH LOWS
WEDNESDAY NIGHT AROUND 15 TO 20 DEGREES.


.LONG TERM...THURSDAY THROUGH SUNDAY NIGHT...

FORECAST CONCERNS CENTER AROUND PRECIPITATION CHANCES AS
MODEL/ENSEMBLE SPREAD INCREASES SIGNIFICANTLY SATURDAY AND SUNDAY.
ALSO NOTEWORTHY...IS HOW LONG THE ABOVE AVERAGE TEMPERATURES WILL
REMAIN OVER THE NORTHERN PLAINS.

A BROAD NEGATIVE HEIGHT ANOMALY CENTERED OVER THE BERING SEA
CONTINUES TO DIRECT SHORTWAVE ENERGY INTO WESTERN NORTH
AMERICA...RESULTING IN STEADY EASTWARD PROGRESSION OF WAVES. ONE
WAVE IN PARTICULAR PASSES THROUGH THE NORTHERN PLAINS ON SATURDAY.
THE 12 UTC GFS AND A COUPLE OF THE 12 UTC GEFS ENSEMBLE MEMBERS
CLOSE OFF A 500 HPA LOW OVER THE DAKOTAS...WHILE THE 00 UTC ECMWF
STAMPS THE LOW IN THE FOUR CORNERS REGION AND PHASES IT LESS WITH
NORTHERN STREAM ENERGY CLOSER TO HOME IN CENTRAL CANADA. THERE IS
ABOVE AVERAGE UNCERTAINTY WITH THIS FEATURE AS TRACK AND INTENSITY
ARE IN QUESTION. PRECIPITATION SEEMS LIKE A REASONABLE POSSIBILITY
FROM BOTH SOLUTIONS...BUT WOULD BE FAR LESS WIDESPREAD WITH THE
ECMWF SOLUTION. HPC HAS LEANED MORE HEAVILY ON THE 00 UTC ECMWF WITH
ITS MORE CONSISTENT FORECASTS OF THIS FEATURE...BUT WITH SUCH HUGE
ENSEMBLE SPREAD...GRIDDED FORECASTS WILL INDICATE ONLY A SLIGHT
CHANCE OF PRECIPITATION.

LOOKING AT THE LATITUDINAL VARIATION IN TEMPERATURES OVER NORTH
AMERICA...THERE IS LESS BAROCLINICITY THAN DURING A NORMAL NOVEMBER.
THIS IS CHARACTERISTIC WITH NORTH AMERICAN FLOW DURING AN EL NINO
YEAR. IT IS WORTH NOTING THAT VERY COLD TEMPERATURES CONTINUE TO
INVADE MONGOLIA AND NORTHEASTERN CHINA. WITH ALMOST ALL TEMPERATURES
ABOVE ZERO DEGREES SOUTH OF 60N IN THE WESTERN
HEMISPHERE...TEMPERATURES SHOULD REMAIN ABOVE AVERAGE FOR AT LEAST
ANOTHER WEEK...THOUGH SOME SHORT TERM DIPS TO BELOW AVERAGE
TEMPERATURES ARE POSSIBLE WITH ANY DYNAMICALLY VIGOROUS SHORTWAVES
THAT PASS THROUGH THE NORTHERN PLAINS.

&&

.AVIATION...

SURFACE HIGH PRESSURE OVER THE DAKOTAS TODAY WILL SLIDE EASTWARD
THIS EVENING AS WINDS BACK TO SOUTHEASTERLY IN ADVANCE OF ANOTHER
WEAK LOW PRESSURE SYSTEM AND ASSOCIATED TROUGH. THE LATTER FEATURE
WILL MAKE PINNING DOWN WIND DIRECTIONS DIFFICULT...ESPECIALLY WITH
MAGNITUDES OF WINDS BEING GENERALLY LESS THAN 10 KNOTS. THE TROUGH
SHOULD MOVE VERY SLOWLY EASTWARD THROUGH MONDAY. CONCERNING
CLOUDS...VFR CONDITIONS WILL PERSIST WITH A BROKEN MIDDLE LEVEL DECK
POSSIBLE AS THE TROUGH PROVIDES A WEAK FOCUS FOR CLOUDS.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$


SHORT TERM...JV
LONG TERM/AVIATION...SCHECK

000
FXUS63 KFGF 221604 AAA
AFDFGF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GRAND FORKS ND
1004 AM CST SUN NOV 22 2009

.DISCUSSION...

PRIMARY CHALLENGE FOR THE MORNING UPDATE CONCERNS CLOUD TRENDS AND
TEMPERATURES. 1530 UTC WATER VAPOR LOOP SHOWS UPPER SHORT WAVE
MOVING INTO CENTRAL NORTH DAKOTA WITH A SURFACE TROUGH AXIS FROM
NEAR SIOUX FALLS TO INTERNATIONAL FALLS. PATCHY DENSE FOG ACROSS
THE ROLLING HILLS OF WEST CENTRAL MINNESOTA SHOULD BURN OFF WITHIN
THE NEXT HOUR OR SO WITH INCREASED SOLAR AND LOW-LEVEL DRYING. SCT-
BKN MID-HIGH CLOUDS EXIST ALONG A LINE FROM PIERRE TO JAMESTOWN
TO LANGDON AND ARE MOVING NORTHEAST OUT AHEAD OF APPROACHING
SHORT WAVE.

FOR TODAY...RIGHT ENTRANCE REGION OF 300 HPA 100 KT JET STREAK TO
MOVE OVERHEAD WITH PASSAGE OF UPPER-LEVEL SHORT WAVE. JET STREAK
EXPECTED TO ENHANCE NARROW BAND OF LOW-LEVEL SATURATION/LIFT ALONG
290 K ISENTROPIC SURFACE FROM NEAR PIPESTONE TO HIBBING MN THIS
AFTERNOON. HOWEVER...GFS/NAM SOUNDINGS SUGGEST NEAR-SURFACE COLUMN
TO DRY ACROSS EASTERN FORECAST AREA THROUGH THE DAY...SO MAINTAINED
A DRY FORECAST. HOWEVER...WEAK 925 HPA COLD AIR ADVECTION...COMBINED
WITH MID-HIGH LEVEL CLOUD COVER AHEAD OF UPPER WAVE SHOULD HELP
HOLD TEMPERATURES DOWN A FEW DEGREES...ESPECIALLY ACROSS PORTIONS
OF NORTHWEST AND WEST CENTRAL MINNESOTA. AS SUCH...DECREASED HIGH
TEMPERATURES TODAY AROUND 2-3 DEGREES INTO THE MID TO UPPER 40S.

REST OF THE FORECAST IN GOOD SHAPE WITH ONLY MINOR CHANGES TO
CLOUD GRIDS TO ACCOUNT FOR CURRENT SATELLITE TRENDS.

&&

.AVIATION...

SOME PATCHY FOG WAS OCCURRING ALONG AND E OF A LINE FROM BJI TO DTL
TO FFM. AS DRIER AIR PUSHES E...EXPECT FOG TO DISSIPATE. OTHERWISE...
EXPECT VFR CONDITIONS TO PREVAIL UNTIL AFTER 12Z MON WHERE GREATEST
CHANCES FOR MVFR/IFR CIGS WILL BE ACROSS W-CNTRL MN.

&&

.PREV DISCUSSION... /ISSUED 428 AM CST SUN NOV 22 2009/

SHORT TERM...TODAY THROUGH TUESDAY NIGHT.
PROGRESSIVE UPPER AIR PATTERN CONTINUES. WATER VAPOR LOOP SHOWING
SEVERAL UPSTREAM SHORT WAVES. A SHORT WAVE TROUGH EXTENDED FROM
SASK TO CO. OTHER SHORT WAVE WERE LOCATED OFF THE PACIFIC NORTHWEST
COAST AND THE NORTHEAST PACIFIC. ECMWF, GFS AND NAM IN REASONABLE
AGREEMENT THROUGH 84 HOURS. ECMWF WAS A BIT SLOWER THAN THE GFS AND
NAM. GFS AND NAM WERE SIMILAR AT 84 HOURS. WILL USE THE GFS.

SHORT WAVE TROUGH TO THE WEST WILL MOVE THROUGH THIS AFTERNOON. ONLY
MID AND HIGH CLOUDS EXPECTED WITH THE TROUGH.

NEXT WAVE OFF THE PACIFIC NORTHWEST COAST WILL MOVE INTO THE PLAINS
MON. MOISTURE MOVES NORTH MON AND TUE. PRECIPITATION EXPECTED MAINLY
ON THE MN SIDE OF THE RED RIVER.

THIRD SHORT WAVE IN THE NORTHEAST PACIFIC FORECAST INTO THE NORTHERN
PLAINS OUT OF CANADA LATE IN THE PERIOD.

LONG TERM...WEDNESDAY AND THURSDAY.
ECMWF REMAINS A SLOWER SOLUTION COMPARED TO THE GFS THIS PERIOD AND
IS PREFERRED.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

ROGERS/HOPPES

000
FXUS63 KFGF 221028
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
428 AM CST SUN NOV 22 2009

.SHORT TERM...TODAY THROUGH TUESDAY NIGHT.
PROGRESSIVE UPPER AIR PATTERN CONTINUES. WATER VAPOR LOOP SHOWING
SEVERAL UPSTREAM SHORT WAVES. A SHORT WAVE TROUGH EXTENDED FROM
SASK TO CO. OTHER SHORT WAVE WERE LOCATED OFF THE PACIFIC NORTHWEST
COAST AND THE NORTHEAST PACIFIC. ECMWF, GFS AND NAM IN REASONABLE
AGREEMENT THROUGH 84 HOURS. ECMWF WAS A BIT SLOWER THAN THE GFS AND
NAM. GFS AND NAM WERE SIMILAR AT 84 HOURS. WILL USE THE GFS.

SHORT WAVE TROUGH TO THE WEST WILL MOVE THROUGH THIS AFTERNOON. ONLY
MID AND HIGH CLOUDS EXPECTED WITH THE TROUGH.

NEXT WAVE OFF THE PACIFIC NORTHWEST COAST WILL MOVE INTO THE PLAINS
MON. MOISTURE MOVES NORTH MON AND TUE. PRECIPITATION EXPECTED MAINLY
ON THE MN SIDE OF THE RED RIVER.

THIRD SHORT WAVE IN THE NORTHEAST PACIFIC FORECAST INTO THE NORTHERN
PLAINS OUT OF CANADA LATE IN THE PERIOD.

.LONG TERM...WEDNESDAY AND THURSDAY.
ECMWF REMAINS A SLOWER SOLUTION COMPARED TO THE GFS THIS PERIOD AND
IS PREFERRED.

&&

.AVIATION...
SOME PATCHY FOG WAS OCCURRING ALONG SURFACE TROUGH AXIS. EXPECT
PATCHY FOG EAST OF A LINE FROM WESTERN ROSEAU COUNTY TO NEAR OAKES
ND EARLY THIS MORNING. REST OF 24 HOUR PERIOD, EXPECT BANDS OF
CIRRUS CLOUDS TO MOVE THROUGH. SOME CIGS AROUND 10 THOUSAND FT IN
SOUTHERN ZONES. OTHERWISE MVFR OR IFR CONDITIONS POSSIBLY MOVING
INTO FAR SOUTHEAST ZONES AFTER 12Z MON.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.

&&

$$

HOPPES

000
FXUS63 KBIS 220819
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
208 AM CST SUN NOV 22 2009

.SHORT TERM...TODAY THROUGH TUESDAY NIGHT...
LATEST WATER VAPOR IMAGERY SHOWS A PROGRESSIVE FLOW IN ACTION WITH
A SHORTWAVE TROUGH ALOFT ENTERING WESTERN NORTH DAKOTA. A 300MB
80KT JET STRETCHES FROM CENTRAL NORTH DAKOTA INTO MANITOBA. THE
RIGHT ENTRANCE REGION IS PROMOTING UPWARD VERTICAL MOTION OVER
CENTRAL NORTH DAKOTA PER IR SATELLITE IMAGERY WITH SCT TO BKN HIGH
CLOUDS AS TOTAL MOISTURE COLUMN REMAINS RELATIVELY DRY. THIS JET
EXITS THE AREA THIS MORNING WITH SINKING MOTION RETURNING/MOSTLY
SUNNY SKIES BEHIND THE WAVE AND IN RESPONSE TO THE APPROACH OF A
TRANSITORY RIDGE. THE NEXT UPPER LOW/TROUGH WAS SEEN MOVING INTO
THE WESTERN WASHINGTON/OREGON COAST. MODELS IN FAIRLY GOOD
AGREEMENT IN MOVING THE ENTIRE WAVE COMPLEX SOUTHEAST. CONCERNS
IN THE SHORT TERM WILL REVOLVE AROUND PRECIPITATION CHANCES MAINLY
OVER THE FAR SOUTHWEST AND FAR SOUTHEAST CWA TONIGHT THROUGH
TUESDAY. THEREAFTER...THE NEXT CONCERN WILL BE AN ALBERTA CLIPPER
PLOWING THROUGH TUESDAY NIGHT. OVERALL TEMPERATURES WILL TREND
COLDER TODAY THEN REMAIN FAIRLY FLAT UNTIL TUESDAY NIGHT WHEN
STRONG COLD AIR ADVECTION TAKES CONTROL.

THE LATEST FOG/STRATUS IMAGERY LOOP SHOWS AN AREA OF LOW CLOUDS
ACROSS NORTHWEST NORTH DAKOTA MOVING EAST WITH TIME. THE NAM
925-850MB MOISTURE VERIFIES FAIRLY WELL WHEN OVERLAID ON THE
CURRENT IMAGERY. EXPECT THE BULK OF LOW CLOUDS TO REMAIN OVER
NORTHERN NORTH DAKOTA NOW THROUGH 15Z FOLLOWING THE 925MB-850MB
WINDS. ELSEWHERE...CURRENT HIGH LEVEL CLOUDS ARE MOSTLY OBSCURING
STRATUS FROM BEING SEEN ON THE FOG/STRATUS IMAGERY...HOWEVER
THERE ARE SOME HOLES AND SIGNS OF PATCHY LOW CLOUDS DEVELOPING IN
OUR SOUTH CENTRAL ZONES. THIS IN LINE WITH THE CURRENT RELATIVE
HUMIDITY TIME/HEIGHT CROSS SECTIONS. WILL PAINT SOME PATCHY CLOUDS
INTO THE SKY GRIDS THIS MORNING BUT OVERALL EXPECT A QUICK RETURN
TO MOSTLY SUNNY SKIES. AFTERNOON HIGH TEMPERATURES WILL BE ABOUT
10 DEGREES COOLER THAN SATURDAY`S HIGHS.

FOR TONIGHT AND MONDAY...THE AFOREMENTIONED PACIFIC NORTHWEST
LOW/TROUGH WILL DIVE SOUTHEAST AND GRAZE OUR SOUTHWEST ZONES.
MAINTAINED A SLIGHT CHC SNOW TONIGHT INTO MONDAY MORNING AS THIS
AREA IS CLOSEST TO THE UPPER LOW. A SURFACE LOW SPINS UP ACROSS
NEBRASKA AND SOUTH DAKOTA MONDAY WITH AN INVERTED TROUGH JUST
REACHING INTO SOUTHERN NORTH DAKOTA. THE GFS BRINGS PRECIPITATION
UP THROUGH THIS AREA WHILE THE ECMWF IS FURTHER EAST AND SOUTH. A
SLIGHT CHC TO CHC OF RAIN/SNOW IS POSSIBLE OVER OUR FAR SOUTHEAST
ZONES GIVEN THE UNCERTAINTY BETWEEN THE MODELS. WILL LOWER POPS
ELSEWHERE WITH MODELS IN GOOD AGREEMENT ON DRY CONDITIONS OTHER
THAN THE SOUTHWEST AND SOUTHEAST. THE ENTIRE SYSTEM PUSHES FURTHER
SOUTH TUESDAY MORNING WITH DRY WEATHER RESULTING THROUGH THE
DAYLIGHT HOURS.

FOR TUESDAY INTO TUESDAY NIGHT...AN ALBERTA CLIPPER SYSTEM APPROACHES
OUR NORTHWESTERN ZONES TUESDAY AFTERNOON WHICH SWINGS A COLD FRONT
THROUGH THE CWA TUESDAY EVENING...BETWEEN 00Z AND 06Z WEDS. BRISK
NORTHWEST WINDS AND COLD AIR ADVECTION TAKE CONTROL AFTER MIDNIGHT.
PRECIPITATION WILL BE LIMITED GIVEN MOISTURE SOURCE OF SYSTEM AND
LACK OF ANY SIGNIFICANT MOISTURE ADVECTION INTO NORTH DAKOTA. SOME
FLURRIES OR A SLIGHT CHANCE OF SNOW AT BEST TUESDAY NIGHT OVER FAR
EAST CENTRAL NORTH DAKOTA WITH OUR WESTERN ZONES REMAINING DRY BUT
BLUSTERY.

.LONG TERM...WEDNESDAY THROUGH SUNDAY
MEDIUM RANGE MODELS IN FAIR AGREEMENT AT BEGINNING OF EXTENDED WITH
DIFFERENCES DEVELOPING BY LATE IN THE PERIOD. WILL GENERALLY USE
ECMWF FOR THE GRIDS WITH THIS MODEL MORE CONSISTENT DURING THE PAST
WEEK.

DOUBLE LOWS OVER NORTHERN PLAINS TO GREAT LAKES AND MIDWEST AT
BEGINNING OF PERIOD. SURFACE LOW INTO WISCONSIN AND ILLINOIS WITH
FAIRLY GOOD CAA OVER THE NORTHERN PLAINS. COOLER DAY THAN PAST WEEK.
MID LEVEL LOWS MERGE OVER MIDWEST ON THANKSGIVING WITH CAA
CONTINUING THOUGH GENERALLY DRY OVER THE WESTERN PLAINS AS RIDGING
DEVELOPS FROM NORTHERN ROCKIES TO CANADIAN PRAIRIE PROVINCES. SLIGHT
CYCLONIC FLOW MAY PRODUCING A LITTLE LIGHT PRECIPITATION MID WEEK
OVER FAR EASTERN PORTIONS OF FORECAST AREA.

BY BEGINNING OF NEXT WEEKEND RIDGING FULLY OVER NORTHERN PLAINS AND
WAA BEGINNING AHEAD OF NEXT ALBERTA CLIPPER WHICH DEVELOPS OVER
SASKATCHEWAN AND ALBERTA SATURDAY AND SUNDAY. GFS BRINGS COLDEST AIR
OF SEASON TO NORTHERN PLAINS ON SUNDAY AND SUNDAY NIGHT THOUGH GFS
IS TRENDING WARMER AND CLOSER TO ECMWF AND WILL FOLLOW ECMWF.

&&

.AVIATION...
GUSTY WINDS AHEAD OF SECONDARY FRONT MOVING THROUGH WESTERN NORTH
DAKOTA AND SMALL PATCH OF NEAR MVFR CLOUDS OVER NORTHERN TAF SITES
ONLY CONCERNS WITH THIS AVIATION PACKAGE.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$


KS/HW

000
FXUS63 KFGF 220329
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
929 PM CST SAT NOV 21 2009

.DISCUSSION...
MAIN ISSUE FOR TONIGHT CONTINUES TO BE TEMPERATURES. WINDS ON
EASTERN PORTION OF CWA HAVE YET TO DECOUPLE...AND STILL SEE GUSTS
INTO THE 20 TO 25 MPH RANGE. CONSEQUENTLY TEMPS IN THE EASTERN
VALLEY REMAIN IN THE UPPER 40S. WILL ADJUST TEMP GRID AND
INCREASE TEMPS IN THE EASTERN VALLEY. ALSO UPDATING WINDS IN THE
WEST...WHICH HAVE DECOUPLED AND ARE NOW RIGHT AROUND 10 MPH. RUC
HAS A DECENT HANDLE ON WINDS...AND HAVE UPDATED WIND GRIDS WITH RUC
GUIDANCE THROUGH 12Z.

&&

.AVIATION...
VFR CONDS WEST OF BJI. SMALL AREA OF VFR CIGS AROUND 3K FEET HAVE
ADVECTED INTO THE BJI AREA...AND WILL LIKELY NEED TO SEND
AMENDMENT TO BJI TAF OUT SHORTLY. DO NOT EXPECT TO SEE CIGS LOWER
THAN 2500 FT AND SHOULD MAINLY BE ALONG AND EAST OF A BJI TO PKD
LINE. MVFR SHOULD DISSIPATE AFTER SFC TROUGH PUSHES THROUGH LATER
IN THE NIGHT.

&&

.PREV DISCUSSION... /ISSUED 252 PM CST SAT NOV 21 2009/

SHORT TERM...
THE MAIN FORECAST CHALLENGE IS PCPN. WHEN LOOKING AT THE LATEST
SURFACE ANALYSIS...AN AREA OF LOW PRESSURE IS CENTERED IN E
SASK...WITH A TROF EXTENDING ALONG THROUGH W ND. WHEN LOOKING AT
THE MODELS...THEY REMAIN SIMILAR INITIALLY...THEN DIVERGE WITH THE
ECMWF THE SLOWEST AND THE GFS THE MOST PROGRESSIVE. THUS...ENDED
UP USING A MODEL BLEND FOR POP FORECAST AND PRETTY MUCH STUCK WITH
THE ADJMAV FOR TEMPS.

THE WINDY CONDITIONS WILL DIMINISH WITH LOSS OF INSOLATION THIS
EVENING AS THE TROF PASSES AND WINDS TURN TO THE SW-W BY SUN
MORNING. OTHERWISE...ONLY A FEW HIGH CLOUDS ARE ANTICIPATED WITH
THIS TROF. THIS SURFACE TROF IS EXPECTED TO BE E OF THE AREA BY SUN
AFTERNOON AS A 500MB TROF APPROACHES...KEEPING THE BEST LIFT AND
MOISTURE E OF THE AREA...AS WELL AS THE POTENTIAL FOR ANY PCPN.

ON SUN NIGHT...A SURFACE LOW DEVELOPS IN THE PLAINS AS A 500MB LOW
STARTS MOVING OUT OF THE ROCKIES. MODELS ARE STILL HAVING TROUBLE
WITH THE TIMING AND TRACK OF THIS SYSTEM. THE OVERALL THEME FOR
FORECASTING FOR THIS STORM IS THAT THE ATMOSPHERIC PROFILES STAY
WARMER LONGER THAN PREVIOUSLY THOUGHT...SO NOW SHOULD SEE MORE
RAIN FOR THE AREAS THAT DO GET PCPN THAN SNOW. ALSO...THE AREAS
WITH THE HIGHEST POTENTIAL FOR SEEING ANY PCPN AREA SE ND...WC AND
NW MN. THUS...STARTED CUTTING BACK AND REMOVING POPS FOR PARTS OF
NE ND FOR SUN NIGHT INTO TUE.

LONG TERM...(TUE NIGHT TO SAT)
ALTHOUGH MODEL RUN TO RUN CONSISTENCY HAS BEEN RATHER POOR THE
PAST SEVERAL DAYS...IT APPEARS THE 12 UTC GFS/DGEX/ECMWF HAVE
FINALLY LOCKED ONTO THE POSITION OF AN UPPER LOW TO IMPACT THE
UPPER MIDWEST MID-WEEK. AT 00 UTC WED...ALL THREE MODELS SHOW
UPPER LOW TO BE CENTERED ACROSS E IOWA...WEAKENING THEREAFTER AS
IT MOVES NE INTO THE GREAT LAKES REGION.

BEHIND THIS DEPARTING SYSTEM...ANOTHER PIECE OF SHORT-WAVE ENERGY
DROPS S ACROSS THE DAKOTAS TUE NIGHT AND WED. GIVEN NW FLOW
ALOFT...MOISTURE WILL BE LESS WITH THIS SECOND WAVE...SO KEPT POPS
AT 20-30 PERCENT FOR NOW. HOWEVER...ANY PCPN THAT DOES FALL DURING
THIS TIME LOOKS TO BE MOSTLY SNOW AS 850 HPA TEMPERATURES DROP TO
-6 TO -8 C. DAYTIME HIGHS WED AND THANKSGIVING DAY WILL BE IN THE
LOW TO MID 30S... CLOSER TO SEASONAL NORMALS...BUT NOTICEABLY
COOLER COMPARED TO OUR RECENT WARM STREAK.

THE LATTER HALF OF THE WEEK INTO NEXT WEEKEND LOOKS DRY...BUT COOL
AS AN UPPER RIDGE/SURFACE HIGH PRESSURE MOVE INTO THE REGION.

AVIATION...
PRIMARY AVIATION IMPACT CONCERNS STRONG S WINDS WITH GUSTS TO 30
KTS THIS AFTERNOON AND EARLY EVENING. AS SUN SETS...SURFACE SHOULD
DECOUPLE SOMEWHAT FROM MUCH STRONGER WINDS ALOFT (40 TO 50 KTS AT
2000 TO 3000 FT)...BUT DO NOT EXPECT SURFACE FLOW TO BECOME CALM.
OVERALL...WINDS WILL DECREASE AND GRADUALLY SHIFT TO THE SW OVERNIGHT
WITH PASSAGE OF A WEAK BOUNDARY. EXPECT PERIODS OF CIRRUS AT ALL
AIR FIELDS...ALTHOUGH SOME LOW VFR CEILINGS MAY APPROACH KBJI BY
MIDNIGHT. DID NOT INCLUDE THIS IN CURRENT TAF...BUT WILL NEED TO
WATCH FOR THIS AS THE EVENING PROGRESSES.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
SPEICHER

000
FXUS63 KFGF 212052
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
252 PM CST SAT NOV 21 2009

.SHORT TERM...
THE MAIN FORECAST CHALLENGE IS PCPN. WHEN LOOKING AT THE LATEST
SURFACE ANALYSIS...AN AREA OF LOW PRESSURE IS CENTERED IN E
SASK...WITH A TROF EXTENDING ALONG THROUGH W ND. WHEN LOOKING AT
THE MODELS...THEY REMAIN SIMILAR INITIALLY...THEN DIVERGE WITH THE
ECMWF THE SLOWEST AND THE GFS THE MOST PROGRESSIVE. THUS...ENDED
UP USING A MODEL BLEND FOR POP FORECAST AND PRETTY MUCH STUCK WITH
THE ADJMAV FOR TEMPS.

THE WINDY CONDITIONS WILL DIMINISH WITH LOSS OF INSOLATION THIS
EVENING AS THE TROF PASSES AND WINDS TURN TO THE SW-W BY SUN
MORNING. OTHERWISE...ONLY A FEW HIGH CLOUDS ARE ANTICIPATED WITH
THIS TROF. THIS SURFACE TROF IS EXPECTED TO BE E OF THE AREA BY SUN
AFTERNOON AS A 500MB TROF APPROACHES...KEEPING THE BEST LIFT AND
MOISTURE E OF THE AREA...AS WELL AS THE POTENTIAL FOR ANY PCPN.

ON SUN NIGHT...A SURFACE LOW DEVELOPS IN THE PLAINS AS A 500MB LOW
STARTS MOVING OUT OF THE ROCKIES. MODELS ARE STILL HAVING TROUBLE
WITH THE TIMING AND TRACK OF THIS SYSTEM. THE OVERALL THEME FOR
FORECASTING FOR THIS STORM IS THAT THE ATMOSPHERIC PROFILES STAY
WARMER LONGER THAN PREVIOUSLY THOUGHT...SO NOW SHOULD SEE MORE
RAIN FOR THE AREAS THAT DO GET PCPN THAN SNOW. ALSO...THE AREAS
WITH THE HIGHEST POTENTIAL FOR SEEING ANY PCPN AREA SE ND...WC AND
NW MN. THUS...STARTED CUTTING BACK AND REMOVING POPS FOR PARTS OF
NE ND FOR SUN NIGHT INTO TUE.

.LONG TERM...(TUE NIGHT TO SAT)
ALTHOUGH MODEL RUN TO RUN CONSISTENCY HAS BEEN RATHER POOR THE
PAST SEVERAL DAYS...IT APPEARS THE 12 UTC GFS/DGEX/ECMWF HAVE
FINALLY LOCKED ONTO THE POSITION OF AN UPPER LOW TO IMPACT THE
UPPER MIDWEST MID-WEEK. AT 00 UTC WED...ALL THREE MODELS SHOW
UPPER LOW TO BE CENTERED ACROSS E IOWA...WEAKENING THEREAFTER AS
IT MOVES NE INTO THE GREAT LAKES REGION.

BEHIND THIS DEPARTING SYSTEM...ANOTHER PIECE OF SHORT-WAVE ENERGY
DROPS S ACROSS THE DAKOTAS TUE NIGHT AND WED. GIVEN NW FLOW
ALOFT...MOISTURE WILL BE LESS WITH THIS SECOND WAVE...SO KEPT POPS
AT 20-30 PERCENT FOR NOW. HOWEVER...ANY PCPN THAT DOES FALL DURING
THIS TIME LOOKS TO BE MOSTLY SNOW AS 850 HPA TEMPERATURES DROP TO
-6 TO -8 C. DAYTIME HIGHS WED AND THANKSGIVING DAY WILL BE IN THE
LOW TO MID 30S... CLOSER TO SEASONAL NORMALS...BUT NOTICEABLY
COOLER COMPARED TO OUR RECENT WARM STREAK.

THE LATTER HALF OF THE WEEK INTO NEXT WEEKEND LOOKS DRY...BUT COOL
AS AN UPPER RIDGE/SURFACE HIGH PRESSURE MOVE INTO THE REGION.

&&

.AVIATION...
PRIMARY AVIATION IMPACT CONCERNS STRONG S WINDS WITH GUSTS TO 30
KTS THIS AFTERNOON AND EARLY EVENING. AS SUN SETS...SURFACE SHOULD
DECOUPLE SOMEWHAT FROM MUCH STRONGER WINDS ALOFT (40 TO 50 KTS AT
2000 TO 3000 FT)...BUT DO NOT EXPECT SURFACE FLOW TO BECOME CALM.
OVERALL...WINDS WILL DECREASE AND GRADUALLY SHIFT TO THE SW OVERNIGHT
WITH PASSAGE OF A WEAK BOUNDARY. EXPECT PERIODS OF CIRRUS AT ALL
AIR FIELDS...ALTHOUGH SOME LOW VFR CEILINGS MAY APPROACH KBJI BY
MIDNIGHT. DID NOT INCLUDE THIS IN CURRENT TAF...BUT WILL NEED TO
WATCH FOR THIS AS THE EVENING PROGRESSES.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
NG/ROGERS

000
FXUS63 KBIS 212040
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
240 PM CST SAT NOV 21 2009

.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...

MODELS START OUT IN GOOD AGREEMENT BUT SUBTLE DIFFERENCES BEGIN
TO APPEAR BY SUNDAY NIGHT LEADING TO REDUCED FORECAST CONFIDENCE.
THE BIGGEST FORECAST CONCERNS ARE CHANCES OF PRECIPITATION SUNDAY
NIGHT THROUGH TUESDAY NIGHT.

CURRENTLY...THERE IS A SURFACE LOW MOVING THROUGH EASTERN
SASKATCHEWAN TOWARDS LAKE WINNIPEG IN MANITOBA. THE ASSOCIATED
COLD FRONT HAS PUSHED INTO WESTERN NORTH DAKOTA THROUGH DICKINSON
AND WILL CONTINUE MOVING EAST TONIGHT. A STRONG PRESSURE GRADIENT
AND MIXING OF THE LOWER ATMOSPHERE BEHIND THE COLD FRONT HAVE
CAUSED STRONG WEST-NORTHWESTERLY WINDS. AHEAD OF THE FRONT...THE
STRONGEST PRESSURE GRADIENT HAS ALREADY PUSHED INTO EASTERN NORTH
DAKOTA. THE COLD FRONT IS FORECAST TO BE ALONG A LINE FROM MINOT
TO BISMARCK BY 00 UTC SUNDAY AND NEAR JAMESTOWN BY 06 UTC...AND
THE ATMOSPHERE SHOULD DECOUPLE THIS EVENING AND END THE GUSTY
WINDS.

AN UPPER LEVEL TROUGH ASSOCIATED WITH THE AFOREMENTIONED LOW
PRESSURE SYSTEM MOVES THROUGH NORTH DAKOTA TONIGHT AND SHORT WAVE
RIDGING MOVES THROUGH THE REGION IN ITS WAKE. RIDGING IS SHORT-LIVED
AS ANOTHER DISTURBANCE APPROACHES FOR SUNDAY NIGHT INTO MONDAY.
THE 12 UTC GFS AND ECMWF BEGIN TO DISAGREE AT THIS POINT WITH THE
PATH OF THE TROUGH. THE ECMWF DROPS THIS TROUGH FARTHER TO THE
SOUTH INTO NEBRASKA AND PAINTS PRECIPITATION ACROSS MAINLY
SOUTHEASTERN NORTH DAKOTA TONIGHT INTO MONDAY MORNING. THE GFS
MOVES THE UPPER LEVEL LOW THROUGH SOUTH DAKOTA AND SHOWS SOME
LIGHT PRECIPITATION ACROSS WESTERN AND CENTRAL NORTH DAKOTA. WITH
MODELS SPLIT ON THE PATH OF THIS SYSTEM...GRIDDED FORECASTS HAVE
ONLY A SLIGHT CHANCE OF PRECIPITATION FOR SUNDAY NIGHT. THE
EXCEPTION IS IN FAR SOUTHWEST NORTH DAKOTA WHERE PRECIPITATION
CHANCES ARE SLIGHTLY HIGHER DUE TO MODEL/ENSEMBLE OVERLAP THERE.
GUIDANCE SUPPORTS MORE DISTURBANCES MOVING THROUGH THE NORTHERN
PLAINS THROUGH TUESDAY NIGHT...JUSTIFYING CHANCES OF
PRECIPITATION AND SLIGHTLY COOLER TEMPERATURES. THAT
SAID...TEMPERATURES SHOULD REMAIN ABOVE AVERAGE THROUGH MOST OF
THE PERIOD.

.LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT...

THE LONG TERM BEGINS WEDNESDAY WITH THE MODELS DEPICTING A LOW OVER
THE MID-MISSISSIPPI VALLEY/GREAT LAKES AREA AND DRY NORTHWESTERLY
FLOW OVER NORTH DAKOTA...WITH RIDGING TO THE WEST. THE GFS KEEPS
THIS UPPER LEVEL RIDGE AXIS TO OUR WEST UNTIL FRIDAY...THEN BRINGS
THE NEXT UPPER LEVEL SHORTWAVE ACROSS SOUTHERN SASKATCHEWAN AND
MANITOBA. THE EUROPEAN MODEL IS FASTER WITH THE UPPER LEVEL RIDGE
AXIS...BUT THEN DEVELOPS THE NEXT SHORTWAVE FARTHER SOUTH NEAR
COLORADO AND THE 4 CORNERS AREA BY SATURDAY. THUS WILL KEEP THE
FORECAST DRY THROUGHOUT THE EXTENDED PERIOD.

THE UPPER LEVEL RIDGING ON THURSDAY - THANKSGIVING DAY - WILL BRING
MILD WEATHER TO NORTH DAKOTA. EXPECTING AVERAGE TO ABOVE AVERAGE
TEMPERATURES...WITH MORNING LOWS IN THE UPPER TEENS TO LOWER 20S AND
HIGHS FROM THE MID 30S EAST TO UPPER 40S SOUTHWEST. IN FACT...MOST
OF THE EXTENDED SHOULD SEE HIGHS 35 TO 45 FOR MOST DAYS AND LOWS IN
THE TEENS AND 20S. AVERAGES FOR THIS TIME OF YEAR ARE GENERALLY
HIGHS IN THE LOWER 30S AND LOWS IN THE TEENS.

&&

.AVIATION...

A SURFACE LOW OVER SASKATCHEWAN IS FORECAST TO MOVE EASTWARD INTO
MANITOBA TONIGHT. A TROUGH EXTENDING SOUTHWARD FROM THE LOW WILL
CONTINUE PUSHING EASTWARD ACROSS THE DAKOTAS AND INTO MINNESOTA BY
AROUND 06Z. EXPECT TROUGH TO MOVE THROUGH KBIS AND KMOT BY AROUND
00Z AND KJMS AFT 03Z. GUSTY SOUTH WINDS AHEAD OF THE TROUGH...WITH
GUSTS TO 30KTS AT KJMS...AND GUSTY WEST WINDS BEHIND IT THROUGH
02Z...THEN WIND SPEEDS DECREASING. EXPECT MAINLY HIGH CIRRUS CLOUDS
WITH SCATTERED MID CLOUDS 10000-15000 FT. SOME SCATTERED CLOUDS
3000-5000 FT MOVING INTO THE STATE AFT 10Z. LIGHTER SOUTHWEST WINDS
ON SUNDAY.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS/SHORT TERM...DC/SCHECK
AVIATION...DC/JV
LONG TERM...JV

000
FXUS63 KFGF 211640 AAA
AFDFGF

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GRAND FORKS ND
1039 AM CST SAT NOV 21 2009

.DISCUSSION...
THE MAIN FORECAST CHALLENGES ARE TEMPS AND WINDS. WHEN LOOKING AT
THE LATEST SURFACE ANALYSIS...AN AREA OF LOW PRESSURE IS CENTERED IN
SASK...WITH A TROF EXTENDING ALONG THE MT/ND LINE. WHEN LOOKING AT
THE MODELS...THEY REMAIN SIMILAR IN KEEPING E ND...NW AND WC MN IN S
FLOW TODAY WITH A TIGHTENING SURFACE PRESSURE GRADIENT CREATING
WINDY CONDITIONS. THUS...PRETTY MUCH KEPT FORECAST CONTINUITY FOR
THIS UPDATE.

TEMPS NOT WARMING AS QUICKLY AS EARLIER EXPECTED...ESPECIALLY IN THE
DVL AREA...SO DID NEED TO MAKE A SLIGHT DOWNWARD ADJUSTMENT FOR
TODAY`S MAX IN SOME AREAS. WITH WINDS STILL ANTICIPATED TO MIX TO
ABOUT 925 MB...WHICH COULD RESULT IN GUSTS UP TO 40 MPH. HOWEVER...
SINCE THIS IS STILL BELOW ADVISORY CRITERIA AND WITH TEMPS NOT
WARMING AS FAST AS PREVIOUSLY EXPECTED...WILL HOLD OFF ON ISSUING
ANY WIND HEADLINES AT THIS TIME. REST OF FORECAST IN GOOD
SHAPE...WITH ONLY MINOR CHANGES NEEDED.

&&

.AVIATION...
VFR SKY AND VSBY TO CONTINUE TODAY WITH SE-S WINDS INCREASING BY
21Z WITH GUSTS TO AROUND 30 KTS POSSIBLE.

&&

.PREV DISCUSSION... /ISSUED 332 AM CST SAT NOV 21 2009/

SHORT TERM (SAT-MON)...MAIN CONCERN WILL BE WIND POTENTIAL TODAY
AND THEN PCPN CHANCES ON MON. TEMPERATURES WILL ALSO BE A
CHALLENGE. 00Z MODELS INITIALIZED WITH MINIMAL ERRORS. NAM IS
SLIGHTLY SLOWER AND MORE AMPLIFIED THAN OTHER GUIDANCE WITH THE
BOUNDARY TODAY...AND WILL LEAN AWAY FROM ITS SOLUTION. FOR LATER
IN THE PERIOD...MODELS (GEM...ECMWF...GFS...NAM) ARE IN BETTER
AGREEMENT BUT STILL ENOUGH DIFFERENCES TO KEEP THINGS UNCERTAIN.
WILL FOLLOW A BLEND.

TODAY...GFS SOUNDINGS INDICATE MIXING TO AROUND 850MB
POSSIBLE...WHILE NAM INDICATES AROUND 925MB. THE DEEPER MIXING
DEPTH OF THE GFS IS LIKELY DUE TO COOLING 850MB TEMPS THROUGH THE
AFTERNOON AS 850MB THERMAL RIDGE PROPAGATES TO THE E. THE SLOWER
NAM KEEPS THE 850MB THERMAL RIDGE OVER THE FA THROUGH MUCH OF THE
AFTERNOON...KEEPING THE INVERSION INTACT ABOVE 925MB. WITHOUT
COOLING AT 850MB...THINK THAT WITH A S/SE SFC WIND AND LATE NOV
SUN ANGLE THAT IT WILL BE HARD TO HEAT ENOUGH AT THE SFC TO MIX
MUCH ABOVE 925MB. IF THE PREFERRED QUICKER SOLUTION IS CORRECT AND
WE DO MIX TO 850MB...WINDS ALOFT BY LATE MORNING AND INTO THE
AFTERNOON HOURS WILL BE WEAKENING. SO...THE SLOWER SOLUTION WILL
NOT ALLOW MIXING TO THE VERY STRONG WINDS ALOFT...AND THE QUICKER
SOLUTION WILL ALLOW DEEPER MIXING BUT TO WEAKER WINDS ALOFT. STILL
WINDY TODAY...BUT SHOULD BE BELOW ADVISORY CRITERIA. THE ONLY
REASON TO WORRY AND HAVE SUCH A LONG DISCUSSION IS BECAUSE THE
850MB WINDS WILL BE AROUND 55 KTS AT 18Z (JUST THAT THE NAM HANGS
ON TO THESE STRONGER WINDS ALOFT THROUGH THE AFTERNOON). GIVEN
EITHER SOLUTION...MAX TEMPS IN THE LOW 50S A GOOD BET.

TONIGHT-SUN NIGHT...APPROACHING UPPER TROUGH WILL MOVE ACROSS THE
REGION. THIS FEATURE WILL LACK MOISTURE UNTIL THE FORCING IS E OF
THE FA. REMOVED THE 20 POPS ACROSS THE E FA FOR SUN. MIN TEMPS SUN
MORNING SHOULD BE WARMEST ACROSS THE E WHERE BEST SFC MOISTURE
RETURN AHEAD OF APPROACHING SYSTEM WILL BE. AIR MASS COOLS A BIT
COMPARED WITH SAT...BUT WESTERLY SFC FLOW SHOULD ALLOW TEMPS TO
RISE INTO THE MID-40S. LIGHTER WINDS SUN NIGHT SHOULD ALLOW TEMPS
TO FALL TO NEAR DEW POINTS VALUES (LOW-MID 20S). CLOUDS APPROACHING
FROM THE SOUTH COULD KEEP MIN TEMP VALUES IN THE 30S ACROSS THE
FAR S FA.

MON-MON NIGHT...FORMING 500MB LOW SOUTH OF THE FA WITH INVERTED
SFC TROUGH INTO THE FA SHOULD LEAD TO INCREASING PCPN CHANCES. AT
THIS TIME THINKING MOSTLY A RAIN THREAT GIVEN MODEL 925MB TEMPS.

LONG TERM (TUE-FRI)...MAIN CHALLENGE WILL BE HOW LONG CLOUDS AND
PCPN LINGERS ACROSS THE E FA AND THEN TEMPERATURES. MODELS COMING
INTO SOME AGREEMENT...BUT STILL ENOUGH DIFFERENCES TO KEEP
CONFIDENCE TOWARD THE LOW END. CURRENT FORECAST REASONABLE AND NO
CHANGES PLANNED.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
NG

000
FXUS63 KFGF 210932
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
332 AM CST SAT NOV 21 2009

.SHORT TERM (SAT-MON)...MAIN CONCERN WILL BE WIND POTENTIAL TODAY
AND THEN PRECIP CHANCES ON MONDAY. TEMPERATURES WILL ALSO BE A
CHALLENGE. 00Z MODELS INITIALIZED WITH MINIMAL ERRORS. NAM IS
SLIGHTLY SLOWER AND MORE AMPLIFIED THAN OTHER GUIDANCE WITH THE
BOUNDARY TODAY...AND WILL LEAN AWAY FROM ITS SOLUTION. FOR LATER
IN THE PERIOD...MODELS (GEM...ECMWF...GFS...NAM) ARE IN BETTER
AGREEMENT BUT STILL ENOUGH DIFFERENCES TO KEEP THINGS UNCERTAIN.
WILL FOLLOW A BLEND.

TODAY...GFS SOUNDINGS INDICATE MIXING TO AROUND 850MB
POSSIBLE...WHILE NAM INDICATES AROUND 925MB. THE DEEPER MIXING
DEPTH OF THE GFS IS LIKELY DUE TO COOLING 850MB TEMPS THROUGH THE
AFTERNOON AS 850MB THERMAL RIDGE PROPAGATES TO THE EAST. THE
SLOWER NAM KEEPS THE 850MB THERMAL RIDGE OVER THE FA THROUGH MUCH
OF THE AFTERNOON...KEEPING THE INVERSION INTACT ABOVE 925MB.
WITHOUT COOLING AT 850MB...THINK THAT WITH A SOUTH/SOUTHEAST SFC
WIND AND LATE NOVEMBER SUN ANGLE THAT IT WILL BE HARD TO HEAT
ENOUGH AT THE SFC TO MIX MUCH ABOVE 925MB. IF THE PREFERRED
QUICKER SOLUTION IS CORRECT AND WE DO MIX TO 850MB...WINDS ALOFT
BY LATE MORNING AND INTO THE AFTERNOON HOURS WILL BE WEAKENING.
SO...THE SLOWER SOLUTION WILL NOT ALLOW MIXING TO THE VERY STRONG
WINDS ALOFT...AND THE QUICKER SOLUTION WILL ALLOW DEEPER MIXING
BUT TO WEAKER WINDS ALOFT. STILL WINDY TODAY...BUT SHOULD BE
BELOW ADVISORY CRITERIA. THE ONLY REASON TO WORRY AND HAVE SUCH A
LONG DISCUSSION IS BECAUSE THE 850MB WINDS WILL BE AROUND 55KNTS
AT 18Z (JUST THAT THE NAM HANGS ON TO THESE STRONGER WINDS ALOFT
THROUGH THE AFTERNOON). GIVEN EITHER SOLUTION...MAX TEMPS IN THE
LOW 50S A GOOD BET.

TONIGHT-SUN NIGHT...APPROACHING UPPER TROUGH WILL MOVE ACROSS THE
REGION. THIS FEATURE WILL LACK MOISTURE UNTIL THE FORCING IS EAST
OF THE FA. REMOVED THE 20 POPS ACROSS THE E FA FOR SUN. MIN TEMPS
SUN MORNING SHOULD BE WARMEST ACROSS THE EAST WHERE BEST SFC
MOISTURE RETURN AHEAD OF APPROACHING SYSTEM WILL BE. AIRMASS COOLS
A BIT COMPARED WITH SAT...BUT WESTERLY SFC FLOW SHOULD ALLOW TEMPS
TO RISE INTO THE MID-40S. LIGHTER WINDS SUN NIGHT SHOULD ALLOW
TEMPS TO FALL TO NEAR DEW POINTS VALUES (LOW-MID 20S). CLOUDS
APPROACHING FROM THE SOUTH COULD KEEP MIN TEMP VALUES IN THE 30S
ACROSS THE FAR SOUTHERN FA.

MON-MON NIGHT...FORMING 500MB LOW SOUTH OF THE FA WITH INVERTED
SFC TROUGH INTO THE FA SHOULD LEAD TO INCREASING PRECIP CHANCES.
AT THIS TIME THINKING MOSTLY A RAIN THREAT GIVEN MODEL 925MB
TEMPS.

.LONG TERM (TUE-FRI)...MAIN CHALLENGE WILL BE HOW LONG CLOUDS AND
PRECIP LINGERS ACROSS THE EASTERN FA AND THEN TEMPERATURES. MODELS
COMING INTO SOME AGREEMENT...BUT STILL ENOUGH DIFFERENCES TO KEEP
CONFIDENCE TOWARD THE LOW END. CURRENT FORECAST REASONABLE AND NO
CHANGES PLANNED.

&&

.AVIATION...SOUTHERLY WINDS WILL INCREASE TODAY WITH GUSTS FROM
30-35KT POSSIBLE AT ALL SITES. VFR CONDITIONS ARE EXPECTED WITH
JUST SOME VERY HIGH CIRRUS AT TIMES.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
TG

000
FXUS63 KBIS 210853
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
250 AM CST SAT NOV 21 2009

.SHORT TERM...TODAY THROUGH MONDAY NIGHT...
THE LATEST WATER VAPOR IMAGERY SHOWS OUR FIRST IN A SERIES OF
SHORTWAVE TROUGHS SLIDING INTO IDAHO AND THE GREAT BASIN REGION.
DESPITE A 300MB 80KT JET AND DECENT OMEGA/UPWARD VERTICAL MOTION
IN THE RIGHT ENTRANCE REGION MOVING THROUGH NORTH DAKOTA TODAY...THE
OVERALL COLUMN REMAINS RELATIVELY DRY RESULTING IN A SCT CIRRUS
SHIELD TO THIN BKN AT TIMES. THE LATEST MSAS SHOWS A SURFACE COLD
FRONT NOW MOVING THROUGH WESTERN MONTANA AND EASTERN IDAHO. 3HR
PRESSURE FALLS OF 3MB TO 4MB WERE OBSERVED OVER WESTERN AND
SOUTHWESTERN NORTH DAKOTA INDICATIVE OF ONGOING WARM AIR ADVECTION.
THE WARM AIR ADVECTION WILL COME TO A HALT ACROSS WESTERN NORTH
DAKOTA AROUND SUNRISE AND ACROSS CENTRAL NORTH DAKOTA DURING THE
AFTERNOON. USING THE 1000-500MB THICKNESS PACKING FOR FRONTAL
PASSAGE/FROPA PLACEMENT AND TIMING...MODELS ARE IN BETTER AGREEMENT
WITH FRONTAL PASSAGE AND ONSET OF COLD AIR ADVECTION. SHOULD SEE
THIS OCCUR ACROSS THE WEST BETWEEN 15Z-18Z WEST
(KISN/KDIK)...21Z-00Z CENTRAL (KMOT/KBIS)...AND AROUND 06Z FAR
EASTERN COUNTIES WHICH INCLUDES KJMS. FULLY EXPECT A CONTINUED DRY
FRONTAL PASSAGE FORECAST AND HENCE MOSTLY SUNNY TO PARTLY CLOUDY
SKIES TODAY. STRONG SOUTHERLY WINDS OUT AHEAD OF THE FRONT WITH
MIXING TO AROUND 900MB OVER OUR FAR EASTERN ZONES FROM JAMESTOWN
SOUTH WILL YIELD WINDS BETWEEN 25 AND 35 MPH. CONTEMPLATED A WIND
ADVISORY BUT AFTER COLLABORATING WITH SURROUNDING OFFICES DECIDED TO
HIGHLIGHT THE GUSTY WINDS IN THE ZONES AND HWO. THE DAY SHIFT CAN
ISSUE A NOWCAST OR TWO IF NEEDED THIS AFTERNOON. AFTERNOON HIGHS
WILL BE MAXIMIZED ALONG AND JUST AHEAD OF THE FRONT TODAY WHICH
PLACES THE WARMEST AIR FROM AROUND BISMARCK SOUTH AND EAST. COOLER
FURTHER WEST.

TONIGHT AND SUNDAY...THE UPPER TROUGH WILL SLIDE THROUGH LATE
TONIGHT INTO SUNDAY MORNING FOLLOWED BY A TRANSITORY SHORTWAVE
RIDGE SUNDAY AFTERNOON. OVERALL AFTERNOON HIGH TEMPERATURES SUNDAY
WILL BE AROUND 8 TO 10 DEGREES COOLER THAN TODAY. CONTINUED DRY
TONIGHT AND SUNDAY.

SUNDAY NIGHT THROUGH MONDAY NIGHT...ANOTHER UPPER TROUGH WILL AFFECT
NORTH DAKOTA. THE GFS AND CANADIAN GEMGLB ARE IN CLOSE AGREEMENT
WITH THE TRACK OF THE LOW. THIS SOLUTION IS FURTHEST NORTH AND HAS
THE HIGHEST IMPACT FOR OUR CWA WITH AT LEAST A SLIGHT CHANCE OF
SNOW AND RAIN. THE NAM AND ECMWF DIG THE LOW FURTHER SOUTH AND
HENCE REMOVES THE PRECIPITATION THREAT...WITH THE EXCEPTION OF OUR
FAR SOUTHEASTERN COUNTIES. DECIDED TO MAKE LITTLE OR NO CHANGE TO
ONGOING POP/WEATHER GRIDS SUNDAY NIGHT THROUGH MONDAY NIGHT SINCE
CURRENT DATA IS NO MORE CONCLUSIVE THAN LAST COUPLE OF MODEL RUNS.
WHICHEVER MODEL IS CORRECT...ALL CONCUR ON A COLDER REGIME...AS
THE LOW MOVES SOUTH OF NORTH DAKOTA LATE MONDAY AND MONDAY NIGHT.
HIGH TEMPERATURES ON MONDAY WILL RANGE FROM THE UPPER 30S TO
AROUND 40 WHICH IS STILL ABOVE AVERAGE FOR THIS TIME OF YEAR.

.LONG TERM...TUESDAY THROUGH SATURDAY
SOME DIFFERENCES IN MEDIUM RANGE MODELS ESPECIALY AT END OF AND PAST
EXTENDED GRID PERIODS. AT BEGINNING OF EXTENDED GFS AND GEM SLIGHTLY
MORE PROGRESSIVE THAN ECMWF BUT MAJORITY OF MODELS HAVE QPF EAST OF
FORECAST AREA BY TUESDAY DAYTIME.

DIFFERENCES BEGIN TO APPEAR THURSDAY NIGHT AND FRIDAY AS CLOSED
DIGGS OVER GREAT LAKES AND RIDGING BUILDING IN NORTHERN ROCKIES AND
NORTHERN PLAINS. ECMWF LAGGS MORE ENERGY INTO A WESTERN CONUS TROUGH
WHILE GFS IS DEEP TROUGH REBUILDING GREAT LAKES REGION WITH MUCH
COLDER AIRMASS FARTHER WEST ON GFS. 511 DM THICKNESS ON GFS AND 524
ON ECMWF POISED JUST NORTH OF BORDER SOUTH OF LAKE WINNIPEG AT END
OF EXTENDED PERIODS. GENERALLY FOLLOWED GFS FOR TIMING BUT
AMELIORATED THE COLD TEMPS OF GFS WITH COMBO OF ECMWF AND GFS FOR
DAY 8.


&&

.AVIATION...
HIGH CLOUDS SPREADING FROM WEST TO EAST WILL BRING THIN BROKEN
CONDITIONS TO WESTERN AND CENTRAL NORTH DAKOTA. ONLY CONCERN WILL BE
STRENGTH OF WINDS OVER EASTERN TAF SITES WHERE GUSTS TO 35 MPH ARE
POSSIBLE THIS AFTERNOON.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

KS/HW