000
FXUS63 KIWX 222323
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
625 PM EST SUN NOV 22 2009

.AVIATION...
UPPER LEVEL DISTURBANCE MOVING UP TOWARD OHIO VALLEY THIS EVENING
SPREADING SOME THIN CIRRUS OVER THE AREA. GRADIENT TIGHTENING
SOMEWHAT AS SFC HIGH NOW OVER MAINE...BUT STRONG SFC BASED INVERSION
TO DEVELOP AGAIN TONIGHT AND SHOULD ALLOW FOR DECOUPLING TO KEEP
WINDS AOB 5KTS. THIN HIGH CLOUDS SHOULD NOT INHIBIT GOOD RADIATIONAL
COOLING AND SUBSEQUENT MVFR FOG AGAIN TONIGHT. OTHERWISE EXPECT VFR
CONDITIONS AT BOTH TAF SITES THIS PERIOD.

&&

.SHORT TERM...
ANOTHER BOUT OF FOG FOR MONDAY MORNING SIMILAR TO PREVIOUS NIGHTS
GIVING WAY TO FAIR CONDITIONS WITH INCREASING CLOUDS AS A
SHORTWAVE APPROACHING FROM THE GREAT PLAINS ACTS TO LIFT WEAKER
WAVE CURRENTLY OVER THE DEEP SOUTH ON A TRACK TO OUR EAST.
ALTHOUGH SREF HAS BACKED OFF POP PROBABILITIES FOR THE
SOUTHEASTERN COUNTIES WILL LEAVE THEM IN THE GRIDS FOR THIS
PACKAGE RATHER THAN RISK A FLIP FLOP AS HIGH PROBS REMAIN JUST
OUTSIDE THE CWA AND THE GFS CONTINUES TO SHOW WEAK ASCENT OVER THIS
AREA. BUMPED TEMPS A LITTLE CLOSER TO A MIX TO H92 IN THE WEST AS
NAM/GFS/SREF MOISTURE FIELDS SUPPORT SEEING SUN THROUGH 18Z.
MILDER LOWS MONDAY NIGHT AS MOISTURE/CLOUD COVER INCREASES AHEAD
OF AN ACTIVE PERIOD BEGINNING IN THE EARLY EXTENDED.

&&

.LONG TERM...
MED RANGE GUIDANCE CONTS IN DECENT AGREEMENT W/POTENT SW TROUGH OVR
WA STATE THIS AFTN DIGGING INTO THE CNTRL PLAINS TUE AND THEN
EJECTING NEWD INTO THE LAKES WED AHD OF RAPIDLY AMPLIFYING SECONDARY
DROPPING OUT OF CANADA AND PUTS MUCH OF THE PD IN A WET/COOL PATTN
THROUGH LT WEEK.

PREFERENCE LIES TWD DETAILS OF ECMWF W/A PREFERRED SLWR EWD
PROGRESSION DEEP CLOSED CYCLONE TUE/WED AND WILL BACK OFF PRECIP
ARRIVAL DURING THE DAY TUE. OTHERWISE PRIOR GRIDDED POPS STILL FIT
W/CURRENT EXPECTATIONS AND WILL AWAIT FOR MORE SOLIDIFIED MODEL
TIMING BFR BUMPING ANY MID WEEK PDS FURTHER. LL TEMP GUIDANCE STILL
FVRS MORE RAIN THEN SNOW W/WARM BNDRY LYR TEMPS...HWVR DEEP
SECONDARY THU MAY YIELD ENOUGH DIABATIC/ADIABATIC COOLING TO FOSTER
MORE SNOW THEN ADVERTISED ASSUMING SRN TRACK OF ECMWF VERIFIES.
OTHERWISE TEMPS FOR MOST OF THE PD AOB NORMAL AND QUITE WET/RAW
WED-FRI.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUD
LONG TERM...HOLSTEN
AVIATION...LOGSDON

000
FXUS63 KIND 222259
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
600 PM EST SUN NOV 22 2009

.AVIATION DISCUSSION...FOR THE 00Z TAFS
HIGH PRESSURE WILL CONTINUE TO BE THE MAIN WEATHER SYSTEM
CONTROLLING INDIANAS WEATHER. TAFS WILL START OUT VFR. SOME HIGH
LEVEL HIGH LEVEL MOISTURE WAS BEING PULLED UP THE BACKSIDE OF THIS
SYSTEM. THESE CLOUDS ALONG WITH CONTINUED DRYING OF SURFACE LAYERS
WILL LIMIT FOG DEVELOPMENT. VISIBILITIES WILL ONLY DECREASE TO MVFR
LEVELS AROUND SUNRISE. THEY WILL QUICKLY INCREASE TO VFR BY 15Z. THE
HIGH WILL CONTINUE TO MOVE SLOWLY TO THE EAST. MID AND HIGH CLOUDS
WILL CONTINUE TO MOVE INTO INDIANA ON THE BACKSIDE OF THE HIGH ON
MONDAY BUT CONDITIONS WILL REMAIN VFR.

&&

.DISCUSSION...

FORECAST FOCUS IS ON CHANCES FOR PRECIPITATION THIS WEEK.

AT 18Z HIGH PRESSURE CONTINUED TO PROVIDE WINDS FROM THE EAST ACROSS
THE FORECAST AREA THIS AFTERNOON. TEMPERATURES HAVE RESPONDED WELL
TO THE SUNSHINE ONCE AGAIN. MEANWHILE...A WEAKENING UPPER LOW WAS
NEAR SOUTHEASTERN TENNESSEE. RADAR MOSAIC SHOWED RAIN MOVING TOWARD
KENTUCKY FROM TENNESSEE.

SOME DISAGREEMENT IN THE MODELS BOTH IN MONDAY/S SYSTEM AS WELL AS
THE STRONGER ONE MID WEEK. FOR MONDAY...NAM IS DRIER THAN THE GFS
AND KEEPS RAIN WELL EAST OF THE AREA. GFS STILL SHOWS RAIN GETTING
INTO THE EASTERN PART OF THE AREA. GFS IS DOING BETTER CURRENTLY
WITH THE RAIN...SO WILL GO CLOSER TO ITS SOLUTION FOR MONDAY. BY MID
WEEK THE MODELS ARE SPLIT BETWEEN A FAST AND A SLOW SOLUTION. WITH
NO CLEAR FAVORITE...DECIDED TO SPLIT THE DIFFERENCE...ALSO TAKING
INTO ACCOUNT FORECAST CONTINUITY.

TONIGHT...CLOUDS WILL INCREASE MAINLY ACROSS THE SOUTHEASTERN HALF
OF THE AREA AS THE WEAKENING UPPPER SYSTEM MOVES NORTHEAST. THE WEAK
LIFT FROM THE SYSTEM LOOKS TO REMAIN SOUTH OF THE AREA DURING THE
NIGHT...PERHAPS GETTING INTO FAR SOUTHERN AREAS TOWARD 12Z. WITH
LITTLE LIFT AND LIMITED MOISTURE...CONTINUED THE DRY FORECAST
TONIGHT. GUIDANCE NUMBERS ARE SIMILAR FOR LOWS TONIGHT AND LOOK GOOD
GIVEN THE INCREASING CLOUDS.

THE UPPER SYSTEM PROVIDES A GLANCING BLOW TO THE AREA ON MONDAY.
WEAK ISENTROPIC LIFT ACROSS SOUTHEASTERN AREAS COULD BRING SOME
LIGHT RAIN...SO HAVE KEPT LOW POPS ACROSS THOSE AREAS. THICKER
CLOUDS ACROSS THE SOUTHEAST WILL KEEP TEMPERATURES COOLER THAN THE
NORTHWEST...AND MET GUIDANCE GENERALLY FOLLOWS THIS BETTER THAN THE
MAV...SO TRENDED TOWARD MET NUMBERS FOR HIGHS.

FIRST IN A SERIES OF UPPER LOWS WILL BEGIN TO BRING CHANCES FOR RAIN
TO THE AREA BEGINNING TUESDAY...MAINLY IN THE AFTERNOON. AS
MENTIONED EARLIER...THIS IS BETWEEN THE MODEL SOLUTIONS AND IS CLOSE
TO PREVIOUS FORECAST. THE UPPER LOW WILL THEN MOVE TO THE VICINITY
OF NORTHERN ILLINOIS BY 12Z WEDNESDAY. THUS WITH THE BETTER FORCING
ACROSS FAR NORTHERN AREAS...UPPED POPS TO LIKELY TUE NIGHT WITH
CHANCE POPS ELSEWHERE.

WHILE THERE WILL BE DRY PERIODS WEDNESDAY INTO WEDNESDAY
NIGHT...TIMING ISSUES PRECLUDE TIMING THE POPS...SO KEPT LOW POPS
THROUGH THAT PERIOD. MUCH COLDER AIR AND ANOTHER UPPER LOW ARRIVE
FOR THANKSGIVING AND THEIR ARRIVAL WILL KEEP CHANCE POPS IN THE
FORECAST. STILL LOOKS LIKE THERE WILL BE THE POTENTIAL FOR MIXED
PRECIPITATION...WITH THE THICKNESS OF THE WARM LAYER NEAR THE
SURFACE THE MAIN QUESTION. WITH SURFACE TEMPERATURES AROUND 40 AND
WET BULB TEMPERATURES NEAR FREEZING...ITS TOO TOUGH A CALL AT THIS
POINT IN TIME. WILL CONTINUE CHANCES FOR RAIN AND SNOW THANKSGIVING
AND THANKSGIVING NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...CS
AVIATION...SH

000
FXUS63 KIWX 222043
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
343 PM EST SUN NOV 22 2009

.SHORT TERM...
ANOTHER BOUT OF FOG FOR MONDAY MORNING SIMILAR TO PREVIOUS NIGHTS
GIVING WAY TO FAIR CONDITIONS WITH INCREASING CLOUDS AS A
SHORTWAVE APPROACHING FROM THE GREAT PLAINS ACTS TO LIFT WEAKER
WAVE CURRENTLY OVER THE DEEP SOUTH ON A TRACK TO OUR EAST.
ALTHOUGH SREF HAS BACKED OFF POP PROBABILITIES FOR THE
SOUTHEASTERN COUNTIES WILL LEAVE THEM IN THE GRIDS FOR THIS
PACKAGE RATHER THAN RISK A FLIP FLOP AS HIGH PROBS REMAIN JUST
OUTSIDE THE CWA AND THE GFS CONTINUES TO SHOW WEAK ASCENT OVER THIS
AREA. BUMPED TEMPS A LITTLE CLOSER TO A MIX TO H92 IN THE WEST AS
NAM/GFS/SREF MOISTURE FIELDS SUPPORT SEEING SUN THROUGH 18Z.
MILDER LOWS MONDAY NIGHT AS MOISTURE/CLOUD COVER INCREASES AHEAD
OF AN ACTIVE PERIOD BEGINNING IN THE EARLY EXTENDED.

&&

.LONG TERM...
MED RANGE GUIDANCE CONTS IN DECENT AGREEMENT W/POTENT SW TROUGH OVR
WA STATE THIS AFTN DIGGING INTO THE CNTRL PLAINS TUE AND THEN
EJECTING NEWD INTO THE LAKES WED AHD OF RAPIDLY AMPLIFYING SECONDARY
DROPPING OUT OF CANADA AND PUTS MUCH OF THE PD IN A WET/COOL PATTN
THROUGH LT WEEK.

PREFERENCE LIES TWD DETAILS OF ECMWF W/A PREFERRED SLWR EWD
PROGRESSION DEEP CLOSED CYCLONE TUE/WED AND WILL BACK OFF PRECIP
ARRIVAL DURING THE DAY TUE. OTHERWISE PRIOR GRIDDED POPS STILL FIT
W/CURRENT EXPECTATIONS AND WILL AWAIT FOR MORE SOLIDIFIED MODEL
TIMING BFR BUMPING ANY MID WEEK PDS FURTHER. LL TEMP GUIDANCE STILL
FVRS MORE RAIN THEN SNOW W/WARM BNDRY LYR TEMPS...HWVR DEEP
SECONDARY THU MAY YIELD ENOUGH DIABATIC/ADIABATIC COOLING TO FOSTER
MORE SNOW THEN ADVERTISED ASSUMING SRN TRACK OF ECMWF VERIFIES.
OTHERWISE TEMPS FOR MOST OF THE PD AOB NORMAL AND QUITE WET/RAW
WED-FRI.

&&

.AVIATION...
VFR COND THROUGH THE PD OUTSIDE OF MORNING FOG WINDOW. CLOUDS
ASSOC WITH WAVE LIFTING FROM THE GULF COAST WILL BRING POTENTIAL
FOR VFR CIGS ESP AT KFWA ON MONDAY.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUD
LONG TERM...HOLSTEN
AVIATION...LUD

000
FXUS63 KIND 221915
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
215 PM EST SUN NOV 22 2009

.DISCUSSION...

FORECAST FOCUS IS ON CHANCES FOR PRECIPITATION THIS WEEK.

AT 18Z HIGH PRESSURE CONTINUED TO PROVIDE WINDS FROM THE EAST ACROSS
THE FORECAST AREA THIS AFTERNOON. TEMPERATURES HAVE RESPONDED WELL
TO THE SUNSHINE ONCE AGAIN. MEANWHILE...A WEAKENING UPPER LOW WAS
NEAR SOUTHEASTERN TENNESSEE. RADAR MOSAIC SHOWED RAIN MOVING TOWARD
KENTUCKY FROM TENNESSEE.

SOME DISAGREEMENT IN THE MODELS BOTH IN MONDAY/S SYSTEM AS WELL AS
THE STRONGER ONE MID WEEK. FOR MONDAY...NAM IS DRIER THAN THE GFS
AND KEEPS RAIN WELL EAST OF THE AREA. GFS STILL SHOWS RAIN GETTING
INTO THE EASTERN PART OF THE AREA. GFS IS DOING BETTER CURRENTLY
WITH THE RAIN...SO WILL GO CLOSER TO ITS SOLUTION FOR MONDAY. BY MID
WEEK THE MODELS ARE SPLIT BETWEEN A FAST AND A SLOW SOLUTION. WITH
NO CLEAR FAVORITE...DECIDED TO SPLIT THE DIFFERENCE...ALSO TAKING
INTO ACCOUNT FORECAST CONTINUITY.

TONIGHT...CLOUDS WILL INCREASE MAINLY ACROSS THE SOUTHEASTERN HALF
OF THE AREA AS THE WEAKENING UPPPER SYSTEM MOVES NORTHEAST. THE WEAK
LIFT FROM THE SYSTEM LOOKS TO REMAIN SOUTH OF THE AREA DURING THE
NIGHT...PERHAPS GETTING INTO FAR SOUTHERN AREAS TOWARD 12Z. WITH
LITTLE LIFT AND LIMITED MOISTURE...CONTINUED THE DRY FORECAST
TONIGHT. GUIDANCE NUMBERS ARE SIMILAR FOR LOWS TONIGHT AND LOOK GOOD
GIVEN THE INCREASING CLOUDS.

THE UPPER SYSTEM PROVIDES A GLANCING BLOW TO THE AREA ON MONDAY.
WEAK ISENTROPIC LIFT ACROSS SOUTHEASTERN AREAS COULD BRING SOME
LIGHT RAIN...SO HAVE KEPT LOW POPS ACROSS THOSE AREAS. THICKER
CLOUDS ACROSS THE SOUTHEAST WILL KEEP TEMPERATURES COOLER THAN THE
NORTHWEST...AND MET GUIDANCE GENERALLY FOLLOWS THIS BETTER THAN THE
MAV...SO TRENDED TOWARD MET NUMBERS FOR HIGHS.

FIRST IN A SERIES OF UPPER LOWS WILL BEGIN TO BRING CHANCES FOR RAIN
TO THE AREA BEGINNING TUESDAY...MAINLY IN THE AFTERNOON. AS
MENTIONED EARLIER...THIS IS BETWEEN THE MODEL SOLUTIONS AND IS CLOSE
TO PREVIOUS FORECAST. THE UPPER LOW WILL THEN MOVE TO THE VICINITY
OF NORTHERN ILLINOIS BY 12Z WEDNESDAY. THUS WITH THE BETTER FORCING
ACROSS FAR NORTHERN AREAS...UPPED POPS TO LIKELY TUE NIGHT WITH
CHANCE POPS ELSEWHERE.

WHILE THERE WILL BE DRY PERIODS WEDNESDAY INTO WEDNESDAY
NIGHT...TIMING ISSUES PRECLUDE TIMING THE POPS...SO KEPT LOW POPS
THROUGH THAT PERIOD. MUCH COLDER AIR AND ANOTHER UPPER LOW ARRIVE
FOR THANKSGIVING AND THEIR ARRIVAL WILL KEEP CHANCE POPS IN THE
FORECAST. STILL LOOKS LIKE THERE WILL BE THE POTENTIAL FOR MIXED
PRECIPITATION...WITH THE THICKNESS OF THE WARM LAYER NEAR THE
SURFACE THE MAIN QUESTION. WITH SURFACE TEMPERATURES AROUND 40 AND
WET BULB TEMPERATURES NEAR FREEZING...ITS TOO TOUGH A CALL AT THIS
POINT IN TIME. WILL CONTINUE CHANCES FOR RAIN AND SNOW THANKSGIVING
AND THANKSGIVING NIGHT.

&&

.AVIATION...DISCUSSION FOR 221800Z TAF ISSUANCE.
VFR WITH INCREASING HIGH CLOUDS TONIGHT AS LOW MOVES ENE ALONG GULF
COAST.  12Z MODELS ARE LESS AGRESSIVE BRINING MID/HIGH CLOUDS...SO
WILL ONLY KEEP CIRRUS ACROSS TAFS TONIGHT WITH THE EXCEPTION OF KBMG
WHERE MID CLOUDS MAY ARRIVE BY MORNING.

LIGHT FOG POSSIBLE LATE TONIGHT AND EARLY MONDAY. BUT WITH MORE HIGH
CLOUDS...THIS SHOULD BE ENOUGH TO KEEP VBBYS OUT OF THE IFR CATEGORY.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...CS
AVIATION...JH

000
FXUS63 KIWX 221733
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1233 PM EST SUN NOV 22 2009

.AVIATION...
VFR COND THROUGH THE PD OUTSIDE OF MORNING FOG WINDOW. CLOUDS
ASSOC WITH WAVE LIFTING FROM THE GULF COAST WILL BRING POTENTIAL
FOR VFR CIGS ESP AT KFWA ON MONDAY.

&&

.PREV DISCUSSION... /ISSUED 349 AM EST SUN NOV 22 2009/

SHORT TERM...

..TODAY THROUGH MONDAY NIGHT...

RELATIVELY QUIET SHORT TERM PERIOD BEFORE MORE ACTIVE PATTERN BEGINS
TO AFFECT THE AREA. BIGGEST CONCERN WILL BE AMOUNT OF FOG THIS
MORNING AND AMOUNT OF CLOUD COVER AND POPS FOR MONDAY AND MONDAY NIGHT.

SURFACE HIGH PRESSURE OVER EASTERN GREAT LAKES PROVIDING CLEAR SKIES
AND LIGHT WINDS FOR OUR AREA THIS MORNING. FOG WAS FINALLY BEGINNING
TO FORM AROUND 07Z AND SHOULD CONTINUE AND BECOME LOCALLY DENSE BY
DAYBREAK. NO HEADLINES PLANNED AT THIS TIME AS NO SIGNS OF
WIDESPREAD DENSE FOG BUT WILL MONITOR FURTHER DEVELOPMENT.

FOG SHOULD BURN OFF THIS MORNING WITH MOSTLY SUNNY CONDITIONS
EXPECTED ONCE AGAIN. A NEARLY CARBON COPY OF SATURDAY WITH MORE SUN
IN THE SOUTHEAST. TEMPS MAY BE JUST A FEW DEGREES WARMER WITH MIXING
FROM 900MB INDICATED BY NAM12 SOUNDINGS. THIS MATCHES LATEST MOS AND
INHERITED GRIDS SO ONLY SOME MINOR TWEAKS MADE.

SHORT WAVE EXITING THE INTERMOUNTAIN WEST THIS MORNING WILL HELP
PICK UP WAVE SITTING IN DEEP SOUTH AND LIFT IT NORTHEAST. MODELS
HAVE BEEN HINTING AT INCREASING MOISTURE ACROSS OUR
AREA...ESPECIALLY IN THE EAST...LATE TONIGHT INTO MONDAY. 2100 UTC
SREF 12HR PROBABILITIES FOR MEASURABLE PCPN HAVE INCREASED TO OVER
70 PERCENT IN OUR EAST FOR MONDAY AND MONDAY MONDAY NIGHT. EXPECT
MODELS ARE OVERDOING WESTERN PERIPHERY OF MOISTURE BUT SOME LIGHT
SHOWERS ARE POSSIBLE IN FAR SOUTHEAST AND HAVE ADDED A LOW CHANCE TO
ACCOUNT FOR THIS AND FOR BETTER COLLABORATION. AMOUNTS SHOULD BE
TENTH OF AN INCH OR LESS AND THIS IS ALSO SUPPORTED BY VERY LOW SREF
PROBABILITIES FOR MORE THAN A TENTH OF AN INCH. CLOUD COVER ALSO
EXPECTED TO INCREASE SUNDAY NIGHT AND MONDAY ACROSS ENTIRE AREA AS
THESE WAVES PHASE AND MOVE ACROSS THE REGION. TEMPERATURES ON MONDAY
WILL BE A LITTLE COOLER BUT STILL ABOVE NORMAL WITH INCREASED CLOUD
COVER. SIMILAR STORY MONDAY NIGHT AHEAD OF MORE POTENT WAVE THAT
WILL BRING SIGNIFICANTLY COOLER AIR FOR LATER IN THE WEEK.

LONG TERM /TUESDAY THROUGH SATURDAY/...

GFS/ECMWF BEGINNING TO COME INTO AGREEMENT IN...AT LEAST IN TERMS OF
SLOWER ARRIVAL OF PRECIP WITH INTENSIFYING LOW PRESSURE TO THE WEST.
THE RESULT IS A SLOW DOWN IN THE ONSET OF CHC POPS FOR TUESDAY FROM
WEST TO EAST. BEST CHANCE LOOKS TO ARRIVE LATE AFTERNOON TUES AND
MORE SO TUES NGT INTO WEDS. HAVE INCREASED POPS TO 50 PERCENT TUES
NGT BUT HOLD OFF ON LIKELY AS EXACT TRACK OF LOW REMAINS A BIT
PROBLEMATIC RANGING FROM TRACKING ACROSS THE CWA TO ACROSS PORTIONS
OF WISCONSIN. ENSEMBLE GUIDANCE SHOWS THE LARGE DISPARITY IN
CONFIDENCE WITH POPS RANGING FROM 20 TO AS HIGH AS 80. ALSO WITH THE
FURTHER WEST TRACK...THERMAL PROFILES WAY TOO WARM TO SUPPORT
CONTINUED MENTION OF MIX PRECIP TUES NGT SO THIS HAS BEEN REMOVED.

PRECIP CHANCES WILL LINGER INTO WEDS NGT WHEN QUESTIONS CONTINUE AS
TO THE SPEED AND DEGREE OF THE COLD AIR IN THE WAKE OF THE SYSTEM.
GFS CONTINUES TO BE THE FASTER OF THE MEDIUM RANGE MODELS IN THE
ARRIVAL OF THE COLD AIR BY WEDS NGT VS THE ECMWF DURING THE DAY
THURS. WILL GENERALLY FOLLOW THE MEAN 850 MB TEMPS DEPICTED BY THE
GFS ENSEMBLE WHICH BRINGS READINGS INTO THE -4 TO -6 C RANGE BY
FRIDAY. DEPENDING ON AMOUNT OF CLOUD COVER...GUIDANCE MAY BE A BIT
TOO WARM WITH READING NOT FAR FROM CLIMO IN THE LOWER 40S. FOR NOW
WILL LEAVE TEMPS AND MIX PRECIP MENTION ALONE GIVEN ENOUGH TIMING
ISSUES IN EARLIER PERIODS TO RAISE A BIT OF DOUBT ON EXACT TIMING IN
LATER PERIODS. BOTH MODELS LINGER THE COOLER AIR AROUND INTO LATE
FRIDAY WHEN SOME MODERATION BEGINS...WITH THE GFS OF COURSE BEING
THE MORE EXTREME OF THE TWO MODELS.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LUD

000
FXUS63 KIND 221701
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1200 PM EST SUN NOV 22 2009

.AVIATION...DISCUSSION FOR 221800Z TAF ISSUANCE.
VFR WITH INCREASING HIGH CLOUDS TONIGHT AS LOW MOVES ENE ALONG GULF
COAST.  12Z MODELS ARE LESS AGRESSIVE BRINING MID/HIGH CLOUDS...SO
WILL ONLY KEEP CIRRUS ACROSS TAFS TONIGHT WITH THE EXCEPTION OF KBMG
WHERE MID CLOUDS MAY ARRIVE BY MORNING.

LIGHT FOG POSSIBLE LATE TONIGHT AND EARLY MONDAY. BUT WITH MORE HIGH
CLOUDS...THIS SHOULD BE ENOUGH TO KEEP VBBYS OUT OF THE IFR CATEGORY.

&&

.UPDATE...

HIGH CLOUDS WERE INCREASING RELATIVELY QUICKLY ACROSS SOUTHERN
INDIANA...SO HAVE INCREASED SKY COVER TO PARTLY CLOUDY ACROSS
SOUTHERN FORECAST AREA. TWEAKED TEMPERATURE AND WINDS TO MATCH
CURRENT CONDITIONS...OTHERWISE NO OTHER CHANGES MADE.

&&

.DISCUSSION...
SURFACE HIGH PRESSURE RIDGE REMAINS DOMINANT FEATURE EARLY THIS
MORNING...WITH CLEAR SKIES ACROSS CENTRAL INDIANA. THE PRESENCE OF
LINGERING AND SHALLOW LOW LEVEL MOISTURE COMBINED WITH LIGHT
EASTERLY FLOW CONTRIBUTING TO A GENERAL HAZE OVER THE REGION WITH
LOCALIZED AREAS OF FOG. TEMPERATURES RANGED FROM THE MID 30S TO
LOWER 40S OVER MUCH OF THE FORECAST AREA AS OF 08Z.

FORECAST CHALLENGES THIS MORNING FOCUS ON TEMPERATURES/CLOUDS
THROUGH MONDAY...POSSIBILITY FOR A FEW RAIN SHOWERS MONDAY AND
FURTHER OUT...EVOLUTION AND ARRIVAL OF THE COLDER UNSETTLED PATTERN.

CIRRUS SHIELD SLOWLY PROGRESSING NORTH THROUGH THE LOWER MISSISSIPPI
VALLEY THIS MORNING AS LOW PRESSURE MOVES ALONG THE NORTHERN GULF
COAST. GULF MOISTURE BEING PULLED NORTH ON BACK SIDE OF HIGH
PRESSURE RIDGE WITH FAIRLY UNIFORM MID LEVEL CLOUD DECK ENCOMPASSING
MUCH OF THE MID MISSISSIPPI VALLEY. DO NOT ANTICIPATE THESE CLOUDS
MOVING EAST INTO THE AREA TODAY AS HIGH PRESSURE RIDGE AND LOW LEVEL
EASTERLY FLOW SHOULD MAINTAIN BROAD SUBSIDENCE AND DRIER AIRMASS
OVER FORECAST AREA. AFOREMENTIONED CIRRUS SHIELD TO SOUTH THOUGH
WILL LIFT NORTH INT REGION THROUGH THE DAY. THE ARRIVAL OF THESE
CLOUDS SHOULD DO LITTLE TO KEEP CENTRAL INDIANA FROM SEEING ABUNDANT
SUNSHINE FOR MUCH OF THE DAY...AND PROVIDE FOR ANOTHER STELLAR
SUNDAY FOR NOVEMBER.

UPPER LOW ASSOCIATED WITH GULF COAST SYSTEM WILL BE PULLED INTO THE
TENNESSEE VALLEY THIS EVENING IN RESPONSE TO AMPLIFYING UPPER LEVEL
TROUGH OVER THE HIGH PLAINS. 00Z OP GFS...ECMWF AND GEM SOLNS ALL
PULLING DEEPER MOISTURE FURTHER NORTH AND WEST INTO THE OHIO VALLEY
BY MONDAY MORNING THAN PREVIOUS RUNS INDICATED. WHILE DEEPER FORCING
WILL REMAIN DISPLACED OVER THE CENTRAL APPALACHIANS...ISENTROPIC
LIFT DEVELOPS INTO THE SOUTHEAST FORECAST AREA MONDAY MORNING...MOST
NOTABLY AT THE 285-295K LEVELS. E/SE FLOW THROUGH THE BOUNDARY LAYER
SHOULD RETARD LOW LEVEL MOISTURE ADVECTION TO SOME DEGREE...BUT
PRESENCE OF STRONGER ISENTROPIC LIFT AND MID LEVEL MOISTURE CAN NO
LONGER BE IGNORED. HAVE INTRODUCED LOW CHANCES FOR RAIN ACROSS
EASTERN HALF OF THE FORECAST AREA FOR MONDAY. CONSIDERING A
RELATIVELY DRY BOUNDARY LAYER...EXPECT RAINFALL AMOUNTS WILL BE
LIGHT AT BEST. PRESENCE OF MID LEVEL MOISTURE SHOULD ENHANCE CLOUDS
ACROSS FORECAST AREA FOR MUCH IF NOT ALL OF THE DAY...WITH CEILINGS
LOWERING BY MONDAY NIGHT AS MODEL SOUNDINGS SUGGEST POTENTIAL FOR
STRATOCUMULUS DEVELOPMENT.

REMNANT GULF COAST UPPER LEVEL WAVE WILL LIFT OFF TO THE NORTHEAST
MONDAY NIGHT WITH ANY LIGHT RAIN/SPRINKLES ENDING. SKIES WILL REMAIN
GENERALLY CLOUDY THOUGH MONDAY NIGHT AS DEEP MOISTURE HOLDS THROUGH
THE BOUNDARY LAYER AND UNDERNEATH A DEVELOPING INVERSION. FOCUS WILL
THEN SHIFT WEST AS AFOREMENTIONED SHARP UPPER TROUGH AND ASSOCIATED
LOW PRESSURE APPROACH TUESDAY. VARIOUS MODELS HAVE COME INTO
REASONABLE AGREEMENT WITH RESPECT TO TRACK OF LOW PRESSURE FROM NEAR
KANSAS CITY TUESDAY MORNING INTO THE LOWER GREAT LAKES BY EARLY
WEDNESDAY. A TRAILING COLD FRONT WILL TRAVERSE THE REGION TUESDAY
NIGHT...AND SIGNAL THE ARRIVAL OF A MUCH COLDER AIRMASS FOR CENTRAL
INDIANA. WILL INTRODUCE CHANCE POPS TUESDAY AFTERNOON ACROSS WESTERN
FORECAST AREA AS DEEPER ISENTROPIC LIFT DEVELOPS AHEAD OF THE FRONT.
BEST CHANCES FOR WIDESPREAD RAINFALL WILL COME TUESDAY NIGHT AS LOW
LEVEL CONVERGENCE AXIS COMBINES WITH DEEP MOISTURE AND AREA OF
MID/UPPER LEVEL DIFFLUENCE AS POLAR AND SUBTROPICAL UPPER JETS
PHASE. HAVE RAISED TO 40-50 POPS FOR MUCH OF THE FORECAST AREA
TUESDAY NIGHT WITH FRONT SHIFTING EAST OF THE REGION BY EARLY
WEDNESDAY. MODEL SOUNDINGS SUPPORT POTENTIAL FOR GUSTIER WINDS ALONG
AND IMMEDIATELY BEHIND FRONTAL BOUNDARY AS 45KT 850MB LOW LEVEL JET
PASS THROUGH REGION. LOW LEVEL COLD ADVECTION BEHIND THE FRONT
SHOULD MAINTAIN STRONGER WINDS INTO WEDNESDAY MORNING.

MADE SOME MINOR ADJUSTMENTS TO WEDNESDAY AND THURSDAY AS INITIAL
UPPER LOW MOVES EAST AND IS FOLLOWED BY DEEPER UPPER LEVEL SYSTEM
FOR THANKSGIVING DAY. THE UPPER LEVEL FEATURES WILL KEEP REGION IN
COLD CYCLONIC FLOW ALOFT AND PROVIDE FIRST GOOD CHANCE AT SNOWFLAKES
FOR MUCH OF THE FORECAST AREA THIS FALL AS LOW LEVEL THICKNESSES
FALL TO NEAR OR JUST BELOW THE CRITICAL THRESHOLDS NEEDED. TWEAKED
POPS A BIT HIGHER FOR BOTH WEDNESDAY AND THURSDAY AS PLENTY OF
MOISTURE REMAINS. THANKSGIVING DAY APPEARS LIKELY TO BE THE COLDEST
DAY YET THIS MONTH FOR THE REGION.

TEMPS...UNDER A SIMILAR AIRMASS TO SATURDAY AND SEEING HOW
TEMPERATURES GENERALLY OUTPERFORMED MOS GUIDANCE...HAVE CHOSEN TO
TREND AT OR A COUPLE DEGREES ABOVE GUIDANCE FOR HIGHS TODAY.
POTENTIAL FOR LOWER 60S ACROSS THE SOUTHERN FORECAST AREA...AND
POSSIBLY AT KLAF WHICH HAS MAINTAINED ITS WARM BIAS FOR MUCH OF THE
FALL UNDER SIMILAR CONDITIONS (LIGHT WINDS/PLENTY OF SUNSHINE). TOOK
SPLIT OF COOLER MAVMOS AND WARMER METMOS FOR MONDAY WHICH ENDED UP A
FEW DEGREES COOLER THAN PREVIOUS FORECAST AS CLOUDS INCREASE.
UNDERCUT GUIDANCE AT RURAL LOCALES TONIGHT...NEAR MAVMOS FOR LOWS
ELSEWHERE TONIGHT AND OVER ENTIRE FORECAST AREA MONDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

UPDATE...CS
PUBLIC...RYAN
AVIATION...JH

000
FXUS63 KIND 221513
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1013 AM EST SUN NOV 22 2009

.UPDATE...

HIGH CLOUDS WERE INCREASING RELATIVELY QUICKLY ACROSS SOUTHERN
INDIANA...SO HAVE INCREASED SKY COVER TO PARTLY CLOUDY ACROSS
SOUTHERN FORECAST AREA. TWEAKED TEMPERATURE AND WINDS TO MATCH
CURRENT CONDITIONS...OTHERWISE NO OTHER CHANGES MADE.

&&

.AVIATION...DISCUSSION FOR 221200Z TAF ISSUANCE. PATCHY IFR/LIFR
CONDITIONS DUE TO FOG...AFFECTING MAINLY KBMG SO FAR...EXPECTED TO
MIX OUT RATHER RAPIDLY AFTER SUNRISE...AROUND 221400Z...AS MOISTURE
LAYER IS VERY SHALLOW.

OTHERWISE...NO SIGNIFICANT CLOUD COVER BELOW 050...SURFACE WINDS
BELOW 15 KTS THROUGH 230000Z.

&&

.DISCUSSION...
SURFACE HIGH PRESSURE RIDGE REMAINS DOMINANT FEATURE EARLY THIS
MORNING...WITH CLEAR SKIES ACROSS CENTRAL INDIANA. THE PRESENCE OF
LINGERING AND SHALLOW LOW LEVEL MOISTURE COMBINED WITH LIGHT
EASTERLY FLOW CONTRIBUTING TO A GENERAL HAZE OVER THE REGION WITH
LOCALIZED AREAS OF FOG. TEMPERATURES RANGED FROM THE MID 30S TO
LOWER 40S OVER MUCH OF THE FORECAST AREA AS OF 08Z.

FORECAST CHALLENGES THIS MORNING FOCUS ON TEMPERATURES/CLOUDS
THROUGH MONDAY...POSSIBILITY FOR A FEW RAIN SHOWERS MONDAY AND
FURTHER OUT...EVOLUTION AND ARRIVAL OF THE COLDER UNSETTLED PATTERN.

CIRRUS SHIELD SLOWLY PROGRESSING NORTH THROUGH THE LOWER MISSISSIPPI
VALLEY THIS MORNING AS LOW PRESSURE MOVES ALONG THE NORTHERN GULF
COAST. GULF MOISTURE BEING PULLED NORTH ON BACK SIDE OF HIGH
PRESSURE RIDGE WITH FAIRLY UNIFORM MID LEVEL CLOUD DECK ENCOMPASSING
MUCH OF THE MID MISSISSIPPI VALLEY. DO NOT ANTICIPATE THESE CLOUDS
MOVING EAST INTO THE AREA TODAY AS HIGH PRESSURE RIDGE AND LOW LEVEL
EASTERLY FLOW SHOULD MAINTAIN BROAD SUBSIDENCE AND DRIER AIRMASS
OVER FORECAST AREA. AFOREMENTIONED CIRRUS SHIELD TO SOUTH THOUGH
WILL LIFT NORTH INT REGION THROUGH THE DAY. THE ARRIVAL OF THESE
CLOUDS SHOULD DO LITTLE TO KEEP CENTRAL INDIANA FROM SEEING ABUNDANT
SUNSHINE FOR MUCH OF THE DAY...AND PROVIDE FOR ANOTHER STELLAR
SUNDAY FOR NOVEMBER.

UPPER LOW ASSOCIATED WITH GULF COAST SYSTEM WILL BE PULLED INTO THE
TENNESSEE VALLEY THIS EVENING IN RESPONSE TO AMPLIFYING UPPER LEVEL
TROUGH OVER THE HIGH PLAINS. 00Z OP GFS...ECMWF AND GEM SOLNS ALL
PULLING DEEPER MOISTURE FURTHER NORTH AND WEST INTO THE OHIO VALLEY
BY MONDAY MORNING THAN PREVIOUS RUNS INDICATED. WHILE DEEPER FORCING
WILL REMAIN DISPLACED OVER THE CENTRAL APPALACHIANS...ISENTROPIC
LIFT DEVELOPS INTO THE SOUTHEAST FORECAST AREA MONDAY MORNING...MOST
NOTABLY AT THE 285-295K LEVELS. E/SE FLOW THROUGH THE BOUNDARY LAYER
SHOULD RETARD LOW LEVEL MOISTURE ADVECTION TO SOME DEGREE...BUT
PRESENCE OF STRONGER ISENTROPIC LIFT AND MID LEVEL MOISTURE CAN NO
LONGER BE IGNORED. HAVE INTRODUCED LOW CHANCES FOR RAIN ACROSS
EASTERN HALF OF THE FORECAST AREA FOR MONDAY. CONSIDERING A
RELATIVELY DRY BOUNDARY LAYER...EXPECT RAINFALL AMOUNTS WILL BE
LIGHT AT BEST. PRESENCE OF MID LEVEL MOISTURE SHOULD ENHANCE CLOUDS
ACROSS FORECAST AREA FOR MUCH IF NOT ALL OF THE DAY...WITH CEILINGS
LOWERING BY MONDAY NIGHT AS MODEL SOUNDINGS SUGGEST POTENTIAL FOR
STRATOCUMULUS DEVELOPMENT.

REMNANT GULF COAST UPPER LEVEL WAVE WILL LIFT OFF TO THE NORTHEAST
MONDAY NIGHT WITH ANY LIGHT RAIN/SPRINKLES ENDING. SKIES WILL REMAIN
GENERALLY CLOUDY THOUGH MONDAY NIGHT AS DEEP MOISTURE HOLDS THROUGH
THE BOUNDARY LAYER AND UNDERNEATH A DEVELOPING INVERSION. FOCUS WILL
THEN SHIFT WEST AS AFOREMENTIONED SHARP UPPER TROUGH AND ASSOCIATED
LOW PRESSURE APPROACH TUESDAY. VARIOUS MODELS HAVE COME INTO
REASONABLE AGREEMENT WITH RESPECT TO TRACK OF LOW PRESSURE FROM NEAR
KANSAS CITY TUESDAY MORNING INTO THE LOWER GREAT LAKES BY EARLY
WEDNESDAY. A TRAILING COLD FRONT WILL TRAVERSE THE REGION TUESDAY
NIGHT...AND SIGNAL THE ARRIVAL OF A MUCH COLDER AIRMASS FOR CENTRAL
INDIANA. WILL INTRODUCE CHANCE POPS TUESDAY AFTERNOON ACROSS WESTERN
FORECAST AREA AS DEEPER ISENTROPIC LIFT DEVELOPS AHEAD OF THE FRONT.
BEST CHANCES FOR WIDESPREAD RAINFALL WILL COME TUESDAY NIGHT AS LOW
LEVEL CONVERGENCE AXIS COMBINES WITH DEEP MOISTURE AND AREA OF
MID/UPPER LEVEL DIFFLUENCE AS POLAR AND SUBTROPICAL UPPER JETS
PHASE. HAVE RAISED TO 40-50 POPS FOR MUCH OF THE FORECAST AREA
TUESDAY NIGHT WITH FRONT SHIFTING EAST OF THE REGION BY EARLY
WEDNESDAY. MODEL SOUNDINGS SUPPORT POTENTIAL FOR GUSTIER WINDS ALONG
AND IMMEDIATELY BEHIND FRONTAL BOUNDARY AS 45KT 850MB LOW LEVEL JET
PASS THROUGH REGION. LOW LEVEL COLD ADVECTION BEHIND THE FRONT
SHOULD MAINTAIN STRONGER WINDS INTO WEDNESDAY MORNING.

MADE SOME MINOR ADJUSTMENTS TO WEDNESDAY AND THURSDAY AS INITIAL
UPPER LOW MOVES EAST AND IS FOLLOWED BY DEEPER UPPER LEVEL SYSTEM
FOR THANKSGIVING DAY. THE UPPER LEVEL FEATURES WILL KEEP REGION IN
COLD CYCLONIC FLOW ALOFT AND PROVIDE FIRST GOOD CHANCE AT SNOWFLAKES
FOR MUCH OF THE FORECAST AREA THIS FALL AS LOW LEVEL THICKNESSES
FALL TO NEAR OR JUST BELOW THE CRITICAL THRESHOLDS NEEDED. TWEAKED
POPS A BIT HIGHER FOR BOTH WEDNESDAY AND THURSDAY AS PLENTY OF
MOISTURE REMAINS. THANKSGIVING DAY APPEARS LIKELY TO BE THE COLDEST
DAY YET THIS MONTH FOR THE REGION.

TEMPS...UNDER A SIMILAR AIRMASS TO SATURDAY AND SEEING HOW
TEMPERATURES GENERALLY OUTPERFORMED MOS GUIDANCE...HAVE CHOSEN TO
TREND AT OR A COUPLE DEGREES ABOVE GUIDANCE FOR HIGHS TODAY.
POTENTIAL FOR LOWER 60S ACROSS THE SOUTHERN FORECAST AREA...AND
POSSIBLY AT KLAF WHICH HAS MAINTAINED ITS WARM BIAS FOR MUCH OF THE
FALL UNDER SIMILAR CONDITIONS (LIGHT WINDS/PLENTY OF SUNSHINE). TOOK
SPLIT OF COOLER MAVMOS AND WARMER METMOS FOR MONDAY WHICH ENDED UP A
FEW DEGREES COOLER THAN PREVIOUS FORECAST AS CLOUDS INCREASE.
UNDERCUT GUIDANCE AT RURAL LOCALES TONIGHT...NEAR MAVMOS FOR LOWS
ELSEWHERE TONIGHT AND OVER ENTIRE FORECAST AREA MONDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

UPDATE...CS
PUBLIC...RYAN
AVIATION...JAS

000
FXUS63 KIND 221033
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
530 AM EST SUN NOV 22 2009

.AVIATION...DISCUSSION FOR 221200Z TAF ISSUANCE. PATCHY IFR/LIFR
CONDITIONS DUE TO FOG...AFFECTING MAINLY KBMG SO FAR...EXPECTED TO
MIX OUT RATHER RAPIDLY AFTER SUNRISE...AROUND 221400Z...AS MOISTURE
LAYER IS VERY SHALLOW.

OTHERWISE...NO SIGNIFICANT CLOUD COVER BELOW 050...SURFACE WINDS
BELOW 15 KTS THROUGH 230000Z.

&&

.DISCUSSION...
SURFACE HIGH PRESSURE RIDGE REMAINS DOMINANT FEATURE EARLY THIS
MORNING...WITH CLEAR SKIES ACROSS CENTRAL INDIANA. THE PRESENCE OF
LINGERING AND SHALLOW LOW LEVEL MOISTURE COMBINED WITH LIGHT
EASTERLY FLOW CONTRIBUTING TO A GENERAL HAZE OVER THE REGION WITH
LOCALIZED AREAS OF FOG. TEMPERATURES RANGED FROM THE MID 30S TO
LOWER 40S OVER MUCH OF THE FORECAST AREA AS OF 08Z.

FORECAST CHALLENGES THIS MORNING FOCUS ON TEMPERATURES/CLOUDS
THROUGH MONDAY...POSSIBILITY FOR A FEW RAIN SHOWERS MONDAY AND
FURTHER OUT...EVOLUTION AND ARRIVAL OF THE COLDER UNSETTLED PATTERN.

CIRRUS SHIELD SLOWLY PROGRESSING NORTH THROUGH THE LOWER MISSISSIPPI
VALLEY THIS MORNING AS LOW PRESSURE MOVES ALONG THE NORTHERN GULF
COAST. GULF MOISTURE BEING PULLED NORTH ON BACK SIDE OF HIGH
PRESSURE RIDGE WITH FAIRLY UNIFORM MID LEVEL CLOUD DECK ENCOMPASSING
MUCH OF THE MID MISSISSIPPI VALLEY. DO NOT ANTICIPATE THESE CLOUDS
MOVING EAST INTO THE AREA TODAY AS HIGH PRESSURE RIDGE AND LOW LEVEL
EASTERLY FLOW SHOULD MAINTAIN BROAD SUBSIDENCE AND DRIER AIRMASS
OVER FORECAST AREA. AFOREMENTIONED CIRRUS SHIELD TO SOUTH THOUGH
WILL LIFT NORTH INT REGION THROUGH THE DAY. THE ARRIVAL OF THESE
CLOUDS SHOULD DO LITTLE TO KEEP CENTRAL INDIANA FROM SEEING ABUNDANT
SUNSHINE FOR MUCH OF THE DAY...AND PROVIDE FOR ANOTHER STELLAR
SUNDAY FOR NOVEMBER.

UPPER LOW ASSOCIATED WITH GULF COAST SYSTEM WILL BE PULLED INTO THE
TENNESSEE VALLEY THIS EVENING IN RESPONSE TO AMPLIFYING UPPER LEVEL
TROUGH OVER THE HIGH PLAINS. 00Z OP GFS...ECMWF AND GEM SOLNS ALL
PULLING DEEPER MOISTURE FURTHER NORTH AND WEST INTO THE OHIO VALLEY
BY MONDAY MORNING THAN PREVIOUS RUNS INDICATED. WHILE DEEPER FORCING
WILL REMAIN DISPLACED OVER THE CENTRAL APPALACHIANS...ISENTROPIC
LIFT DEVELOPS INTO THE SOUTHEAST FORECAST AREA MONDAY MORNING...MOST
NOTABLY AT THE 285-295K LEVELS. E/SE FLOW THROUGH THE BOUNDARY LAYER
SHOULD RETARD LOW LEVEL MOISTURE ADVECTION TO SOME DEGREE...BUT
PRESENCE OF STRONGER ISENTROPIC LIFT AND MID LEVEL MOISTURE CAN NO
LONGER BE IGNORED. HAVE INTRODUCED LOW CHANCES FOR RAIN ACROSS
EASTERN HALF OF THE FORECAST AREA FOR MONDAY. CONSIDERING A
RELATIVELY DRY BOUNDARY LAYER...EXPECT RAINFALL AMOUNTS WILL BE
LIGHT AT BEST. PRESENCE OF MID LEVEL MOISTURE SHOULD ENHANCE CLOUDS
ACROSS FORECAST AREA FOR MUCH IF NOT ALL OF THE DAY...WITH CEILINGS
LOWERING BY MONDAY NIGHT AS MODEL SOUNDINGS SUGGEST POTENTIAL FOR
STRATOCUMULUS DEVELOPMENT.

REMNANT GULF COAST UPPER LEVEL WAVE WILL LIFT OFF TO THE NORTHEAST
MONDAY NIGHT WITH ANY LIGHT RAIN/SPRINKLES ENDING. SKIES WILL REMAIN
GENERALLY CLOUDY THOUGH MONDAY NIGHT AS DEEP MOISTURE HOLDS THROUGH
THE BOUNDARY LAYER AND UNDERNEATH A DEVELOPING INVERSION. FOCUS WILL
THEN SHIFT WEST AS AFOREMENTIONED SHARP UPPER TROUGH AND ASSOCIATED
LOW PRESSURE APPROACH TUESDAY. VARIOUS MODELS HAVE COME INTO
REASONABLE AGREEMENT WITH RESPECT TO TRACK OF LOW PRESSURE FROM NEAR
KANSAS CITY TUESDAY MORNING INTO THE LOWER GREAT LAKES BY EARLY
WEDNESDAY. A TRAILING COLD FRONT WILL TRAVERSE THE REGION TUESDAY
NIGHT...AND SIGNAL THE ARRIVAL OF A MUCH COLDER AIRMASS FOR CENTRAL
INDIANA. WILL INTRODUCE CHANCE POPS TUESDAY AFTERNOON ACROSS WESTERN
FORECAST AREA AS DEEPER ISENTROPIC LIFT DEVELOPS AHEAD OF THE FRONT.
BEST CHANCES FOR WIDESPREAD RAINFALL WILL COME TUESDAY NIGHT AS LOW
LEVEL CONVERGENCE AXIS COMBINES WITH DEEP MOISTURE AND AREA OF
MID/UPPER LEVEL DIFFLUENCE AS POLAR AND SUBTROPICAL UPPER JETS
PHASE. HAVE RAISED TO 40-50 POPS FOR MUCH OF THE FORECAST AREA
TUESDAY NIGHT WITH FRONT SHIFTING EAST OF THE REGION BY EARLY
WEDNESDAY. MODEL SOUNDINGS SUPPORT POTENTIAL FOR GUSTIER WINDS ALONG
AND IMMEDIATELY BEHIND FRONTAL BOUNDARY AS 45KT 850MB LOW LEVEL JET
PASS THROUGH REGION. LOW LEVEL COLD ADVECTION BEHIND THE FRONT
SHOULD MAINTAIN STRONGER WINDS INTO WEDNESDAY MORNING.

MADE SOME MINOR ADJUSTMENTS TO WEDNESDAY AND THURSDAY AS INITIAL
UPPER LOW MOVES EAST AND IS FOLLOWED BY DEEPER UPPER LEVEL SYSTEM
FOR THANKSGIVING DAY. THE UPPER LEVEL FEATURES WILL KEEP REGION IN
COLD CYCLONIC FLOW ALOFT AND PROVIDE FIRST GOOD CHANCE AT SNOWFLAKES
FOR MUCH OF THE FORECAST AREA THIS FALL AS LOW LEVEL THICKNESSES
FALL TO NEAR OR JUST BELOW THE CRITICAL THRESHOLDS NEEDED. TWEAKED
POPS A BIT HIGHER FOR BOTH WEDNESDAY AND THURSDAY AS PLENTY OF
MOISTURE REMAINS. THANKSGIVING DAY APPEARS LIKELY TO BE THE COLDEST
DAY YET THIS MONTH FOR THE REGION.

TEMPS...UNDER A SIMILAR AIRMASS TO SATURDAY AND SEEING HOW
TEMPERATURES GENERALLY OUTPERFORMED MOS GUIDANCE...HAVE CHOSEN TO
TREND AT OR A COUPLE DEGREES ABOVE GUIDANCE FOR HIGHS TODAY.
POTENTIAL FOR LOWER 60S ACROSS THE SOUTHERN FORECAST AREA...AND
POSSIBLY AT KLAF WHICH HAS MAINTAINED ITS WARM BIAS FOR MUCH OF THE
FALL UNDER SIMILAR CONDITIONS (LIGHT WINDS/PLENTY OF SUNSHINE). TOOK
SPLIT OF COOLER MAVMOS AND WARMER METMOS FOR MONDAY WHICH ENDED UP A
FEW DEGREES COOLER THAN PREVIOUS FORECAST AS CLOUDS INCREASE.
UNDERCUT GUIDANCE AT RURAL LOCALES TONIGHT...NEAR MAVMOS FOR LOWS
ELSEWHERE TONIGHT AND OVER ENTIRE FORECAST AREA MONDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...JAS

000
FXUS63 KIWX 220849
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
349 AM EST SUN NOV 22 2009

.SHORT TERM...

...TODAY THROUGH MONDAY NIGHT...

RELATIVELY QUIET SHORT TERM PERIOD BEFORE MORE ACTIVE PATTERN BEGINS
TO AFFECT THE AREA. BIGGEST CONCERN WILL BE AMOUNT OF FOG THIS
MORNING AND AMOUNT OF CLOUD COVER AND POPS FOR MONDAY AND MONDAY NIGHT.

SURFACE HIGH PRESSURE OVER EASTERN GREAT LAKES PROVIDING CLEAR SKIES
AND LIGHT WINDS FOR OUR AREA THIS MORNING. FOG WAS FINALLY BEGINNING
TO FORM AROUND 07Z AND SHOULD CONTINUE AND BECOME LOCALLY DENSE BY
DAYBREAK. NO HEADLINES PLANNED AT THIS TIME AS NO SIGNS OF
WIDESPREAD DENSE FOG BUT WILL MONITOR FURTHER DEVELOPMENT.

FOG SHOULD BURN OFF THIS MORNING WITH MOSTLY SUNNY CONDITIONS
EXPECTED ONCE AGAIN. A NEARLY CARBON COPY OF SATURDAY WITH MORE SUN
IN THE SOUTHEAST. TEMPS MAY BE JUST A FEW DEGREES WARMER WITH MIXING
FROM 900MB INDICATED BY NAM12 SOUNDINGS. THIS MATCHES LATEST MOS AND
INHERITED GRIDS SO ONLY SOME MINOR TWEAKS MADE.

SHORT WAVE EXITING THE INTERMOUNTAIN WEST THIS MORNING WILL HELP
PICK UP WAVE SITTING IN DEEP SOUTH AND LIFT IT NORTHEAST. MODELS
HAVE BEEN HINTING AT INCREASING MOISTURE ACROSS OUR
AREA...ESPECIALLY IN THE EAST...LATE TONIGHT INTO MONDAY. 2100 UTC
SREF 12HR PROBABILITIES FOR MEASURABLE PCPN HAVE INCREASED TO OVER
70 PERCENT IN OUR EAST FOR MONDAY AND MONDAY MONDAY NIGHT. EXPECT
MODELS ARE OVERDOING WESTERN PERIPHERY OF MOISTURE BUT SOME LIGHT
SHOWERS ARE POSSIBLE IN FAR SOUTHEAST AND HAVE ADDED A LOW CHANCE TO
ACCOUNT FOR THIS AND FOR BETTER COLLABORATION. AMOUNTS SHOULD BE
TENTH OF AN INCH OR LESS AND THIS IS ALSO SUPPORTED BY VERY LOW SREF
PROBABILITIES FOR MORE THAN A TENTH OF AN INCH. CLOUD COVER ALSO
EXPECTED TO INCREASE SUNDAY NIGHT AND MONDAY ACROSS ENTIRE AREA AS
THESE WAVES PHASE AND MOVE ACROSS THE REGION. TEMPERATURES ON MONDAY
WILL BE A LITTLE COOLER BUT STILL ABOVE NORMAL WITH INCREASED CLOUD
COVER. SIMILAR STORY MONDAY NIGHT AHEAD OF MORE POTENT WAVE THAT
WILL BRING SIGNIFICANTLY COOLER AIR FOR LATER IN THE WEEK.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...

GFS/ECMWF BEGINNING TO COME INTO AGREEMENT IN...AT LEAST IN TERMS OF
SLOWER ARRIVAL OF PRECIP WITH INTENSIFYING LOW PRESSURE TO THE WEST.
THE RESULT IS A SLOW DOWN IN THE ONSET OF CHC POPS FOR TUESDAY FROM
WEST TO EAST. BEST CHANCE LOOKS TO ARRIVE LATE AFTERNOON TUES AND
MORE SO TUES NGT INTO WEDS. HAVE INCREASED POPS TO 50 PERCENT TUES
NGT BUT HOLD OFF ON LIKELY AS EXACT TRACK OF LOW REMAINS A BIT
PROBLEMATIC RANGING FROM TRACKING ACROSS THE CWA TO ACROSS PORTIONS
OF WISCONSIN. ENSEMBLE GUIDANCE SHOWS THE LARGE DISPARITY IN
CONFIDENCE WITH POPS RANGING FROM 20 TO AS HIGH AS 80. ALSO WITH THE
FURTHER WEST TRACK...THERMAL PROFILES WAY TOO WARM TO SUPPORT
CONTINUED MENTION OF MIX PRECIP TUES NGT SO THIS HAS BEEN REMOVED.

PRECIP CHANCES WILL LINGER INTO WEDS NGT WHEN QUESTIONS CONTINUE AS
TO THE SPEED AND DEGREE OF THE COLD AIR IN THE WAKE OF THE SYSTEM.
GFS CONTINUES TO BE THE FASTER OF THE MEDIUM RANGE MODELS IN THE
ARRIVAL OF THE COLD AIR BY WEDS NGT VS THE ECMWF DURING THE DAY
THURS. WILL GENERALLY FOLLOW THE MEAN 850 MB TEMPS DEPICTED BY THE
GFS ENSEMBLE WHICH BRINGS READINGS INTO THE -4 TO -6 C RANGE BY
FRIDAY. DEPENDING ON AMOUNT OF CLOUD COVER...GUIDANCE MAY BE A BIT
TOO WARM WITH READING NOT FAR FROM CLIMO IN THE LOWER 40S. FOR NOW
WILL LEAVE TEMPS AND MIX PRECIP MENTION ALONE GIVEN ENOUGH TIMING
ISSUES IN EARLIER PERIODS TO RAISE A BIT OF DOUBT ON EXACT TIMING IN
LATER PERIODS. BOTH MODELS LINGER THE COOLER AIR AROUND INTO LATE
FRIDAY WHEN SOME MODERATION BEGINS...WITH THE GFS OF COURSE BEING
THE MORE EXTREME OF THE TWO MODELS.

&&

.AVIATION...
HIGH PRESSURE OVER THE AREA WITH CLEAR SKIES AND LIGHT WINDS
TONIGHT. EXPECT MVFR BR TO DEVELOP WITH IFR POSSIBLE TOWARD
DAYBREAK. SHOULD SEE THIS BURN OFF QUICKLY AFTER SUNRISE WITH RETURN
TO VFR CONDITIONS.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LASHLEY

000
FXUS63 KIND 220845 AAA
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
344 AM EST SUN NOV 22 2009

.DISCUSSION...
SURFACE HIGH PRESSURE RIDGE REMAINS DOMINANT FEATURE EARLY THIS
MORNING...WITH CLEAR SKIES ACROSS CENTRAL INDIANA. THE PRESENCE OF
LINGERING AND SHALLOW LOW LEVEL MOISTURE COMBINED WITH LIGHT
EASTERLY FLOW CONTRIBUTING TO A GENERAL HAZE OVER THE REGION WITH
LOCALIZED AREAS OF FOG. TEMPERATURES RANGED FROM THE MID 30S TO
LOWER 40S OVER MUCH OF THE FORECAST AREA AS OF 08Z.

FORECAST CHALLENGES THIS MORNING FOCUS ON TEMPERATURES/CLOUDS
THROUGH MONDAY...POSSIBILITY FOR A FEW RAIN SHOWERS MONDAY AND
FURTHER OUT...EVOLUTION AND ARRIVAL OF THE COLDER UNSETTLED PATTERN.

CIRRUS SHIELD SLOWLY PROGRESSING NORTH THROUGH THE LOWER MISSISSIPPI
VALLEY THIS MORNING AS LOW PRESSURE MOVES ALONG THE NORTHERN GULF
COAST. GULF MOISTURE BEING PULLED NORTH ON BACK SIDE OF HIGH
PRESSURE RIDGE WITH FAIRLY UNIFORM MID LEVEL CLOUD DECK ENCOMPASSING
MUCH OF THE MID MISSISSIPPI VALLEY. DO NOT ANTICIPATE THESE CLOUDS
MOVING EAST INTO THE AREA TODAY AS HIGH PRESSURE RIDGE AND LOW LEVEL
EASTERLY FLOW SHOULD MAINTAIN BROAD SUBSIDENCE AND DRIER AIRMASS
OVER FORECAST AREA. AFOREMENTIONED CIRRUS SHIELD TO SOUTH THOUGH
WILL LIFT NORTH INT REGION THROUGH THE DAY. THE ARRIVAL OF THESE
CLOUDS SHOULD DO LITTLE TO KEEP CENTRAL INDIANA FROM SEEING ABUNDANT
SUNSHINE FOR MUCH OF THE DAY...AND PROVIDE FOR ANOTHER STELLAR
SUNDAY FOR NOVEMBER.

UPPER LOW ASSOCIATED WITH GULF COAST SYSTEM WILL BE PULLED INTO THE
TENNESSEE VALLEY THIS EVENING IN RESPONSE TO AMPLIFYING UPPER LEVEL
TROUGH OVER THE HIGH PLAINS. 00Z OP GFS...ECMWF AND GEM SOLNS ALL
PULLING DEEPER MOISTURE FURTHER NORTH AND WEST INTO THE OHIO VALLEY
BY MONDAY MORNING THAN PREVIOUS RUNS INDICATED. WHILE DEEPER FORCING
WILL REMAIN DISPLACED OVER THE CENTRAL APPALACHIANS...ISENTROPIC
LIFT DEVELOPS INTO THE SOUTHEAST FORECAST AREA MONDAY MORNING...MOST
NOTABLY AT THE 285-295K LEVELS. E/SE FLOW THROUGH THE BOUNDARY LAYER
SHOULD RETARD LOW LEVEL MOISTURE ADVECTION TO SOME DEGREE...BUT
PRESENCE OF STRONGER ISENTROPIC LIFT AND MID LEVEL MOISTURE CAN NO
LONGER BE IGNORED. HAVE INTRODUCED LOW CHANCES FOR RAIN ACROSS
EASTERN HALF OF THE FORECAST AREA FOR MONDAY. CONSIDERING A
RELATIVELY DRY BOUNDARY LAYER...EXPECT RAINFALL AMOUNTS WILL BE
LIGHT AT BEST. PRESENCE OF MID LEVEL MOISTURE SHOULD ENHANCE CLOUDS
ACROSS FORECAST AREA FOR MUCH IF NOT ALL OF THE DAY...WITH CEILINGS
LOWERING BY MONDAY NIGHT AS MODEL SOUNDINGS SUGGEST POTENTIAL FOR
STRATOCUMULUS DEVELOPMENT.

REMNANT GULF COAST UPPER LEVEL WAVE WILL LIFT OFF TO THE NORTHEAST
MONDAY NIGHT WITH ANY LIGHT RAIN/SPRINKLES ENDING. SKIES WILL REMAIN
GENERALLY CLOUDY THOUGH MONDAY NIGHT AS DEEP MOISTURE HOLDS THROUGH
THE BOUNDARY LAYER AND UNDERNEATH A DEVELOPING INVERSION. FOCUS WILL
THEN SHIFT WEST AS AFOREMENTIONED SHARP UPPER TROUGH AND ASSOCIATED
LOW PRESSURE APPROACH TUESDAY. VARIOUS MODELS HAVE COME INTO
REASONABLE AGREEMENT WITH RESPECT TO TRACK OF LOW PRESSURE FROM NEAR
KANSAS CITY TUESDAY MORNING INTO THE LOWER GREAT LAKES BY EARLY
WEDNESDAY. A TRAILING COLD FRONT WILL TRAVERSE THE REGION TUESDAY
NIGHT...AND SIGNAL THE ARRIVAL OF A MUCH COLDER AIRMASS FOR CENTRAL
INDIANA. WILL INTRODUCE CHANCE POPS TUESDAY AFTERNOON ACROSS WESTERN
FORECAST AREA AS DEEPER ISENTROPIC LIFT DEVELOPS AHEAD OF THE FRONT.
BEST CHANCES FOR WIDESPREAD RAINFALL WILL COME TUESDAY NIGHT AS LOW
LEVEL CONVERGENCE AXIS COMBINES WITH DEEP MOISTURE AND AREA OF
MID/UPPER LEVEL DIFFLUENCE AS POLAR AND SUBTROPICAL UPPER JETS
PHASE. HAVE RAISED TO 40-50 POPS FOR MUCH OF THE FORECAST AREA
TUESDAY NIGHT WITH FRONT SHIFTING EAST OF THE REGION BY EARLY
WEDNESDAY. MODEL SOUNDINGS SUPPORT POTENTIAL FOR GUSTIER WINDS ALONG
AND IMMEDIATELY BEHIND FRONTAL BOUNDARY AS 45KT 850MB LOW LEVEL JET
PASS THROUGH REGION. LOW LEVEL COLD ADVECTION BEHIND THE FRONT
SHOULD MAINTAIN STRONGER WINDS INTO WEDNESDAY MORNING.

MADE SOME MINOR ADJUSTMENTS TO WEDNESDAY AND THURSDAY AS INITIAL
UPPER LOW MOVES EAST AND IS FOLLOWED BY DEEPER UPPER LEVEL SYSTEM
FOR THANKSGIVING DAY. THE UPPER LEVEL FEATURES WILL KEEP REGION IN
COLD CYCLONIC FLOW ALOFT AND PROVIDE FIRST GOOD CHANCE AT SNOWFLAKES
FOR MUCH OF THE FORECAST AREA THIS FALL AS LOW LEVEL THICKNESSES
FALL TO NEAR OR JUST BELOW THE CRITICAL THRESHOLDS NEEDED. TWEAKED
POPS A BIT HIGHER FOR BOTH WEDNESDAY AND THURSDAY AS PLENTY OF
MOISTURE REMAINS. THANKSGIVING DAY APPEARS LIKELY TO BE THE COLDEST
DAY YET THIS MONTH FOR THE REGION.

TEMPS...UNDER A SIMILAR AIRMASS TO SATURDAY AND SEEING HOW
TEMPERATURES GENERALLY OUTPERFORMED MOS GUIDANCE...HAVE CHOSEN TO
TREND AT OR A COUPLE DEGREES ABOVE GUIDANCE FOR HIGHS TODAY.
POTENTIAL FOR LOWER 60S ACROSS THE SOUTHERN FORECAST AREA...AND
POSSIBLY AT KLAF WHICH HAS MAINTAINED ITS WARM BIAS FOR MUCH OF THE
FALL UNDER SIMILAR CONDITIONS (LIGHT WINDS/PLENTY OF SUNSHINE). TOOK
SPLIT OF COOLER MAVMOS AND WARMER METMOS FOR MONDAY WHICH ENDED UP A
FEW DEGREES COOLER THAN PREVIOUS FORECAST AS CLOUDS INCREASE.
UNDERCUT GUIDANCE AT RURAL LOCALES TONIGHT...NEAR MAVMOS FOR LOWS
ELSEWHERE TONIGHT AND OVER ENTIRE FORECAST AREA MONDAY NIGHT.

&&

.AVIATION DISCUSSION...FOR THE 06Z TAFS
HIGH PRESSURE EXTENDED FROM THE NEW ENGLAND STATES THROUGH THE GREAT
LAKES. THIS WILL BE THE MAIN WEATHER SYSTEM CONTROLLING INDIANAS
WEATHER. CLEAR SKIES...CALM WINDS AND SOME LOW LEVEL MOISTURE HAS
CAUSED FOG TO DEVELOP. VISIBILITIES WILL DECREASE TO IFR LEVELS BY
09Z. AT HUF...LAF AND ESPECIALLY BMG WHERE THERE IS LESS URBAN
INFLUENCE THERE MAY BE SOME LIFR CONDITIONS PERIODS. THE SKIES WILL
BE CLEAR WHICH WILL CAUSE RAPID MIXING AFTER SUNRISE CAUSING
CONDITIONS TO QUICKLY IMPROVE TO VFR. VFR CONDITIONS WILL THEN
CONTINUE THROUGH THE REST OF THE TAF.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...SH

000
FXUS63 KIWX 220522
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1230 AM EST SUN NOV 22 2009

.AVIATION...
HIGH PRESSURE OVER THE AREA WITH CLEAR SKIES AND LIGHT WINDS
TONIGHT. EXPECT MVFR BR TO DEVELOP WITH IFR POSSIBLE TOWARD
DAYBREAK. SHOULD SEE THIS BURN OFF QUICKLY AFTER SUNRISE WITH RETURN
TO VFR CONDITIONS.

&&

.SHORT TERM...
UPPER RIDGE IS BUILDING OVER THE CWA THIS AFTERNOON AS SFC
RIDGING SLIDES SLOWLY EAST RESULTING IN A SUNNY DAY FOR MOST AS AN
AREA OF LATENT STRATUS CLOUDS DISSOLVES OVER SOUTH CENTRAL
COUNTIES. SIGNIFICANT MORNING FOG DEVELOPED UPSTREAM IN THE
ENVIRONMENT THAT WILL TRANSLATE OVERHEAD BY MORNING BRINGING A
REPEAT OF FOGGY CONDITIONS INTO MID/LATE MORNING AS MOSTLY CLEAR
SKIES AND LIGHT WINDS ON WEST SIDE OF DEPARTING SFC RIDGE ALLOWS
EFFECTIVE COOLING WHILE LLEVEL MOISTURE REMAINS IN PLACE PER TIME
HEIGHTS.

ON SUNDAY SUNSHINE WILL AGAIN MAKE ITS PRESENCE FELT ONCE MORNING
FOG/LOW STRATUS MIXES OUT THOUGH AS WITH TODAY SOME LOCATIONS MAY
NOT CLEAR OUT UNTIL MID TO LATE MORNING. TOMORROW AFTERNOON WILL
BE A BIT WARMER THAN TODAY AS TEMPS ALOFT AT H92 RISE A BIT WITH
SOUTHERLY FLOW DEVELOPING IN EARNEST TO JUST TO OUR WEST ON THE
BACK SIDE OF RETREATING LLEVEL RIDGE. ADEQUATE MIXING WOULD SEE
HIGHS REACH THE MID TO UPPER 50S WHICH IS IN LINE WITH A MET/MAV
GUIDANCE BLEND AND VERY SIMILAR TO INHERITED FORECAST.

BY MONDAY NIGHT DEEPER MOISTURE BEINGS TO ENCROACH FROM THE SOUTH
AHEAD OF WAVE LIFTING AWAY FROM THE GULF COAST WITH INCREASING
GRADIENT FLOW...SO WILL HOLD OFF ON ANY ADDITIONAL FOG MENTION FOR
MONDAY NIGHT AT THIS POINT WITH SLIGHTLY MILDER LOW TEMPS.

 &&

.LONG TERM...
MED RANGE GUIDANCE IN GOOD AGREEMENT INTO LT WEEK BFR DEPARTING WAYS
NXT WEEKEND. PARADE OF SW TROUGHS EMBEDDED WITHIN PERTURBED HIGH
MOMENTUM FLW ACRS THE NRN PACIFIC PROMISE AN UNSETTLED END TO
NOVEMBER. LEAD SW INTO THE SW US WILL DO LTL OTHER THAN DISLODGE
INTENSE SRN STREAM SW OVR LA SHRT TERM. MORE POTENT WAVE OUT NR 140W
WILL DIG INLAND SUN AND EMERGE OVR THE CNTRL PLAINS MON. CONTD
INTENSIFICATION SHLD LEAD TO A DECENT FNTL RAIN BAND TUE ALTHOUGH
STREAM SEPARATION AND WK MID LVL RIDGING ACRS THE GOMEX SUGGEST NO
SIG LL MSTR ENTRAINMENT INTO THIS SYS AND WILL CONT TO RIDE LOW CHC
POPS. MORE SUBSTANTIAL AMPLIFICATION UPSTREAM OF THIS SYS TIED TO
MORE SIG LW TROUGHING DVLPG ACRS THE NEPAC LT WEEK ALLOWS SECONDARY
FOLLOWING WAVE TO REINFORCE DEEPENING GREAT LAKES TROUGH AND FAIRLY
IMPRESSIVE SURGE OF COLD AIR THU/FRI WHICH LOOKS FVRBL FOR CONTD
RAIN/SNOW MENTION ALTHOUGH 12Z GUIDANCE WOULD BODILY FVR A BTR CHC
OF RAIN W/BNDRY LYR LOOKING A BIT TOO WARM.

OTHERWISE TEMPS NR NORMAL TO START...TAILING OFF TO BLO NORMAL BY
THANKSGIVING AND INTO NXT WEEKEND.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUD
LONG TERM...HOLSTEN
AVIATION...LASHLEY

000
FXUS63 KIND 220430 AAA
AFDIND

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1130 PM EST SAT NOV 21 2009

.AVIATION DISCUSSION...FOR THE 06Z TAFS
HIGH PRESSURE EXTENDED FROM THE NEW ENGLAND STATES THROUGH THE GREAT
LAKES. THIS WILL BE THE MAIN WEATHER SYSTEM CONTROLLING INDIANAS
WEATHER. CLEAR SKIES...CALM WINDS AND SOME LOW LEVEL MOISTURE HAS
CAUSED FOG TO DEVELOP. VISIBILITIES WILL DECREASE TO IFR LEVELS BY
09Z. AT HUF...LAF AND ESPECIALLY BMG WHERE THERE IS LESS URBAN
INFLUENCE THERE MAY BE SOME LIFR CONDITIONS PERIODS. THE SKIES WILL
BE CLEAR WHICH WILL CAUSE RAPID MIXING AFTER SUNRISE CAUSING
CONDITIONS TO QUICKLY IMPROVE TO VFR. VFR CONDITIONS WILL THEN
CONTINUE THROUGH THE REST OF THE TAF.

&&

.DISCUSSION...
QUIET WEATHER WAS THE RULE AS HIGH PRESSURE WAS CENTERED OVER THE
EASTERN GREAT LAKES AND OHIO. VISIBLE SATELLITE SHOWED PATCHY LOW
CLOUDS ACROSS OUR FAR NORTHEAST. OTHERWISE SKIES WERE MOSTLY CLEAR
ACROSS OUR REGION.  WATER VAPOR IR SHOWED A WEAK UPPER TROUGH OVER
THE ST. LAWRENCE VALLEY AND UPPER LOW OVER EAST TEXAS AND AN UPPER
RIDGE FROM THE CENTRAL PLAINS TO LAKE SUPERIOR.

MAIN FORECAST CHALLENGES ARE WHETHER TO MENTION ANY PATCHY FOG LATE
TONIGHT. RAIN CHANCES EARLY TO MIDDLE OF NEXT WEEK AND PRECIPITATION
CHANCES AND TYPE AROUND THANKSGIVING.

CONCERNING FOG TONIGHT...DEWPOINTS ARE PRESENTLY HIGHER THAN
FORETASTED LOWS.  ON THE OTHER HAND MODELS BRING SOME SLIGHTLY DRIER
AIR IN LATER TONIGHT. NAM SHOWS A WEAK ESE GRADIENT DEVELOPING
OVERNIGHT ESPECIALLY ACROSS OUR SOUTH AND THIS SHOULD BE ENOUGH TO
LIMIT ANY FOG THERE. ACROSS OUR NORTH AND NE WINDS SHOULD REMAIN
LIGHT AND WILL MENTION PATCHY FOG THAT AREA LATE TONIGHT. ALSO WITH
CLEAR SKIES TEMPERATURES DROPPED A LITTLE COOLER THAN MET/MAV BLEND
IN THE AREAS WITH LIGHT OR NO WINDS.

MILD AND UNEVENTFUL WEATHER WILL BE THE RULE SUNDAY.  MOST MODELS
STILL KEEP PRECIP SOUTH OF OUR REGION AS THE UPPER LOW MOVES EAST
ALONG THE GULF COAST STATES.  WE WILL PROBABLY SEE INCREASING MID
AND HIGH CLOUDS LATE SUNDAY INTO MONDAY.

THE NAM/GFS/GEM AND EUROPEAN BRING THE NEXT COLD FRONT TO THE
ILLINOIS BORDER BY 00Z WEDNESDAY AND THEN ACROSS OUR AREA TUESDAY
EVENING.  WILL DROP MENTION OF ANY RAIN CHANCES ACROSS OUR EASTERN
HALF TUESDAY MORNING AS MODELS KEEP ALL PRECIP CLOSER TO FRONT.

LIGHT PRECIP STILL LOOKS POSSIBLE WEDNESDAY AND THURSDAY AS THE
UPPER LOW DEEPENS OVER THE UPPER MIDWEST AND THEN MOVES EAST ACROSS
THE SOUTHERN GREAT LAKES ON THURSDAY. THERE ARE STILL MINOR
DISAGREEMENTS BETWEEN MODELS ON COLD IT WILL GET.  MOST MODELS SHOW
LOW LEVEL THICKNESS COLD ENOUGH FOR AT LEAST MIXED RAIN AND SNOW BY
THURSDAY.  SO WILL CONTINUE LOW CHANCES OF RAIN AND SNOW SHOWERS.

DRY WEATHER WILL BE THE RULE FRIDAY AND SATURDAY AS THE UPPER LOW
CONTINUES MOVING EAST.  MODELS BUILD A WEAK UPPER RIDGE INTO THE
MISSISSIPPI VALLEY BY SATURDAY.

AS FAR AS TEMPERATURES ARE CONCERNED WENT A LITTLE LOWER THAN
MAV/MET BLEND AS SKIES WILL BE CLEAR AND WINDS WILL BE LIGHT
ESPECIALLY ACROSS OUR NORTH AND NORTHEAST.  DID NOT MAKE ANY
SIGNIFICANT CHANGES TO MOST OTHER PERIODS.  BUT I WENT A LITTLE
COOLER THAN HPC AROUND THANKSGIVING DAY AS THE UPPER LOW MOVES BY
AND MOST MODELS INDICATE THIS PERIOD IS WHEN THE COLDEST AIR WILL BE
MOVING ACROSS OUR REGION.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH

000
FXUS63 KIND 220307 AAA
AFDIND

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1000 PM EST SAT NOV 21 2009

.AVIATION DISCUSSION...FOR THE 00Z TAFS
HIGH PRESSURE WILL BE THE MAIN WEATHER SYSTEM CONTROLLING INDIANAS
WEATHER. DUE TO THE CLEAR SKIES AND CALM WINDS THERE MAY BE SOME
AREAS OF MVFR VISIBILITIES AROUND SUNRISE. INCLUDED THIS IN ALL BUT
IND TAF. WHERE THERE SHOULD BE MIXING DUE TO THE CITY TO KEEP
VISIBILITIES VFR. THE FOG COVERAGE WILL BE THE GREATEST AT BMG WHICH
WILL HAVE PERIODS OF LIFR. CONDITIONS WILL QUICKLY IMPROVE AFTER
SUNRISE. A WARM FRONT WILL MOVE INTO KENTUCKY SUNDAY AFTERNOON. DUE
TO THE LACK OF MOISTURE ONLY EFFECT WILL BE SOME HIGH CLOUDS.

&&

.DISCUSSION...
QUIET WEATHER WAS THE RULE AS HIGH PRESSURE WAS CENTERED OVER THE
EASTERN GREAT LAKES AND OHIO. VISIBLE SATELLITE SHOWED PATCHY LOW
CLOUDS ACROSS OUR FAR NORTHEAST. OTHERWISE SKIES WERE MOSTLY CLEAR
ACROSS OUR REGION.  WATER VAPOR IR SHOWED A WEAK UPPER TROUGH OVER
THE ST. LAWRENCE VALLEY AND UPPER LOW OVER EAST TEXAS AND AN UPPER
RIDGE FROM THE CENTRAL PLAINS TO LAKE SUPERIOR.

MAIN FORECAST CHALLENGES ARE WHETHER TO MENTION ANY PATCHY FOG LATE
TONIGHT. RAIN CHANCES EARLY TO MIDDLE OF NEXT WEEK AND PRECIPITATION
CHANCES AND TYPE AROUND THANKSGIVING.

CONCERNING FOG TONIGHT...DEWPOINTS ARE PRESENTLY HIGHER THAN
FORETASTED LOWS.  ON THE OTHER HAND MODELS BRING SOME SLIGHTLY DRIER
AIR IN LATER TONIGHT. NAM SHOWS A WEAK ESE GRADIENT DEVELOPING
OVERNIGHT ESPECIALLY ACROSS OUR SOUTH AND THIS SHOULD BE ENOUGH TO
LIMIT ANY FOG THERE. ACROSS OUR NORTH AND NE WINDS SHOULD REMAIN
LIGHT AND WILL MENTION PATCHY FOG THAT AREA LATE TONIGHT. ALSO WITH
CLEAR SKIES TEMPERATURES DROPPED A LITTLE COOLER THAN MET/MAV BLEND
IN THE AREAS WITH LIGHT OR NO WINDS.

MILD AND UNEVENTFUL WEATHER WILL BE THE RULE SUNDAY.  MOST MODELS
STILL KEEP PRECIP SOUTH OF OUR REGION AS THE UPPER LOW MOVES EAST
ALONG THE GULF COAST STATES.  WE WILL PROBABLY SEE INCREASING MID
AND HIGH CLOUDS LATE SUNDAY INTO MONDAY.

THE NAM/GFS/GEM AND EUROPEAN BRING THE NEXT COLD FRONT TO THE
ILLINOIS BORDER BY 00Z WEDNESDAY AND THEN ACROSS OUR AREA TUESDAY
EVENING.  WILL DROP MENTION OF ANY RAIN CHANCES ACROSS OUR EASTERN
HALF TUESDAY MORNING AS MODELS KEEP ALL PRECIP CLOSER TO FRONT.

LIGHT PRECIP STILL LOOKS POSSIBLE WEDNESDAY AND THURSDAY AS THE
UPPER LOW DEEPENS OVER THE UPPER MIDWEST AND THEN MOVES EAST ACROSS
THE SOUTHERN GREAT LAKES ON THURSDAY. THERE ARE STILL MINOR
DISAGREEMENTS BETWEEN MODELS ON COLD IT WILL GET.  MOST MODELS SHOW
LOW LEVEL THICKNESS COLD ENOUGH FOR AT LEAST MIXED RAIN AND SNOW BY
THURSDAY.  SO WILL CONTINUE LOW CHANCES OF RAIN AND SNOW SHOWERS.

DRY WEATHER WILL BE THE RULE FRIDAY AND SATURDAY AS THE UPPER LOW
CONTINUES MOVING EAST.  MODELS BUILD A WEAK UPPER RIDGE INTO THE
MISSISSIPPI VALLEY BY SATURDAY.

AS FAR AS TEMPERATURES ARE CONCERNED WENT A LITTLE LOWER THAN
MAV/MET BLEND AS SKIES WILL BE CLEAR AND WINDS WILL BE LIGHT
ESPECIALLY ACROSS OUR NORTH AND NORTHEAST.  DID NOT MAKE ANY
SIGNIFICANT CHANGES TO MOST OTHER PERIODS.  BUT I WENT A LITTLE
COOLER THAN HPC AROUND THANKSGIVING DAY AS THE UPPER LOW MOVES BY
AND MOST MODELS INDICATE THIS PERIOD IS WHEN THE COLDEST AIR WILL BE
MOVING ACROSS OUR REGION.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH

000
FXUS63 KIND 220305
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1005 PM EST SAT NOV 21 2009

.UPDATE...
INSERTED CURRENT OBS...OTHERWISE FORECAST ON TRACK.


&&

.PREV DISCUSSION... /ISSUED 600 PM EST SAT NOV 21 2009/

AVIATION DISCUSSION...FOR THE 00Z TAFS
VFR CONDITIONS THROUGH THE TAF PERIOD. HIGH PRESSURE WILL BE THE
MAIN WEATHER SYSTEM CONTROLLING INDIANAS WEATHER. DRYING OF SURFACE
DURING THE PAST 2 DAYS WILL LIMIT FOG DEVELOPMENT. DUE TO THE CLEAR
SKIES AND CALM WINDS THERE MAY BE SOME AREAS OF MVFR VISIBILITIES
AROUND SUNRISE. INCLUDED THIS IN ALL BUT IND TAF. THERE SHOULD BE
MIXING DUE TO THE CITY TO KEEP VISIBILITIES VFR. A WARM FRONT WILL
MOVE INTO KENTUCKY SUNDAY AFTERNOON. DUE TO THE LACK OF MOISTURE
ONLY EFFECT WILL BE SOME HIGH CLOUDS.

DISCUSSION...
QUIET WEATHER WAS THE RULE AS HIGH PRESSURE WAS CENTERED OVER THE
EASTERN GREAT LAKES AND OHIO. VISIBLE SATELLITE SHOWED PATCHY LOW
CLOUDS ACROSS OUR FAR NORTHEAST. OTHERWISE SKIES WERE MOSTLY CLEAR
ACROSS OUR REGION.  WATER VAPOR IR SHOWED A WEAK UPPER TROUGH OVER
THE ST. LAWRENCE VALLEY AND UPPER LOW OVER EAST TEXAS AND AN UPPER
RIDGE FROM THE CENTRAL PLAINS TO LAKE SUPERIOR.

MAIN FORECAST CHALLENGES ARE WHETHER TO MENTION ANY PATCHY FOG LATE
TONIGHT. RAIN CHANCES EARLY TO MIDDLE OF NEXT WEEK AND PRECIPITATION
CHANCES AND TYPE AROUND THANKSGIVING.

CONCERNING FOG TONIGHT...DEWPOINTS ARE PRESENTLY HIGHER THAN
FORETASTED LOWS.  ON THE OTHER HAND MODELS BRING SOME SLIGHTLY DRIER
AIR IN LATER TONIGHT. NAM SHOWS A WEAK ESE GRADIENT DEVELOPING
OVERNIGHT ESPECIALLY ACROSS OUR SOUTH AND THIS SHOULD BE ENOUGH TO
LIMIT ANY FOG THERE. ACROSS OUR NORTH AND NE WINDS SHOULD REMAIN
LIGHT AND WILL MENTION PATCHY FOG THAT AREA LATE TONIGHT. ALSO WITH
CLEAR SKIES TEMPERATURES DROPPED A LITTLE COOLER THAN MET/MAV BLEND
IN THE AREAS WITH LIGHT OR NO WINDS.

MILD AND UNEVENTFUL WEATHER WILL BE THE RULE SUNDAY.  MOST MODELS
STILL KEEP PRECIP SOUTH OF OUR REGION AS THE UPPER LOW MOVES EAST
ALONG THE GULF COAST STATES.  WE WILL PROBABLY SEE INCREASING MID
AND HIGH CLOUDS LATE SUNDAY INTO MONDAY.

THE NAM/GFS/GEM AND EUROPEAN BRING THE NEXT COLD FRONT TO THE
ILLINOIS BORDER BY 00Z WEDNESDAY AND THEN ACROSS OUR AREA TUESDAY
EVENING.  WILL DROP MENTION OF ANY RAIN CHANCES ACROSS OUR EASTERN
HALF TUESDAY MORNING AS MODELS KEEP ALL PRECIP CLOSER TO FRONT.

LIGHT PRECIP STILL LOOKS POSSIBLE WEDNESDAY AND THURSDAY AS THE
UPPER LOW DEEPENS OVER THE UPPER MIDWEST AND THEN MOVES EAST ACROSS
THE SOUTHERN GREAT LAKES ON THURSDAY. THERE ARE STILL MINOR
DISAGREEMENTS BETWEEN MODELS ON COLD IT WILL GET.  MOST MODELS SHOW
LOW LEVEL THICKNESS COLD ENOUGH FOR AT LEAST MIXED RAIN AND SNOW BY
THURSDAY.  SO WILL CONTINUE LOW CHANCES OF RAIN AND SNOW SHOWERS.

DRY WEATHER WILL BE THE RULE FRIDAY AND SATURDAY AS THE UPPER LOW
CONTINUES MOVING EAST.  MODELS BUILD A WEAK UPPER RIDGE INTO THE
MISSISSIPPI VALLEY BY SATURDAY.

AS FAR AS TEMPERATURES ARE CONCERNED WENT A LITTLE LOWER THAN
MAV/MET BLEND AS SKIES WILL BE CLEAR AND WINDS WILL BE LIGHT
ESPECIALLY ACROSS OUR NORTH AND NORTHEAST.  DID NOT MAKE ANY
SIGNIFICANT CHANGES TO MOST OTHER PERIODS.  BUT I WENT A LITTLE
COOLER THAN HPC AROUND THANKSGIVING DAY AS THE UPPER LOW MOVES BY
AND MOST MODELS INDICATE THIS PERIOD IS WHEN THE COLDEST AIR WILL BE
MOVING ACROSS OUR REGION.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH
UPDATE...TDUD

000
FXUS63 KIWX 212330
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
630 PM EST SAT NOV 21 2009

.AVIATION...
HIGH PRESSURE CENTERED OVER EASTERN GREAT LAKES WILL BRING CLEAR
SKIES AND LIGHT WINDS TO THE REGION THIS TAF PERIOD. WILL GO WITH
PERSISTENCE FORECAST IN ANTICIPATION OF FOG REDEVELOPING OVERNIGHT
AT BOTH TAF SITES OTHERWISE VFR CONDITIONS PREVAIL.

&&

.SHORT TERM...
UPPER RIDGE IS BUILDING OVER THE CWA THIS AFTERNOON AS SFC
RIDGING SLIDES SLOWLY EAST RESULTING IN A SUNNY DAY FOR MOST AS AN
AREA OF LATENT STRATUS CLOUDS DISSOLVES OVER SOUTH CENTRAL
COUNTIES. SIGNIFICANT MORNING FOG DEVELOPED UPSTREAM IN THE
ENVIRONMENT THAT WILL TRANSLATE OVERHEAD BY MORNING BRINGING A
REPEAT OF FOGGY CONDITIONS INTO MID/LATE MORNING AS MOSTLY CLEAR
SKIES AND LIGHT WINDS ON WEST SIDE OF DEPARTING SFC RIDGE ALLOWS
EFFECTIVE COOLING WHILE LLEVEL MOISTURE REMAINS IN PLACE PER TIME
HEIGHTS.

ON SUNDAY SUNSHINE WILL AGAIN MAKE ITS PRESENCE FELT ONCE MORNING
FOG/LOW STRATUS MIXES OUT THOUGH AS WITH TODAY SOME LOCATIONS MAY
NOT CLEAR OUT UNTIL MID TO LATE MORNING. TOMORROW AFTERNOON WILL
BE A BIT WARMER THAN TODAY AS TEMPS ALOFT AT H92 RISE A BIT WITH
SOUTHERLY FLOW DEVELOPING IN EARNEST TO JUST TO OUR WEST ON THE
BACK SIDE OF RETREATING LLEVEL RIDGE. ADEQUATE MIXING WOULD SEE
HIGHS REACH THE MID TO UPPER 50S WHICH IS IN LINE WITH A MET/MAV
GUIDANCE BLEND AND VERY SIMILAR TO INHERITED FORECAST.

BY MONDAY NIGHT DEEPER MOISTURE BEINGS TO ENCROACH FROM THE SOUTH
AHEAD OF WAVE LIFTING AWAY FROM THE GULF COAST WITH INCREASING
GRADIENT FLOW...SO WILL HOLD OFF ON ANY ADDITIONAL FOG MENTION FOR
MONDAY NIGHT AT THIS POINT WITH SLIGHTLY MILDER LOW TEMPS.

 &&

.LONG TERM...
MED RANGE GUIDANCE IN GOOD AGREEMENT INTO LT WEEK BFR DEPARTING WAYS
NXT WEEKEND. PARADE OF SW TROUGHS EMBEDDED WITHIN PERTURBED HIGH
MOMENTUM FLW ACRS THE NRN PACIFIC PROMISE AN UNSETTLED END TO
NOVEMBER. LEAD SW INTO THE SW US WILL DO LTL OTHER THAN DISLODGE
INTENSE SRN STREAM SW OVR LA SHRT TERM. MORE POTENT WAVE OUT NR 140W
WILL DIG INLAND SUN AND EMERGE OVR THE CNTRL PLAINS MON. CONTD
INTENSIFICATION SHLD LEAD TO A DECENT FNTL RAIN BAND TUE ALTHOUGH
STREAM SEPARATION AND WK MID LVL RIDGING ACRS THE GOMEX SUGGEST NO
SIG LL MSTR ENTRAINMENT INTO THIS SYS AND WILL CONT TO RIDE LOW CHC
POPS. MORE SUBSTANTIAL AMPLIFICATION UPSTREAM OF THIS SYS TIED TO
MORE SIG LW TROUGHING DVLPG ACRS THE NEPAC LT WEEK ALLOWS SECONDARY
FOLLOWING WAVE TO REINFORCE DEEPENING GREAT LAKES TROUGH AND FAIRLY
IMPRESSIVE SURGE OF COLD AIR THU/FRI WHICH LOOKS FVRBL FOR CONTD
RAIN/SNOW MENTION ALTHOUGH 12Z GUIDANCE WOULD BODILY FVR A BTR CHC
OF RAIN W/BNDRY LYR LOOKING A BIT TOO WARM.

OTHERWISE TEMPS NR NORMAL TO START...TAILING OFF TO BLO NORMAL BY
THANKSGIVING AND INTO NXT WEEKEND.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUD
LONG TERM...HOLSTEN
AVIATION...LUD

000
FXUS63 KIND 212300
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
600 PM EST SAT NOV 21 2009

.AVIATION DISCUSSION...FOR THE 00Z TAFS
VFR CONDITIONS THROUGH THE TAF PERIOD. HIGH PRESSURE WILL BE THE
MAIN WEATHER SYSTEM CONTROLLING INDIANAS WEATHER. DRYING OF SURFACE
DURING THE PAST 2 DAYS WILL LIMIT FOG DEVELOPMENT. DUE TO THE CLEAR
SKIES AND CALM WINDS THERE MAY BE SOME AREAS OF MVFR VISIBILITIES
AROUND SUNRISE. INCLUDED THIS IN ALL BUT IND TAF. THERE SHOULD BE
MIXING DUE TO THE CITY TO KEEP VISIBILITIES VFR. A WARM FRONT WILL
MOVE INTO KENTUCKY SUNDAY AFTERNOON. DUE TO THE LACK OF MOISTURE
ONLY EFFECT WILL BE SOME HIGH CLOUDS.

&&

.DISCUSSION...
QUIET WEATHER WAS THE RULE AS HIGH PRESSURE WAS CENTERED OVER THE
EASTERN GREAT LAKES AND OHIO. VISIBLE SATELLITE SHOWED PATCHY LOW
CLOUDS ACROSS OUR FAR NORTHEAST. OTHERWISE SKIES WERE MOSTLY CLEAR
ACROSS OUR REGION.  WATER VAPOR IR SHOWED A WEAK UPPER TROUGH OVER
THE ST. LAWRENCE VALLEY AND UPPER LOW OVER EAST TEXAS AND AN UPPER
RIDGE FROM THE CENTRAL PLAINS TO LAKE SUPERIOR.

MAIN FORECAST CHALLENGES ARE WHETHER TO MENTION ANY PATCHY FOG LATE
TONIGHT. RAIN CHANCES EARLY TO MIDDLE OF NEXT WEEK AND PRECIPITATION
CHANCES AND TYPE AROUND THANKSGIVING.

CONCERNING FOG TONIGHT...DEWPOINTS ARE PRESENTLY HIGHER THAN
FORETASTED LOWS.  ON THE OTHER HAND MODELS BRING SOME SLIGHTLY DRIER
AIR IN LATER TONIGHT. NAM SHOWS A WEAK ESE GRADIENT DEVELOPING
OVERNIGHT ESPECIALLY ACROSS OUR SOUTH AND THIS SHOULD BE ENOUGH TO
LIMIT ANY FOG THERE. ACROSS OUR NORTH AND NE WINDS SHOULD REMAIN
LIGHT AND WILL MENTION PATCHY FOG THAT AREA LATE TONIGHT. ALSO WITH
CLEAR SKIES TEMPERATURES DROPPED A LITTLE COOLER THAN MET/MAV BLEND
IN THE AREAS WITH LIGHT OR NO WINDS.

MILD AND UNEVENTFUL WEATHER WILL BE THE RULE SUNDAY.  MOST MODELS
STILL KEEP PRECIP SOUTH OF OUR REGION AS THE UPPER LOW MOVES EAST
ALONG THE GULF COAST STATES.  WE WILL PROBABLY SEE INCREASING MID
AND HIGH CLOUDS LATE SUNDAY INTO MONDAY.

THE NAM/GFS/GEM AND EUROPEAN BRING THE NEXT COLD FRONT TO THE
ILLINOIS BORDER BY 00Z WEDNESDAY AND THEN ACROSS OUR AREA TUESDAY
EVENING.  WILL DROP MENTION OF ANY RAIN CHANCES ACROSS OUR EASTERN
HALF TUESDAY MORNING AS MODELS KEEP ALL PRECIP CLOSER TO FRONT.

LIGHT PRECIP STILL LOOKS POSSIBLE WEDNESDAY AND THURSDAY AS THE
UPPER LOW DEEPENS OVER THE UPPER MIDWEST AND THEN MOVES EAST ACROSS
THE SOUTHERN GREAT LAKES ON THURSDAY. THERE ARE STILL MINOR
DISAGREEMENTS BETWEEN MODELS ON COLD IT WILL GET.  MOST MODELS SHOW
LOW LEVEL THICKNESS COLD ENOUGH FOR AT LEAST MIXED RAIN AND SNOW BY
THURSDAY.  SO WILL CONTINUE LOW CHANCES OF RAIN AND SNOW SHOWERS.

DRY WEATHER WILL BE THE RULE FRIDAY AND SATURDAY AS THE UPPER LOW
CONTINUES MOVING EAST.  MODELS BUILD A WEAK UPPER RIDGE INTO THE
MISSISSIPPI VALLEY BY SATURDAY.

AS FAR AS TEMPERATURES ARE CONCERNED WENT A LITTLE LOWER THAN
MAV/MET BLEND AS SKIES WILL BE CLEAR AND WINDS WILL BE LIGHT
ESPECIALLY ACROSS OUR NORTH AND NORTHEAST.  DID NOT MAKE ANY
SIGNIFICANT CHANGES TO MOST OTHER PERIODS.  BUT I WENT A LITTLE
COOLER THAN HPC AROUND THANKSGIVING DAY AS THE UPPER LOW MOVES BY
AND MOST MODELS INDICATE THIS PERIOD IS WHEN THE COLDEST AIR WILL BE
MOVING ACROSS OUR REGION.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH

000
FXUS63 KIND 212038
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
335 PM EST SAT NOV 21 2009

.DISCUSSION...
QUIET WEATHER WAS THE RULE AS HIGH PRESSURE WAS CENTERED OVER THE
EASTERN GREAT LAKES AND OHIO. VISIBLE SATELLITE SHOWED PATCHY LOW
CLOUDS ACROSS OUR FAR NORTHEAST. OTHERWISE SKIES WERE MOSTLY CLEAR
ACROSS OUR REGION.  WATER VAPOR IR SHOWED A WEAK UPPER TROUGH OVER
THE ST. LAWRENCE VALLEY AND UPPER LOW OVER EAST TEXAS AND AN UPPER
RIDGE FROM THE CENTRAL PLAINS TO LAKE SUPERIOR.

MAIN FORECAST CHALLENGES ARE WHETHER TO MENTION ANY PATCHY FOG LATE
TONIGHT. RAIN CHANCES EARLY TO MIDDLE OF NEXT WEEK AND PRECIPITATION
CHANCES AND TYPE AROUND THANKSGIVING.

CONCERNING FOG TONIGHT...DEWPOINTS ARE PRESENTLY HIGHER THAN
FORETASTED LOWS.  ON THE OTHER HAND MODELS BRING SOME SLIGHTLY DRIER
AIR IN LATER TONIGHT. NAM SHOWS A WEAK ESE GRADIENT DEVELOPING
OVERNIGHT ESPECIALLY ACROSS OUR SOUTH AND THIS SHOULD BE ENOUGH TO
LIMIT ANY FOG THERE. ACROSS OUR NORTH AND NE WINDS SHOULD REMAIN
LIGHT AND WILL MENTION PATCHY FOG THAT AREA LATE TONIGHT. ALSO WITH
CLEAR SKIES TEMPERATURES DROPPED A LITTLE COOLER THAN MET/MAV BLEND
IN THE AREAS WITH LIGHT OR NO WINDS.

MILD AND UNEVENTFUL WEATHER WILL BE THE RULE SUNDAY.  MOST MODELS
STILL KEEP PRECIP SOUTH OF OUR REGION AS THE UPPER LOW MOVES EAST
ALONG THE GULF COAST STATES.  WE WILL PROBABLY SEE INCREASING MID
AND HIGH CLOUDS LATE SUNDAY INTO MONDAY.

THE NAM/GFS/GEM AND EUROPEAN BRING THE NEXT COLD FRONT TO THE
ILLINOIS BORDER BY 00Z WEDNESDAY AND THEN ACROSS OUR AREA TUESDAY
EVENING.  WILL DROP MENTION OF ANY RAIN CHANCES ACROSS OUR EASTERN
HALF TUESDAY MORNING AS MODELS KEEP ALL PRECIP CLOSER TO FRONT.

LIGHT PRECIP STILL LOOKS POSSIBLE WEDNESDAY AND THURSDAY AS THE
UPPER LOW DEEPENS OVER THE UPPER MIDWEST AND THEN MOVES EAST ACROSS
THE SOUTHERN GREAT LAKES ON THURSDAY. THERE ARE STILL MINOR
DISAGREEMENTS BETWEEN MODELS ON COLD IT WILL GET.  MOST MODELS SHOW
LOW LEVEL THICKNESS COLD ENOUGH FOR AT LEAST MIXED RAIN AND SNOW BY
THURSDAY.  SO WILL CONTINUE LOW CHANCES OF RAIN AND SNOW SHOWERS.

DRY WEATHER WILL BE THE RULE FRIDAY AND SATURDAY AS THE UPPER LOW
CONTINUES MOVING EAST.  MODELS BUILD A WEAK UPPER RIDGE INTO THE
MISSISSIPPI VALLEY BY SATURDAY.

AS FAR AS TEMPERATURES ARE CONCERNED WENT A LITTLE LOWER THAN
MAV/MET BLEND AS SKIES WILL BE CLEAR AND WINDS WILL BE LIGHT
ESPECIALLY ACROSS OUR NORTH AND NORTHEAST.  DID NOT MAKE ANY
SIGNIFICANT CHANGES TO MOST OTHER PERIODS.  BUT I WENT A LITTLE
COOLER THAN HPC AROUND THANKSGIVING DAY AS THE UPPER LOW MOVES BY
AND MOST MODELS INDICATE THIS PERIOD IS WHEN THE COLDEST AIR WILL BE
MOVING ACROSS OUR REGION.

&&

.AVIATION...DISCUSSION FOR 21/18Z TAFS

HIGH PRESSURE WILL PROVIDE A DRY EASTERLY FLOW WHICH SHOULD KEEP
MOST CLOUDS AT BAY DURING THE FIRST HALF OF THE PERIOD...WITH MAINLY
HIGH CLOUDS INCREASING ON SUNDAY.

PROBLEM IS POTENTIAL FOR MORE FOG TONIGHT. FORECASTED LOWS ARE BELOW
AFTERNOON DEWPOINTS...BUT SLIGHTLY DRIER AIR WILL BE WORKING IN
OVERNIGHT. WITH LIGHT WINDS OVERNIGHT THOUGH...FEEL THAT ODDS FOR
FOG DEVELOPMENT ARE HIGH ENOUGH TO PUT MVFR FOG IN AT MOST SITES
NEAR SUNRISE. EAST WINDS SHOULD PROHIBIT FOG FORMATION AT IND DUE TO
INFLUENCE OF CITY. ANY FOG WILL BURN OFF QUICKLY SUN MORNING.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...CS

000
FXUS63 KIWX 212025
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
325 PM EST SAT NOV 21 2009

.SHORT TERM...
UPPER RIDGE IS BUILDING OVER THE CWA THIS AFTERNOON AS SFC
RIDGING SLIDES SLOWLY EAST RESULTING IN A SUNNY DAY FOR MOST AS AN
AREA OF LATENT STRATUS CLOUDS DISSOLVES OVER SOUTH CENTRAL
COUNTIES. SIGNIFICANT MORNING FOG DEVELOPED UPSTREAM IN THE
ENVIRONMENT THAT WILL TRANSLATE OVERHEAD BY MORNING BRINGING A
REPEAT OF FOGGY CONDITIONS INTO MID/LATE MORNING AS MOSTLY CLEAR
SKIES AND LIGHT WINDS ON WEST SIDE OF DEPARTING SFC RIDGE ALLOWS
EFFECTIVE COOLING WHILE LLEVEL MOISTURE REMAINS IN PLACE PER TIME
HEIGHTS.

ON SUNDAY SUNSHINE WILL AGAIN MAKE ITS PRESENCE FELT ONCE MORNING
FOG/LOW STRATUS MIXES OUT THOUGH AS WITH TODAY SOME LOCATIONS MAY
NOT CLEAR OUT UNTIL MID TO LATE MORNING. TOMORROW AFTERNOON WILL
BE A BIT WARMER THAN TODAY AS TEMPS ALOFT AT H92 RISE A BIT WITH
SOUTHERLY FLOW DEVELOPING IN EARNEST TO JUST TO OUR WEST ON THE
BACK SIDE OF RETREATING LLEVEL RIDGE. ADEQUATE MIXING WOULD SEE
HIGHS REACH THE MID TO UPPER 50S WHICH IS IN LINE WITH A MET/MAV
GUIDANCE BLEND AND VERY SIMILAR TO INHERITED FORECAST.

BY MONDAY NIGHT DEEPER MOISTURE BEINGS TO ENCROACH FROM THE SOUTH
AHEAD OF WAVE LIFTING AWAY FROM THE GULF COAST WITH INCREASING
GRADIENT FLOW...SO WILL HOLD OFF ON ANY ADDITIONAL FOG MENTION FOR
MONDAY NIGHT AT THIS POINT WITH SLIGHTLY MILDER LOW TEMPS.

 &&

.LONG TERM...
MED RANGE GUIDANCE IN GOOD AGREEMENT INTO LT WEEK BFR DEPARTING WAYS
NXT WEEKEND. PARADE OF SW TROUGHS EMBEDDED WITHIN PERTURBED HIGH
MOMENTUM FLW ACRS THE NRN PACIFIC PROMISE AN UNSETTLED END TO
NOVEMBER. LEAD SW INTO THE SW US WILL DO LTL OTHER THAN DISLODGE
INTENSE SRN STREAM SW OVR LA SHRT TERM. MORE POTENT WAVE OUT NR 140W
WILL DIG INLAND SUN AND EMERGE OVR THE CNTRL PLAINS MON. CONTD
INTENSIFICATION SHLD LEAD TO A DECENT FNTL RAIN BAND TUE ALTHOUGH
STREAM SEPARATION AND WK MID LVL RIDGING ACRS THE GOMEX SUGGEST NO
SIG LL MSTR ENTRAINMENT INTO THIS SYS AND WILL CONT TO RIDE LOW CHC
POPS. MORE SUBSTANTIAL AMPLIFICATION UPSTREAM OF THIS SYS TIED TO
MORE SIG LW TROUGHING DVLPG ACRS THE NEPAC LT WEEK ALLOWS SECONDARY
FOLLOWING WAVE TO REINFORCE DEEPENING GREAT LAKES TROUGH AND FAIRLY
IMPRESSIVE SURGE OF COLD AIR THU/FRI WHICH LOOKS FVRBL FOR CONTD
RAIN/SNOW MENTION ALTHOUGH 12Z GUIDANCE WOULD BODILY FVR A BTR CHC
OF RAIN W/BNDRY LYR LOOKING A BIT TOO WARM.

OTHERWISE TEMPS NR NORMAL TO START...TAILING OFF TO BLO NORMAL BY
THANKSGIVING AND INTO NXT WEEKEND.

&&

.AVIATION...
MAIN CONCERN IN TAF IS REPEAT OF MORNING FOG YET AGAIN SUNDAY
MORNING AS LIGHT WINDS AND CLEAR SKIES ARE EXPECTED AGAIN.
OTHERWISE...AS AREA OF LOW STRATUS CONTINUES TO DISSOLVE THIS AFT
TERMINALS SHOULD REMAIN VFR INTO TONIGHT AND RETURN AFTER MORNING
FOG LIFTS.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUD
LONG TERM...HOLSTEN
AVIATION...LUD

000
FXUS63 KIWX 211757
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1257 PM EST SAT NOV 21 2009

.AVIATION...
MAIN CONCERN IN TAF IS REPEAT OF MORNING FOG YET AGAIN SUNDAY
MORNING AS LIGHT WINDS AND CLEAR SKIES ARE EXPECTED AGAIN.
OTHERWISE...AS AREA OF LOW STRATUS CONTINUES TO DISSOLVE THIS AFT
TERMINALS SHOULD REMAIN VFR INTO TONIGHT AND RETURN AFTER MORNING
FOG LIFTS.

&&

.PREV DISCUSSION... /ISSUED 630 AM EST SAT NOV 21 2009/

SHORT TERM...

..TODAY THROUGH SUNDAY NIGHT...

HIGH PRESSURE WAS ACROSS MOST OF AREA EARLY THIS MORNING WHILE AN
UPPER LEVEL TROUGH WAS MOVING THROUGH. LITTLE SURFACE REFLECTION
FROM THE TROUGH BUT CLOUDS WERE HANGING IN ACROSS THE FAR NORTH AND
NORTHEAST AHEAD OF THIS FEATURE. MEANWHILE...AREA OF STRATOCUMULUS
CLOUDS THAT FORMED LAST NIGHT IN IL AND PERSISTED THROUGH THE DAY
HAVE DRIFTED INTO OUR SOUTHWEST COUNTIES. SATELLITE FOG PRODUCT
SHOWS THIS AREA SLOWLY EXPANDING AND DRIFTING EAST. FORECAST
CHALLENGES CONTINUE TO BE CLOUD COVER...TEMPS AND FOG POSSIBILITY IN
THE SHORT TERM PERIOD.

WITH WEAK HIGH PRESSURE AND SUBSIDENCE TODAY EXPECT A GRADUAL
DECREASE IN OVERALL CLOUDINESS THROUGH THE DAY. CLOUDS ACROSS NORTH
AND NORTHEAST SHOULD GRADUALLY DISSIPATE/EXIT OUR AREA BEHIND THE
DEPARTING TROUGH THIS AFTERNOON. A LITTLE CONCERNED WITH THE CLOUDS
IN THE SOUTHWEST THOUGH AS THEY PERSISTED YESTERDAY AND DID NOT MIX
OUT. IT IS POSSIBLE A SIMILAR SITUATION COULD OCCUR AGAIN TODAY.
WILL BE OPTIMISTIC WITH A GRADUAL ERODING OF THESE CLOUDS.
TEMPERATURES SHOULD BE VERY SIMILAR TO FRIDAY READINGS WITH SIMILAR
AIRMASS.

DRYING CONTINUES TONIGHT WITH CONTINUED SUBSIDENCE AS MID LEVEL
RIDGE NOSES INTO THE AREA. SHOULD SEE MOSTLY CLEAR SKIES AND LIGHT
WINDS EARLY WHICH SHOULD SET THE STAGE FOR FOG FORMATION LATE. SETUP
LOOKS A LITTLE BETTER THAN THIS MORNING AS RIDGE WILL BE BUILDING IN
AND DENSE FOG ALREADY FORMING TO OUR WEST NEAR THIS RIDGING THIS
MORNING.

FOG MAY TAKE SOME TIME TO BURN OFF SUNDAY MORNING BUT ONCE IT DOES
SHOULD BE ANOTHER NICE LATE NOVEMBER DAY WITH HIGHS INTO THE 50S.
CONTINUED TO BE A LITTLE CONSERVATIVE WITH POSSIBLE FOG AND STRATUS
IN THE MORNING HOURS INHIBITING TEMPERATURE RISE. FEEL FOG COULD
FORM YET AGAIN SUNDAY NIGHT AS HIGH SLIDES EAST BUT THERE MAY BE
ENOUGH GRADIENT WIND TO PRECLUDE WIDESPREAD FOG. WILL LIKELY HOLD
OFF ON ANY MENTION IN THIS PERIOD.

LONG TERM /MONDAY THROUGH FRIDAY/...

MSTR WILL BE WORKING NORTH AT THE START OF THE PERIOD...BUT RH
PROFILES SUGGEST SKIES SHOULD STILL GENERALLY BE PARTLY TO MOSTLY
SUNNY WITH SOME HIGH CLOUDS. THIS WILL RESULT IN HIGHS LIKELY BEING
A FEW DEGREES WARMER THAN PREVIOUSLY THOUGHT SO HAVE BROUGHT UP A
BIT BUT HOLDING SHY OF ENSEMBLE AND MET GUIDANCE IN THE MID
50S...WHICH IS STILL ENTIRELY POSSIBLE WITH SLOWER SOLUTIONS FOR THE
SYSTEM TO THE WEST.

A BIT OF AGREEMENT ON TIMING OF THE INITIAL LOW APPROACHING THE AREA
IS ATTEMPTING TO OCCUR. AT THIS POINT...INCREASING CHANCES THAT
MONDAY NIGHT AND MAYBE EVEN THE FIRST PART OF TUESDAY MAY END UP
DRY. ENOUGH CONFIDENCE IN TRENDS TO REMOVE POPS MON EVE BUT LEAVE
UNTOUCHED LATE MON NGT THROUGH MUCH OF THE REMAINDER OF THE PERIOD.
MORE THAN LIKELY POPS WILL BE REMOVED ENTIRELY FOR REMAINDER OF
MONDAY NIGHT IN FUTURE FORECASTS. WHERE THE CHALLENGES REMAIN IS HOW
MUCH COLD AIR ARRIVES AND HOW LONG IT STICKS AROUND. 00Z OPER GFS
CONTINUES TO BRING SHOT OF -3 TO -5 C 850 MB TEMPS IN BY WEDS BUT
HAS NOW BACKED OFF ON THE MUCH COLDER SCENARIO WITH NEXT PUSH OF
COLDEST AIR...STILL ONLY AS LOW AS -6 C...PASSING BY TO THE SW. THIS
WOULD RESULT IN THE POTENTIAL FOR RAIN OR SNOW MIXED. 00Z ECMWF
PAINTS A DIFFERENT PICTURE WITH THE LOW MOVING TO THE NW SLOWER THAN
THE GFS AND THE COLDEST AIR NOT ARRIVING TILL MAINLY THURSDAY. GFS
ENSEMBLE SEEMS TO BE MIDDLE OF THE ROAD WITH PROGRESS OF SYSTEM WITH
MOST FAVORABLE TIME FRAME STILL IN THE WEDS/WEDS NGT PERIOD FOLLOWED
BY A PUSH OF COOLER AIR. WITH SO MANY QUESTIONS IN TERMS OF THERMAL
FIELDS AND TIMING...WILL LEAVE TEMPS AND PRECIP TYPES ALONE THROUGH
THE REMAINDER OF THE PERIOD WITH ANY CHANGES MADE NOW LIKELY HAVING
TO BE MODIFIED ONCE AGAIN...POTENTIAL FLIP FLOPPING. IF MODELS ARE
TO BE BELIEVED AFTER THIS SYSTEM MOVES BY...A QUICK MODERATION COULD
OCCUR WITH 00Z ECMWF SHOWING SURGE OF WELL ABOVE ZERO 850 MB TEMPS
FOR THE HOLIDAY WEEKEND AND GFS NOT TOO FAR OFF.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LUD

000
FXUS63 KIND 211623
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1123 AM EST SAT NOV 21 2009

.AVIATION...DISCUSSION FOR 21/18Z TAFS

HIGH PRESSURE WILL PROVIDE A DRY EASTERLY FLOW WHICH SHOULD KEEP
MOST CLOUDS AT BAY DURING THE FIRST HALF OF THE PERIOD...WITH MAINLY
HIGH CLOUDS INCREASING ON SUNDAY.

PROBLEM IS POTENTIAL FOR MORE FOG TONIGHT. FORECASTED LOWS ARE BELOW
AFTERNOON DEWPOINTS...BUT SLIGHTLY DRIER AIR WILL BE WORKING IN
OVERNIGHT. WITH LIGHT WINDS OVERNIGHT THOUGH...FEEL THAT ODDS FOR
FOG DEVELOPMENT ARE HIGH ENOUGH TO PUT MVFR FOG IN AT MOST SITES
NEAR SUNRISE. EAST WINDS SHOULD PROHIBIT FOG FORMATION AT IND DUE TO
INFLUENCE OF CITY. ANY FOG WILL BURN OFF QUICKLY SUN MORNING.

&&

.UPDATE...FOR REST OF TODAY...
UPDATED FORECAST TO REMOVE MENTION OF FOG.  ALSO AREA OF LOW CLOUDS
ALONG AND NORTH OF A KDVN-KGEZ LINE WAS CLEARING FROM THE SOUTH AND
MOST IF NOT ALL OF OUR FORECAST AREA WILL BE MOSTLY SUNNY BY MID DAY.
RUC SOUNDING SHOWS LITTLE IN THE WAY OF CLOUDS REST OF TODAY. NO
SIGNFICANT CHANGES MADE TO TEMPERATURES FOR TODAY.

&&

.DISCUSSION...
QUIET MORNING IN PROGRESS AS SURFACE HIGH PRESSURE IS CENTERED OVER
EASTERN OHIO. WEAK UPPER LEVEL SHORTWAVE TRAVERSING THE REGION EARLY
THIS MORNING. AREA OF STRATOCUMULUS HAD DEVELOPED OVER NORTHERN HALF
OF THE FORECAST AREA AND WILL LIKELY SLIP INTO THE INDY METRO DURING
THE PREDAWN HOURS. WHERE SKIES WERE MAINLY CLEAR...PATCHY MIST/FOG
HAD DEVELOPED AGAIN THIS MORNING. TEMPERATURES AT 08Z WERE IN THE
30S.

FORECAST CHALLENGES TODAY FOCUS ON CLOUDS THIS MORNING...
TEMPERATURES THROUGH MONDAY...AND TRANSITION TO COLDER AND MORE
UNSETTLED PATTERN BY MIDWEEK. MODELS IN EXCELLENT AGREEMENT WITH
REGARDS TO SENSIBLE WEATHER TODAY AND SUNDAY.

AFOREMENTIONED SHORTWAVE WILL CONTINUE TO PROGRESS EAST THROUGH THE
MORNING AS HIGH REMAINS FIRMLY ENTRENCHED AT THE SURFACE. EXPECT
LOWER CLOUDS TO PERSIST THROUGH DAYBREAK ACROSS NORTHERN COUNTIES
WITH MOSTLY CLEAR SKIES ELSEWHERE. AS THE SHORTWAVE ENERGY SHIFTS
EAST INTO OHIO BY LATE MORNING HOWEVER...DO ANTICIPATE A DECREASE IN
STRATOCUMULUS COVERAGE WITH PLENTY OF SUNSHINE PROVIDING FOR YET
ANOTHER IDEAL SATURDAY IN NOVEMBER. RIDGING ALOFT WILL DEVELOP THIS
AFTERNOON AND TONIGHT ACROSS THE REGION. OTHER THAN CIRRUS SHIELD
PASSING BY TO THE SOUTHEAST IN ASSOCIATION WITH LOW PRESSURE LIFTING
OUT OF THE NORTHERN GULF COAST...SKIES WILL REMAIN GENERALLY CLEAR.

MODEL CONSENSUS CONTINUES TO TREND AWAY FROM CENTRAL INDIANA SEEING
ANY SIGNIFICANT IMPACT FROM SAID LOW PRESSURE ALONG THE GULF COAST
ON SUNDAY. HIGH PRESSURE RIDGE AT THE SURFACE EXTENDING FROM NEW
ENGLAND SOUTHWEST BACK INTO THE OHIO VALLEY WILL KEEP THIS LOW FROM
TAKING A MORE NORTHERLY TRACK INTO THE TENNESSEE VALLEY...AND
CONSEQUENTLY PROVIDE A VERY PLEASANT SUNDAY FOR THE THIRD STRAIGHT
WEEK. THE ONLY IMPACTS SHOULD BE A SUBTLE INCREASE IN MID AND HIGH
LEVEL CLOUDS INTO THE REGION FROM THE SOUTHEAST SUNDAY AFTERNOON AND
NIGHT. MORE SIGNIFICANT 285-300K ISENTROPIC LIFT ON BOTH NAM/OP GFS
NOW REMAIN WELL DISPLACED TO THE SOUTHEAST OF THE FORECAST AREA.
CONSIDERING A PREDOMINANT EASTERLY FLOW IN THE LOWER LEVELS KEEPING
BOUNDARY LAYER FAIRLY DRY...FEEL CONFIDENT IN REMOVING 20 POPS FROM
SUNDAY NIGHT FORECAST. SKIES MAY ACTUALLY END UP BEING MOSTLY CLEAR
NORTHWEST OF THE INDY METRO.

WEAKENING UPPER LOW ASSOCIATED WITH THE GULF COAST LOW WILL BECOME
ABSORBED BY SIGNIFICANT UPPER TROUGH AS IT BECOMES WELL ESTABLISHED
OVER THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THE AMPLIFICATION OF
THE TROUGH WILL SPARK DEVELOPMENT OF LOW PRESSURE AND A COLD FRONT
MONDAY NIGHT. SPECIFIC MODELS DIFFER ON HOW FAST THE LOW PRESSURE
WAVE SPINS UP AND ITS LOCATION BY TUESDAY MORNING. FAVOR MORE
CONSERVATIVE AND SLOWER 00Z NAM/ECMWF SOLUTION...WITH THE LOW
PRESSURE NEAR KANSAS CITY BY TUESDAY MORNING. 00Z OP GFS/GEM/GFS
ENSEMBLE MEAN BREAK DOWN HIGH PRESSURE OFF THE CANADIAN MARITIMES
FASTER AND CONSEQUENTLY PROGRESS THE LOW AND FRONT FURTHER EAST.
WARM FRONT LIFTS NORTH ACROSS THE FORECAST AREA BY MONDAY NIGHT WITH
SOUTHERLY FLOW DEVELOPING OUT AHEAD OF THE APPROACHING COLD FRONT.
LIKELY TO SEE AN INCREASE IN MID LEVEL CLOUDS AS DEEPER MOISTURE IN
ADVECTS INTO CENTRAL INDIANA MONDAY AFTERNOON AND NIGHT IN THE
VICINITY OF THE WARM FRONT.

ADJUSTED RAIN CHANCES FOR TUESDAY AS COLD FRONT LIKELY TO NOT ARRIVE
UNTIL LATE TUESDAY...POSSIBLY EVEN TUESDAY NIGHT SHOULD THE 00Z
ECMWF SOLUTION BE REALIZED. WITH UNCERTAINTY OF THE TIMING OF THE
FRONTAL PASSAGE...WILL CONTINUE WITH JUST A MENTION OF RAIN IN THE
FORECAST TUESDAY NIGHT. OP GFS/ECMWF BOTH DROPPING LOW LEVEL
THICKNESSES TOWARDS CRITICAL VALUES NEEDED FOR A FEW WET SNOWFLAKES
TO MIX IN BY EARLY WEDNESDAY. THE PASSAGE OF THE COLD FRONT WILL
SIGNAL A CHANGE TO A MORE UNSETTLED AND COLDER REGIME FOR THE REGION
FOR THE SECOND HALF OF THE UPCOMING WEEK. WITH UPPER LEVEL LOW
PROGRESSING SLOWLY ACROSS THE LOWER GREAT LAKES WEDNESDAY AND
THURSDAY...LOWER LEVELS DO APPEAR TO BECOME SUFFICIENTLY COLD ENOUGH
FOR A FEW SNOW SHOWERS...ESPECIALLY WEDNESDAY NIGHT AND THANKSGIVING
DAY. WILL CONTINUE WITH LOW CHANCES FOR RAIN/SNOW SHOWERS THROUGH
THE PERIOD.

TEMPS...TRENDED TOWARDS WARMER MAVMOS GUIDANCE FOR HIGHS TODAY AND
SUNDAY. ANALYSIS OF LOW LEVEL THICKNESSES SUPPORTED LEANING TOWARDS
WARMER METMOS GUIDANCE FOR MONDAY. HIGHS IN THE MID AND UPPER 50S
WILL BE COMMONPLACE OVER THE NEXT THREE DAYS. STAYED CLOSE TO MOS
GUIDANCE FOR LOWS...WITH MID AND UPPER 30S LARGELY EXPECTED TONIGHT
AND SUNDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...CS
UPDATE...JH

000
FXUS63 KIND 211428 AAA
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
930 AM EST SAT NOV 21 2009

.UPDATE FOR REST OF TODAY...
UPDATED FORECAST TO REMOVE MENTION OF FOG.  ALSO AREA OF LOW CLOUDS
ALONG AND NORTH OF A KDVN-KGEZ LINE WAS CLEARING FROM THE SOUTH AND
MOST IF NOT ALL OF OUR FORECAST AREA WILL BE MOSTLY SUNNY BY MID DAY.
RUC SOUNDING SHOWS LITTLE IN THE WAY OF CLOUDS REST OF TODAY. NO
SIGNFICANT CHANGES MADE TO TEMPERATURES FOR TODAY.

&&

.AVIATION...DISCUSSION FOR 211200Z TAF ISSUANCE. AREAS OF IFR/LIFR
IN FOG CURRENTLY OVER THE SOUTHERN SECTIONS OF THE STATE...
OCCASIONALLY AFFECTING THE KHUF/KBMG TERMINALS. MOISTURE LAYER IS
QUITE SHALLOW...SO THESE CONDITIONS SHOULD MIX OUT FAIRLY RAPIDLY
AFTER SUNRISE...BY 211500Z.

OTHERWISE...CIGS 030-040 OVER THE NORTHERN SECTIONS OF THE LOCAL
AREA HAVE BEEN EXPANDING SLOWLY SOUTH...AFFECTING MAINLY KIND/KLAF.
210000Z UPPER AIR OBSERVATIONS INDICATE THIS MOISTURE LAYER IS QUITE
THIN AS WELL...SO EXPECTING THESE CIGS TO ERODE FROM THE EDGES AND
EVENTUALLY MIX OUT IN THE 211500Z-211700Z TIME FRAME.

SURFACE WINDS BELOW 15 KTS THROUGH 220000Z.

&&

.DISCUSSION...
QUIET MORNING IN PROGRESS AS SURFACE HIGH PRESSURE IS CENTERED OVER
EASTERN OHIO. WEAK UPPER LEVEL SHORTWAVE TRAVERSING THE REGION EARLY
THIS MORNING. AREA OF STRATOCUMULUS HAD DEVELOPED OVER NORTHERN HALF
OF THE FORECAST AREA AND WILL LIKELY SLIP INTO THE INDY METRO DURING
THE PREDAWN HOURS. WHERE SKIES WERE MAINLY CLEAR...PATCHY MIST/FOG
HAD DEVELOPED AGAIN THIS MORNING. TEMPERATURES AT 08Z WERE IN THE
30S.

FORECAST CHALLENGES TODAY FOCUS ON CLOUDS THIS MORNING...
TEMPERATURES THROUGH MONDAY...AND TRANSITION TO COLDER AND MORE
UNSETTLED PATTERN BY MIDWEEK. MODELS IN EXCELLENT AGREEMENT WITH
REGARDS TO SENSIBLE WEATHER TODAY AND SUNDAY.

AFOREMENTIONED SHORTWAVE WILL CONTINUE TO PROGRESS EAST THROUGH THE
MORNING AS HIGH REMAINS FIRMLY ENTRENCHED AT THE SURFACE. EXPECT
LOWER CLOUDS TO PERSIST THROUGH DAYBREAK ACROSS NORTHERN COUNTIES
WITH MOSTLY CLEAR SKIES ELSEWHERE. AS THE SHORTWAVE ENERGY SHIFTS
EAST INTO OHIO BY LATE MORNING HOWEVER...DO ANTICIPATE A DECREASE IN
STRATOCUMULUS COVERAGE WITH PLENTY OF SUNSHINE PROVIDING FOR YET
ANOTHER IDEAL SATURDAY IN NOVEMBER. RIDGING ALOFT WILL DEVELOP THIS
AFTERNOON AND TONIGHT ACROSS THE REGION. OTHER THAN CIRRUS SHIELD
PASSING BY TO THE SOUTHEAST IN ASSOCIATION WITH LOW PRESSURE LIFTING
OUT OF THE NORTHERN GULF COAST...SKIES WILL REMAIN GENERALLY CLEAR.

MODEL CONSENSUS CONTINUES TO TREND AWAY FROM CENTRAL INDIANA SEEING
ANY SIGNIFICANT IMPACT FROM SAID LOW PRESSURE ALONG THE GULF COAST
ON SUNDAY. HIGH PRESSURE RIDGE AT THE SURFACE EXTENDING FROM NEW
ENGLAND SOUTHWEST BACK INTO THE OHIO VALLEY WILL KEEP THIS LOW FROM
TAKING A MORE NORTHERLY TRACK INTO THE TENNESSEE VALLEY...AND
CONSEQUENTLY PROVIDE A VERY PLEASANT SUNDAY FOR THE THIRD STRAIGHT
WEEK. THE ONLY IMPACTS SHOULD BE A SUBTLE INCREASE IN MID AND HIGH
LEVEL CLOUDS INTO THE REGION FROM THE SOUTHEAST SUNDAY AFTERNOON AND
NIGHT. MORE SIGNIFICANT 285-300K ISENTROPIC LIFT ON BOTH NAM/OP GFS
NOW REMAIN WELL DISPLACED TO THE SOUTHEAST OF THE FORECAST AREA.
CONSIDERING A PREDOMINANT EASTERLY FLOW IN THE LOWER LEVELS KEEPING
BOUNDARY LAYER FAIRLY DRY...FEEL CONFIDENT IN REMOVING 20 POPS FROM
SUNDAY NIGHT FORECAST. SKIES MAY ACTUALLY END UP BEING MOSTLY CLEAR
NORTHWEST OF THE INDY METRO.

WEAKENING UPPER LOW ASSOCIATED WITH THE GULF COAST LOW WILL BECOME
ABSORBED BY SIGNIFICANT UPPER TROUGH AS IT BECOMES WELL ESTABLISHED
OVER THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THE AMPLIFICATION OF
THE TROUGH WILL SPARK DEVELOPMENT OF LOW PRESSURE AND A COLD FRONT
MONDAY NIGHT. SPECIFIC MODELS DIFFER ON HOW FAST THE LOW PRESSURE
WAVE SPINS UP AND ITS LOCATION BY TUESDAY MORNING. FAVOR MORE
CONSERVATIVE AND SLOWER 00Z NAM/ECMWF SOLUTION...WITH THE LOW
PRESSURE NEAR KANSAS CITY BY TUESDAY MORNING. 00Z OP GFS/GEM/GFS
ENSEMBLE MEAN BREAK DOWN HIGH PRESSURE OFF THE CANADIAN MARITIMES
FASTER AND CONSEQUENTLY PROGRESS THE LOW AND FRONT FURTHER EAST.
WARM FRONT LIFTS NORTH ACROSS THE FORECAST AREA BY MONDAY NIGHT WITH
SOUTHERLY FLOW DEVELOPING OUT AHEAD OF THE APPROACHING COLD FRONT.
LIKELY TO SEE AN INCREASE IN MID LEVEL CLOUDS AS DEEPER MOISTURE IN
ADVECTS INTO CENTRAL INDIANA MONDAY AFTERNOON AND NIGHT IN THE
VICINITY OF THE WARM FRONT.

ADJUSTED RAIN CHANCES FOR TUESDAY AS COLD FRONT LIKELY TO NOT ARRIVE
UNTIL LATE TUESDAY...POSSIBLY EVEN TUESDAY NIGHT SHOULD THE 00Z
ECMWF SOLUTION BE REALIZED. WITH UNCERTAINTY OF THE TIMING OF THE
FRONTAL PASSAGE...WILL CONTINUE WITH JUST A MENTION OF RAIN IN THE
FORECAST TUESDAY NIGHT. OP GFS/ECMWF BOTH DROPPING LOW LEVEL
THICKNESSES TOWARDS CRITICAL VALUES NEEDED FOR A FEW WET SNOWFLAKES
TO MIX IN BY EARLY WEDNESDAY. THE PASSAGE OF THE COLD FRONT WILL
SIGNAL A CHANGE TO A MORE UNSETTLED AND COLDER REGIME FOR THE REGION
FOR THE SECOND HALF OF THE UPCOMING WEEK. WITH UPPER LEVEL LOW
PROGRESSING SLOWLY ACROSS THE LOWER GREAT LAKES WEDNESDAY AND
THURSDAY...LOWER LEVELS DO APPEAR TO BECOME SUFFICIENTLY COLD ENOUGH
FOR A FEW SNOW SHOWERS...ESPECIALLY WEDNESDAY NIGHT AND THANKSGIVING
DAY. WILL CONTINUE WITH LOW CHANCES FOR RAIN/SNOW SHOWERS THROUGH
THE PERIOD.

TEMPS...TRENDED TOWARDS WARMER MAVMOS GUIDANCE FOR HIGHS TODAY AND
SUNDAY. ANALYSIS OF LOW LEVEL THICKNESSES SUPPORTED LEANING TOWARDS
WARMER METMOS GUIDANCE FOR MONDAY. HIGHS IN THE MID AND UPPER 50S
WILL BE COMMONPLACE OVER THE NEXT THREE DAYS. STAYED CLOSE TO MOS
GUIDANCE FOR LOWS...WITH MID AND UPPER 30S LARGELY EXPECTED TONIGHT
AND SUNDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...JAS
UPDATE...JH

000
FXUS63 KIWX 211121
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
630 AM EST SAT NOV 21 2009

.AVIATION...

PERSISTENT AND SLOWLY EXPANDING STRATOCUMULUS CLOUD DECK JUST ABOUT
INTO KFWA. CIGS RUNNING AROUND 35HFT BASED ON OBSERVATIONS WITH A
FEW SITES REPORTING MVFR VIS AS WELL. WILL HAVE THIS INTO KFWA AT
ISSUANCE TIME. QUESTION REMAINS WHETHER THIS AREA WILL DISSIPATE
WITH DIURNAL MIXING OR REMAIN INTACT AS IT DID YESTERDAY AND
OVERNIGHT. CONTINUED TO BE OPTIMISTIC WITH GRADUAL CLEARING AT KFWA
BUT DELAYED IT A FEW HOURS. KSBN SANDWICHED BETWEEN THESE CLOUDS AND
CLOUDS TO THE NORTH. ONCE MVFR BR BURNS OFF EXPECT VFR CONDITIONS
THERE WITH SCT CU DEVELOPMENT. LIGHT WINDS AND MOSTLY CLEAR SKIES BY
TONIGHT SHOULD YIELD OPTIMUM CONDITIONS FOR FOG FORMATION WITH MORE
WIDESPREAD DENSE FOG POSSIBLE. HAVE TRENDED TAFS TO MVFR BUT IFR AND
LIFR CONDITIONS WILL BE POSSIBLE AS IS OCCURRING TO OUR WEST THIS
MORNING.

&&

.SHORT TERM...

...TODAY THROUGH SUNDAY NIGHT...

HIGH PRESSURE WAS ACROSS MOST OF AREA EARLY THIS MORNING WHILE AN
UPPER LEVEL TROUGH WAS MOVING THROUGH. LITTLE SURFACE REFLECTION
FROM THE TROUGH BUT CLOUDS WERE HANGING IN ACROSS THE FAR NORTH AND
NORTHEAST AHEAD OF THIS FEATURE. MEANWHILE...AREA OF STRATOCUMULUS
CLOUDS THAT FORMED LAST NIGHT IN IL AND PERSISTED THROUGH THE DAY
HAVE DRIFTED INTO OUR SOUTHWEST COUNTIES. SATELLITE FOG PRODUCT
SHOWS THIS AREA SLOWLY EXPANDING AND DRIFTING EAST. FORECAST
CHALLENGES CONTINUE TO BE CLOUD COVER...TEMPS AND FOG POSSIBILITY IN
THE SHORT TERM PERIOD.

WITH WEAK HIGH PRESSURE AND SUBSIDENCE TODAY EXPECT A GRADUAL
DECREASE IN OVERALL CLOUDINESS THROUGH THE DAY. CLOUDS ACROSS NORTH
AND NORTHEAST SHOULD GRADUALLY DISSIPATE/EXIT OUR AREA BEHIND THE
DEPARTING TROUGH THIS AFTERNOON. A LITTLE CONCERNED WITH THE CLOUDS
IN THE SOUTHWEST THOUGH AS THEY PERSISTED YESTERDAY AND DID NOT MIX
OUT. IT IS POSSIBLE A SIMILAR SITUATION COULD OCCUR AGAIN TODAY.
WILL BE OPTIMISTIC WITH A GRADUAL ERODING OF THESE CLOUDS.
TEMPERATURES SHOULD BE VERY SIMILAR TO FRIDAY READINGS WITH SIMILAR
AIRMASS.

DRYING CONTINUES TONIGHT WITH CONTINUED SUBSIDENCE AS MID LEVEL
RIDGE NOSES INTO THE AREA. SHOULD SEE MOSTLY CLEAR SKIES AND LIGHT
WINDS EARLY WHICH SHOULD SET THE STAGE FOR FOG FORMATION LATE. SETUP
LOOKS A LITTLE BETTER THAN THIS MORNING AS RIDGE WILL BE BUILDING IN
AND DENSE FOG ALREADY FORMING TO OUR WEST NEAR THIS RIDGING THIS
MORNING.

FOG MAY TAKE SOME TIME TO BURN OFF SUNDAY MORNING BUT ONCE IT DOES
SHOULD BE ANOTHER NICE LATE NOVEMBER DAY WITH HIGHS INTO THE 50S.
CONTINUED TO BE A LITTLE CONSERVATIVE WITH POSSIBLE FOG AND STRATUS
IN THE MORNING HOURS INHIBITING TEMPERATURE RISE. FEEL FOG COULD
FORM YET AGAIN SUNDAY NIGHT AS HIGH SLIDES EAST BUT THERE MAY BE
ENOUGH GRADIENT WIND TO PRECLUDE WIDESPREAD FOG. WILL LIKELY HOLD
OFF ON ANY MENTION IN THIS PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...

MSTR WILL BE WORKING NORTH AT THE START OF THE PERIOD...BUT RH
PROFILES SUGGEST SKIES SHOULD STILL GENERALLY BE PARTLY TO MOSTLY
SUNNY WITH SOME HIGH CLOUDS. THIS WILL RESULT IN HIGHS LIKELY BEING
A FEW DEGREES WARMER THAN PREVIOUSLY THOUGHT SO HAVE BROUGHT UP A
BIT BUT HOLDING SHY OF ENSEMBLE AND MET GUIDANCE IN THE MID
50S...WHICH IS STILL ENTIRELY POSSIBLE WITH SLOWER SOLUTIONS FOR THE
SYSTEM TO THE WEST.

A BIT OF AGREEMENT ON TIMING OF THE INITIAL LOW APPROACHING THE AREA
IS ATTEMPTING TO OCCUR. AT THIS POINT...INCREASING CHANCES THAT
MONDAY NIGHT AND MAYBE EVEN THE FIRST PART OF TUESDAY MAY END UP
DRY. ENOUGH CONFIDENCE IN TRENDS TO REMOVE POPS MON EVE BUT LEAVE
UNTOUCHED LATE MON NGT THROUGH MUCH OF THE REMAINDER OF THE PERIOD.
MORE THAN LIKELY POPS WILL BE REMOVED ENTIRELY FOR REMAINDER OF
MONDAY NIGHT IN FUTURE FORECASTS. WHERE THE CHALLENGES REMAIN IS HOW
MUCH COLD AIR ARRIVES AND HOW LONG IT STICKS AROUND. 00Z OPER GFS
CONTINUES TO BRING SHOT OF -3 TO -5 C 850 MB TEMPS IN BY WEDS BUT
HAS NOW BACKED OFF ON THE MUCH COLDER SCENARIO WITH NEXT PUSH OF
COLDEST AIR...STILL ONLY AS LOW AS -6 C...PASSING BY TO THE SW. THIS
WOULD RESULT IN THE POTENTIAL FOR RAIN OR SNOW MIXED. 00Z ECMWF
PAINTS A DIFFERENT PICTURE WITH THE LOW MOVING TO THE NW SLOWER THAN
THE GFS AND THE COLDEST AIR NOT ARRIVING TILL MAINLY THURSDAY. GFS
ENSEMBLE SEEMS TO BE MIDDLE OF THE ROAD WITH PROGRESS OF SYSTEM WITH
MOST FAVORABLE TIME FRAME STILL IN THE WEDS/WEDS NGT PERIOD FOLLOWED
BY A PUSH OF COOLER AIR. WITH SO MANY QUESTIONS IN TERMS OF THERMAL
FIELDS AND TIMING...WILL LEAVE TEMPS AND PRECIP TYPES ALONE THROUGH
THE REMAINDER OF THE PERIOD WITH ANY CHANGES MADE NOW LIKELY HAVING
TO BE MODIFIED ONCE AGAIN...POTENTIAL FLIP FLOPPING. IF MODELS ARE
TO BE BELIEVED AFTER THIS SYSTEM MOVES BY...A QUICK MODERATION COULD
OCCUR WITH 00Z ECMWF SHOWING SURGE OF WELL ABOVE ZERO 850 MB TEMPS
FOR THE HOLIDAY WEEKEND AND GFS NOT TOO FAR OFF.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LASHLEY

000
FXUS63 KIND 211036
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
535 AM EST SAT NOV 21 2009

.AVIATION...DISCUSSION FOR 211200Z TAF ISSUANCE. AREAS OF IFR/LIFR
IN FOG CURRENTLY OVER THE SOUTHERN SECTIONS OF THE STATE...
OCCASIONALLY AFFECTING THE KHUF/KBMG TERMINALS. MOISTURE LAYER IS
QUITE SHALLOW...SO THESE CONDITIONS SHOULD MIX OUT FAIRLY RAPIDLY
AFTER SUNRISE...BY 211500Z.

OTHERWISE...CIGS 030-040 OVER THE NORTHERN SECTIONS OF THE LOCAL
AREA HAVE BEEN EXPANDING SLOWLY SOUTH...AFFECTING MAINLY KIND/KLAF.
210000Z UPPER AIR OBSERVATIONS INDICATE THIS MOISTURE LAYER IS QUITE
THIN AS WELL...SO EXPECTING THESE CIGS TO ERODE FROM THE EDGES AND
EVENTUALLY MIX OUT IN THE 211500Z-211700Z TIME FRAME.

SURFACE WINDS BELOW 15 KTS THROUGH 220000Z.

&&

.DISCUSSION...
QUIET MORNING IN PROGRESS AS SURFACE HIGH PRESSURE IS CENTERED OVER
EASTERN OHIO. WEAK UPPER LEVEL SHORTWAVE TRAVERSING THE REGION EARLY
THIS MORNING. AREA OF STRATOCUMULUS HAD DEVELOPED OVER NORTHERN HALF
OF THE FORECAST AREA AND WILL LIKELY SLIP INTO THE INDY METRO DURING
THE PREDAWN HOURS. WHERE SKIES WERE MAINLY CLEAR...PATCHY MIST/FOG
HAD DEVELOPED AGAIN THIS MORNING. TEMPERATURES AT 08Z WERE IN THE
30S.

FORECAST CHALLENGES TODAY FOCUS ON CLOUDS THIS MORNING...
TEMPERATURES THROUGH MONDAY...AND TRANSITION TO COLDER AND MORE
UNSETTLED PATTERN BY MIDWEEK. MODELS IN EXCELLENT AGREEMENT WITH
REGARDS TO SENSIBLE WEATHER TODAY AND SUNDAY.

AFOREMENTIONED SHORTWAVE WILL CONTINUE TO PROGRESS EAST THROUGH THE
MORNING AS HIGH REMAINS FIRMLY ENTRENCHED AT THE SURFACE. EXPECT
LOWER CLOUDS TO PERSIST THROUGH DAYBREAK ACROSS NORTHERN COUNTIES
WITH MOSTLY CLEAR SKIES ELSEWHERE. AS THE SHORTWAVE ENERGY SHIFTS
EAST INTO OHIO BY LATE MORNING HOWEVER...DO ANTICIPATE A DECREASE IN
STRATOCUMULUS COVERAGE WITH PLENTY OF SUNSHINE PROVIDING FOR YET
ANOTHER IDEAL SATURDAY IN NOVEMBER. RIDGING ALOFT WILL DEVELOP THIS
AFTERNOON AND TONIGHT ACROSS THE REGION. OTHER THAN CIRRUS SHIELD
PASSING BY TO THE SOUTHEAST IN ASSOCIATION WITH LOW PRESSURE LIFTING
OUT OF THE NORTHERN GULF COAST...SKIES WILL REMAIN GENERALLY CLEAR.

MODEL CONSENSUS CONTINUES TO TREND AWAY FROM CENTRAL INDIANA SEEING
ANY SIGNIFICANT IMPACT FROM SAID LOW PRESSURE ALONG THE GULF COAST
ON SUNDAY. HIGH PRESSURE RIDGE AT THE SURFACE EXTENDING FROM NEW
ENGLAND SOUTHWEST BACK INTO THE OHIO VALLEY WILL KEEP THIS LOW FROM
TAKING A MORE NORTHERLY TRACK INTO THE TENNESSEE VALLEY...AND
CONSEQUENTLY PROVIDE A VERY PLEASANT SUNDAY FOR THE THIRD STRAIGHT
WEEK. THE ONLY IMPACTS SHOULD BE A SUBTLE INCREASE IN MID AND HIGH
LEVEL CLOUDS INTO THE REGION FROM THE SOUTHEAST SUNDAY AFTERNOON AND
NIGHT. MORE SIGNIFICANT 285-300K ISENTROPIC LIFT ON BOTH NAM/OP GFS
NOW REMAIN WELL DISPLACED TO THE SOUTHEAST OF THE FORECAST AREA.
CONSIDERING A PREDOMINANT EASTERLY FLOW IN THE LOWER LEVELS KEEPING
BOUNDARY LAYER FAIRLY DRY...FEEL CONFIDENT IN REMOVING 20 POPS FROM
SUNDAY NIGHT FORECAST. SKIES MAY ACTUALLY END UP BEING MOSTLY CLEAR
NORTHWEST OF THE INDY METRO.

WEAKENING UPPER LOW ASSOCIATED WITH THE GULF COAST LOW WILL BECOME
ABSORBED BY SIGNIFICANT UPPER TROUGH AS IT BECOMES WELL ESTABLISHED
OVER THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THE AMPLIFICATION OF
THE TROUGH WILL SPARK DEVELOPMENT OF LOW PRESSURE AND A COLD FRONT
MONDAY NIGHT. SPECIFIC MODELS DIFFER ON HOW FAST THE LOW PRESSURE
WAVE SPINS UP AND ITS LOCATION BY TUESDAY MORNING. FAVOR MORE
CONSERVATIVE AND SLOWER 00Z NAM/ECMWF SOLUTION...WITH THE LOW
PRESSURE NEAR KANSAS CITY BY TUESDAY MORNING. 00Z OP GFS/GEM/GFS
ENSEMBLE MEAN BREAK DOWN HIGH PRESSURE OFF THE CANADIAN MARITIMES
FASTER AND CONSEQUENTLY PROGRESS THE LOW AND FRONT FURTHER EAST.
WARM FRONT LIFTS NORTH ACROSS THE FORECAST AREA BY MONDAY NIGHT WITH
SOUTHERLY FLOW DEVELOPING OUT AHEAD OF THE APPROACHING COLD FRONT.
LIKELY TO SEE AN INCREASE IN MID LEVEL CLOUDS AS DEEPER MOISTURE IN
ADVECTS INTO CENTRAL INDIANA MONDAY AFTERNOON AND NIGHT IN THE
VICINITY OF THE WARM FRONT.

ADJUSTED RAIN CHANCES FOR TUESDAY AS COLD FRONT LIKELY TO NOT ARRIVE
UNTIL LATE TUESDAY...POSSIBLY EVEN TUESDAY NIGHT SHOULD THE 00Z
ECMWF SOLUTION BE REALIZED. WITH UNCERTAINTY OF THE TIMING OF THE
FRONTAL PASSAGE...WILL CONTINUE WITH JUST A MENTION OF RAIN IN THE
FORECAST TUESDAY NIGHT. OP GFS/ECMWF BOTH DROPPING LOW LEVEL
THICKNESSES TOWARDS CRITICAL VALUES NEEDED FOR A FEW WET SNOWFLAKES
TO MIX IN BY EARLY WEDNESDAY. THE PASSAGE OF THE COLD FRONT WILL
SIGNAL A CHANGE TO A MORE UNSETTLED AND COLDER REGIME FOR THE REGION
FOR THE SECOND HALF OF THE UPCOMING WEEK. WITH UPPER LEVEL LOW
PROGRESSING SLOWLY ACROSS THE LOWER GREAT LAKES WEDNESDAY AND
THURSDAY...LOWER LEVELS DO APPEAR TO BECOME SUFFICIENTLY COLD ENOUGH
FOR A FEW SNOW SHOWERS...ESPECIALLY WEDNESDAY NIGHT AND THANKSGIVING
DAY. WILL CONTINUE WITH LOW CHANCES FOR RAIN/SNOW SHOWERS THROUGH
THE PERIOD.

TEMPS...TRENDED TOWARDS WARMER MAVMOS GUIDANCE FOR HIGHS TODAY AND
SUNDAY. ANALYSIS OF LOW LEVEL THICKNESSES SUPPORTED LEANING TOWARDS
WARMER METMOS GUIDANCE FOR MONDAY. HIGHS IN THE MID AND UPPER 50S
WILL BE COMMONPLACE OVER THE NEXT THREE DAYS. STAYED CLOSE TO MOS
GUIDANCE FOR LOWS...WITH MID AND UPPER 30S LARGELY EXPECTED TONIGHT
AND SUNDAY NIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...JAS

000
FXUS63 KIWX 210907
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
407 AM EST SAT NOV 21 2009

.SHORT TERM...

...TODAY THROUGH SUNDAY NIGHT...

HIGH PRESSURE WAS ACROSS MOST OF AREA EARLY THIS MORNING WHILE AN
UPPER LEVEL TROUGH WAS MOVING THROUGH. LITTLE SURFACE REFLECTION
FROM THE TROUGH BUT CLOUDS WERE HANGING IN ACROSS THE FAR NORTH AND
NORTHEAST AHEAD OF THIS FEATURE. MEANWHILE...AREA OF STRATOCUMULUS
CLOUDS THAT FORMED LAST NIGHT IN IL AND PERSISTED THROUGH THE DAY
HAVE DRIFTED INTO OUR SOUTHWEST COUNTIES. SATELLITE FOG PRODUCT
SHOWS THIS AREA SLOWLY EXPANDING AND DRIFTING EAST. FORECAST
CHALLENGES CONTINUE TO BE CLOUD COVER...TEMPS AND FOG POSSIBILITY IN
THE SHORT TERM PERIOD.

WITH WEAK HIGH PRESSURE AND SUBSIDENCE TODAY EXPECT A GRADUAL
DECREASE IN OVERALL CLOUDINESS THROUGH THE DAY. CLOUDS ACROSS NORTH
AND NORTHEAST SHOULD GRADUALLY DISSIPATE/EXIT OUR AREA BEHIND THE
DEPARTING TROUGH THIS AFTERNOON. A LITTLE CONCERNED WITH THE CLOUDS
IN THE SOUTHWEST THOUGH AS THEY PERSISTED YESTERDAY AND DID NOT MIX
OUT. IT IS POSSIBLE A SIMILAR SITUATION COULD OCCUR AGAIN TODAY.
WILL BE OPTIMISTIC WITH A GRADUAL ERODING OF THESE CLOUDS.
TEMPERATURES SHOULD BE VERY SIMILAR TO FRIDAY READINGS WITH SIMILAR
AIRMASS.

DRYING CONTINUES TONIGHT WITH CONTINUED SUBSIDENCE AS MID LEVEL
RIDGE NOSES INTO THE AREA. SHOULD SEE MOSTLY CLEAR SKIES AND LIGHT
WINDS EARLY WHICH SHOULD SET THE STAGE FOR FOG FORMATION LATE. SETUP
LOOKS A LITTLE BETTER THAN THIS MORNING AS RIDGE WILL BE BUILDING IN
AND DENSE FOG ALREADY FORMING TO OUR WEST NEAR THIS RIDGING THIS
MORNING.

FOG MAY TAKE SOME TIME TO BURN OFF SUNDAY MORNING BUT ONCE IT DOES
SHOULD BE ANOTHER NICE LATE NOVEMBER DAY WITH HIGHS INTO THE 50S.
CONTINUED TO BE A LITTLE CONSERVATIVE WITH POSSIBLE FOG AND STRATUS
IN THE MORNING HOURS INHIBITING TEMPERATURE RISE. FEEL FOG COULD
FORM YET AGAIN SUNDAY NIGHT AS HIGH SLIDES EAST BUT THERE MAY BE
ENOUGH GRADIENT WIND TO PRECLUDE WIDESPREAD FOG. WILL LIKELY HOLD
OFF ON ANY MENTION IN THIS PERIOD.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...

MSTR WILL BE WORKING NORTH AT THE START OF THE PERIOD...BUT RH
PROFILES SUGGEST SKIES SHOULD STILL GENERALLY BE PARTLY TO MOSTLY
SUNNY WITH SOME HIGH CLOUDS. THIS WILL RESULT IN HIGHS LIKELY BEING
A FEW DEGREES WARMER THAN PREVIOUSLY THOUGHT SO HAVE BROUGHT UP A
BIT BUT HOLDING SHY OF ENSEMBLE AND MET GUIDANCE IN THE MID
50S...WHICH IS STILL ENTIRELY POSSIBLE WITH SLOWER SOLUTIONS FOR THE
SYSTEM TO THE WEST.

A BIT OF AGREEMENT ON TIMING OF THE INITIAL LOW APPROACHING THE AREA
IS ATTEMPTING TO OCCUR. AT THIS POINT...INCREASING CHANCES THAT
MONDAY NIGHT AND MAYBE EVEN THE FIRST PART OF TUESDAY MAY END UP
DRY. ENOUGH CONFIDENCE IN TRENDS TO REMOVE POPS MON EVE BUT LEAVE
UNTOUCHED LATE MON NGT THROUGH MUCH OF THE REMAINDER OF THE PERIOD.
MORE THAN LIKELY POPS WILL BE REMOVED ENTIRELY FOR REMAINDER OF
MONDAY NIGHT IN FUTURE FORECASTS. WHERE THE CHALLENGES REMAIN IS HOW
MUCH COLD AIR ARRIVES AND HOW LONG IT STICKS AROUND. 00Z OPER GFS
CONTINUES TO BRING SHOT OF -3 TO -5 C 850 MB TEMPS IN BY WEDS BUT
HAS NOW BACKED OFF ON THE MUCH COLDER SCENARIO WITH NEXT PUSH OF
COLDEST AIR...STILL ONLY AS LOW AS -6 C...PASSING BY TO THE SW. THIS
WOULD RESULT IN THE POTENTIAL FOR RAIN OR SNOW MIXED. 00Z ECMWF
PAINTS A DIFFERENT PICTURE WITH THE LOW MOVING TO THE NW SLOWER THAN
THE GFS AND THE COLDEST AIR NOT ARRIVING TILL MAINLY THURSDAY. GFS
ENSEMBLE SEEMS TO BE MIDDLE OF THE ROAD WITH PROGRESS OF SYSTEM WITH
MOST FAVORABLE TIME FRAME STILL IN THE WEDS/WEDS NGT PERIOD FOLLOWED
BY A PUSH OF COOLER AIR. WITH SO MANY QUESTIONS IN TERMS OF THERMAL
FIELDS AND TIMING...WILL LEAVE TEMPS AND PRECIP TYPES ALONE THROUGH
THE REMAINDER OF THE PERIOD WITH ANY CHANGES MADE NOW LIKELY HAVING
TO BE MODIFIED ONCE AGAIN...POTENTIAL FLIP FLOPPING. IF MODELS ARE
TO BE BELIEVED AFTER THIS SYSTEM MOVES BY...A QUICK MODERATION COULD
OCCUR WITH 00Z ECMWF SHOWING SURGE OF WELL ABOVE ZERO 850 MB TEMPS
FOR THE HOLIDAY WEEKEND AND GFS NOT TOO FAR OFF.

&&

.AVIATION...

CONTINUED CHALLENGES WITH FOG FORECASTS OVERNIGHT AS PATCH OF 3-4KFT
CLOUDS ARE DRIFTING ACROSS THE AREA. UPPER SHORT WAVE NEARING KSBN
AT ISSUANCE TIME AND WILL TRAVERSE THE AREA OVERNIGHT. LIFT AHEAD OF
THIS FEATURE ENOUGH TO GENERATE SMALL AREA OF CLOUDS IN ADDITION TO
CLOUDS FROM TODAY ACROSS IL THAT HAVE DRIFTED EAST AND REFUSE TO
DISSIPATE. THESE VFR CIGS ABOUT TO MOVE INTO KSBN AND WILL SLOWLY
WORK TOWARD KFWA NEXT SEVERAL HOURS. WITH THESE CLOUDS DO NOT
EXPECTED IFR VIS DUE TO FOG BUT MVFR STILL POSSIBLE AND STAYED THE
COURSE WITH THOSE FOR NOW. IF CLOUDS BEGIN TO DISSIPATE IN WAKE OF
SHORT WAVE PASSAGE...COULD SEE VIS DROP LATE. WILL MONITOR FOR THESE
TRENDS. OTHERWISE EXPECT WEAK MIXING TO LEAVE BEHIND SCT CLOUDS ON
SATURDAY WITH LIGHT WINDS.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LASHLEY
LONG TERM...FISHER
AVIATION...LASHLEY

000
FXUS63 KIND 210834
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
334 AM EST SAT NOV 21 2009

.DISCUSSION...
QUIET MORNING IN PROGRESS AS SURFACE HIGH PRESSURE IS CENTERED OVER
EASTERN OHIO. WEAK UPPER LEVEL SHORTWAVE TRAVERSING THE REGION EARLY
THIS MORNING. AREA OF STRATOCUMULUS HAD DEVELOPED OVER NORTHERN HALF
OF THE FORECAST AREA AND WILL LIKELY SLIP INTO THE INDY METRO DURING
THE PREDAWN HOURS. WHERE SKIES WERE MAINLY CLEAR...PATCHY MIST/FOG
HAD DEVELOPED AGAIN THIS MORNING. TEMPERATURES AT 08Z WERE IN THE
30S.

FORECAST CHALLENGES TODAY FOCUS ON CLOUDS THIS MORNING...
TEMPERATURES THROUGH MONDAY...AND TRANSITION TO COLDER AND MORE
UNSETTLED PATTERN BY MIDWEEK. MODELS IN EXCELLENT AGREEMENT WITH
REGARDS TO SENSIBLE WEATHER TODAY AND SUNDAY.

AFOREMENTIONED SHORTWAVE WILL CONTINUE TO PROGRESS EAST THROUGH THE
MORNING AS HIGH REMAINS FIRMLY ENTRENCHED AT THE SURFACE. EXPECT
LOWER CLOUDS TO PERSIST THROUGH DAYBREAK ACROSS NORTHERN COUNTIES
WITH MOSTLY CLEAR SKIES ELSEWHERE. AS THE SHORTWAVE ENERGY SHIFTS
EAST INTO OHIO BY LATE MORNING HOWEVER...DO ANTICIPATE A DECREASE IN
STRATOCUMULUS COVERAGE WITH PLENTY OF SUNSHINE PROVIDING FOR YET
ANOTHER IDEAL SATURDAY IN NOVEMBER. RIDGING ALOFT WILL DEVELOP THIS
AFTERNOON AND TONIGHT ACROSS THE REGION. OTHER THAN CIRRUS SHIELD
PASSING BY TO THE SOUTHEAST IN ASSOCIATION WITH LOW PRESSURE LIFTING
OUT OF THE NORTHERN GULF COAST...SKIES WILL REMAIN GENERALLY CLEAR.

MODEL CONSENSUS CONTINUES TO TREND AWAY FROM CENTRAL INDIANA SEEING
ANY SIGNIFICANT IMPACT FROM SAID LOW PRESSURE ALONG THE GULF COAST
ON SUNDAY. HIGH PRESSURE RIDGE AT THE SURFACE EXTENDING FROM NEW
ENGLAND SOUTHWEST BACK INTO THE OHIO VALLEY WILL KEEP THIS LOW FROM
TAKING A MORE NORTHERLY TRACK INTO THE TENNESSEE VALLEY...AND
CONSEQUENTLY PROVIDE A VERY PLEASANT SUNDAY FOR THE THIRD STRAIGHT
WEEK. THE ONLY IMPACTS SHOULD BE A SUBTLE INCREASE IN MID AND HIGH
LEVEL CLOUDS INTO THE REGION FROM THE SOUTHEAST SUNDAY AFTERNOON AND
NIGHT. MORE SIGNIFICANT 285-300K ISENTROPIC LIFT ON BOTH NAM/OP GFS
NOW REMAIN WELL DISPLACED TO THE SOUTHEAST OF THE FORECAST AREA.
CONSIDERING A PREDOMINANT EASTERLY FLOW IN THE LOWER LEVELS KEEPING
BOUNDARY LAYER FAIRLY DRY...FEEL CONFIDENT IN REMOVING 20 POPS FROM
SUNDAY NIGHT FORECAST. SKIES MAY ACTUALLY END UP BEING MOSTLY CLEAR
NORTHWEST OF THE INDY METRO.

WEAKENING UPPER LOW ASSOCIATED WITH THE GULF COAST LOW WILL BECOME
ABSORBED BY SIGNIFICANT UPPER TROUGH AS IT BECOMES WELL ESTABLISHED
OVER THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THE AMPLIFICATION OF
THE TROUGH WILL SPARK DEVELOPMENT OF LOW PRESSURE AND A COLD FRONT
MONDAY NIGHT. SPECIFIC MODELS DIFFER ON HOW FAST THE LOW PRESSURE
WAVE SPINS UP AND ITS LOCATION BY TUESDAY MORNING. FAVOR MORE
CONSERVATIVE AND SLOWER 00Z NAM/ECMWF SOLUTION...WITH THE LOW
PRESSURE NEAR KANSAS CITY BY TUESDAY MORNING. 00Z OP GFS/GEM/GFS
ENSEMBLE MEAN BREAK DOWN HIGH PRESSURE OFF THE CANADIAN MARITIMES
FASTER AND CONSEQUENTLY PROGRESS THE LOW AND FRONT FURTHER EAST.
WARM FRONT LIFTS NORTH ACROSS THE FORECAST AREA BY MONDAY NIGHT WITH
SOUTHERLY FLOW DEVELOPING OUT AHEAD OF THE APPROACHING COLD FRONT.
LIKELY TO SEE AN INCREASE IN MID LEVEL CLOUDS AS DEEPER MOISTURE IN
ADVECTS INTO CENTRAL INDIANA MONDAY AFTERNOON AND NIGHT IN THE
VICINITY OF THE WARM FRONT.

ADJUSTED RAIN CHANCES FOR TUESDAY AS COLD FRONT LIKELY TO NOT ARRIVE
UNTIL LATE TUESDAY...POSSIBLY EVEN TUESDAY NIGHT SHOULD THE 00Z
ECMWF SOLUTION BE REALIZED. WITH UNCERTAINTY OF THE TIMING OF THE
FRONTAL PASSAGE...WILL CONTINUE WITH JUST A MENTION OF RAIN IN THE
FORECAST TUESDAY NIGHT. OP GFS/ECMWF BOTH DROPPING LOW LEVEL
THICKNESSES TOWARDS CRITICAL VALUES NEEDED FOR A FEW WET SNOWFLAKES
TO MIX IN BY EARLY WEDNESDAY. THE PASSAGE OF THE COLD FRONT WILL
SIGNAL A CHANGE TO A MORE UNSETTLED AND COLDER REGIME FOR THE REGION
FOR THE SECOND HALF OF THE UPCOMING WEEK. WITH UPPER LEVEL LOW
PROGRESSING SLOWLY ACROSS THE LOWER GREAT LAKES WEDNESDAY AND
THURSDAY...LOWER LEVELS DO APPEAR TO BECOME SUFFICIENTLY COLD ENOUGH
FOR A FEW SNOW SHOWERS...ESPECIALLY WEDNESDAY NIGHT AND THANKSGIVING
DAY. WILL CONTINUE WITH LOW CHANCES FOR RAIN/SNOW SHOWERS THROUGH
THE PERIOD.

TEMPS...TRENDED TOWARDS WARMER MAVMOS GUIDANCE FOR HIGHS TODAY AND
SUNDAY. ANALYSIS OF LOW LEVEL THICKNESSES SUPPORTED LEANING TOWARDS
WARMER METMOS GUIDANCE FOR MONDAY. HIGHS IN THE MID AND UPPER 50S
WILL BE COMMONPLACE OVER THE NEXT THREE DAYS. STAYED CLOSE TO MOS
GUIDANCE FOR LOWS...WITH MID AND UPPER 30S LARGELY EXPECTED TONIGHT
AND SUNDAY NIGHT.

&&

.AVIATION DISCUSSION...FOR THE 06Z TAFS
HIGH PRESSURE WILL REMAINED CENTERED OVER INDIANA THROUGH THE TAF
PERIOD. CLEAR SKIES...CALM WINDS AND SOME LOW LEVEL MOISTURE WILL
CAUSE VISIBILITIES TO DECREASE TO IFR LEVELS IN FOG BY 11Z. DUE TO
DRYING THAT OCCURRED ON FRIDAY THE FOG SHOULD NOT BE AS WIDESPREAD
AND DENSE AS FRIDAY MORNING. VISIBILITIES WILL QUICKLY INCREASE TO
VFR BY 15Z.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...RYAN
AVIATION...SH

000
FXUS63 KIWX 210536
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1235 AM EST SAT NOV 21 2009

.AVIATION...

CONTINUED CHALLENGES WITH FOG FORECASTS OVERNIGHT AS PATCH OF 3-4KFT
CLOUDS ARE DRIFTING ACROSS THE AREA. UPPER SHORT WAVE NEARING KSBN
AT ISSUANCE TIME AND WILL TRAVERSE THE AREA OVERNIGHT. LIFT AHEAD OF
THIS FEATURE ENOUGH TO GENERATE SMALL AREA OF CLOUDS IN ADDITION TO
CLOUDS FROM TODAY ACROSS IL THAT HAVE DRIFTED EAST AND REFUSE TO
DISSIPATE. THESE VFR CIGS ABOUT TO MOVE INTO KSBN AND WILL SLOWLY
WORK TOWARD KFWA NEXT SEVERAL HOURS. WITH THESE CLOUDS DO NOT
EXPECTED IFR VIS DUE TO FOG BUT MVFR STILL POSSIBLE AND STAYED THE
COURSE WITH THOSE FOR NOW. IF CLOUDS BEGIN TO DISSIPATE IN WAKE OF
SHORT WAVE PASSAGE...COULD SEE VIS DROP LATE. WILL MONITOR FOR THESE
TRENDS. OTHERWISE EXPECT WEAK MIXING TO LEAVE BEHIND SCT CLOUDS ON
SATURDAY WITH LIGHT WINDS.

&&

.SHORT TERM.../TONIGHT THROUGH SATURDAY NIGHT/...
MUCH MORE OPTIMISTIC SHORT TERM PERIOD WITH HIGH TEMPS RETURNING
TO ABOVE NORMAL FOR SATURDAY. UPPER LOW THAT SPOILED THE WORK WEEK
IS CENTERED OVER SOUTHERN ONTARIO WHILE A FOLLOWUP SHTWV IS MOVING
INTO ILLINOIS. THIS FEATURE IS NOT GENERATING AS MUCH CLOUD COVER
AS ANTICIPATED EXCEPT OVER THE NE THIRD OF THE CWA WHERE IT HAS
MOVED INTO AN AREA OF MOISTURE LEFT BEHIND BY RETREATING UPPER
LOW. MODELS INDICATE THIS AREA OF ENHANCED RH THROUGH THE MID
LEVELS TO REMAIN OVERNIGHT AND INTO SATURDAY. WHILE THIS WILL
CURTAILS AN OTHERWISE IDEAL RAD COOLING SETUP COOLING/MOISTURE
STILL SUFFICIENT FOR OVERNIGHT FOG TO DEVELOP. SOUTH OF THICKER
CLOUD POTENTIAL WHERE SKIES SHOULD BE CLEARER WENT SLIGHTLY COOLER
WITH LOWS BUT THIS ALSO SETS UP MORE SIGNIFICANT FOG DEVELOPMENT.

SATURDAY WILL SEE ABV NORMAL TEMPS AS MIXING TO MODEL AVERAGED H92
TEMPS YIELDS HIGHS IN THE MID 50S.  GRIDS ARE SLIGHTLY COOLER THAN
THIS IN THE NORTHEAST WHERE MORE CLOUDS ARE EXPECTED AND WARMER IN
SOUTHERN AREAS WHERE TEMPS TODAY ARE REACHING 52-54 DESPITE COOLER
TEMPS ALOFT.

&&

.LONG TERM.../SUNDAY THROUGH FRIDAY/...

GENERAL SOUTHWEST FLOW REGIME OF LATE WILL BEGIN TO BREAK DOWN
DURING IN THE PERIOD. STRONG LL TEMPERATURE GRADIENT OVER THE
NORTHERN PAC WILL SET THE STAGE FOR A SUBTLE PATTERN CHANGE AS A
WEAK SFC WAVE NEAR THE EASTERN ALEUTIANS INTERACTS WITH A
STRENGTHENING UPPER LEVEL IMPULSE PUSHING OVER THE WESTERN
ALEUTIANS. ORIENTATION OF THE STRENGTHENING UPPER LEVEL JET WILL
SUPPORT DEEPENING OF THE AFOREMENTIONED UPPER LEVEL TROUGH WITH
INCREASING NW LL FLOW SUPPORTING AMPLE CAA...WITH TROUGHING EXPECTED
INTO THE WESTERN US BY EARLY NEXT WEEK. GIVEN THE POSITION OF THE
EXPECTED UPPER LEVEL JET OVER THE WESTERN CONUS WITH WIDESPREAD
DOWNSTREAM RIDGING ALREADY IN PROGRESS...EXPECT A PERIOD OF UPPER
LEVEL TROUGH DIGGING AS DEPICTED IN GEM AND ECMWF PROGS. DEGREE OF
DIGGING AND AFFECT ON THE PROGRESSIVE NATURE OF THE FLOW IS STILL
YET TO BE DETERMINED. IN ADDITION...CLOSING OF THE UPPER LEVEL WAVE
AS SUPPORTED IN NEARLY ALL DETERMINISTIC RUNS LENDS CREDENCE TO A
SEMI SPLIT FLOW PATTERN WITH THE BULK OF CAA RESIDING WELL NORTH OF
THE REGION. A SHIFT TO AT OR BELOW NORMAL TEMPERATES IS WARRANTED IN
DAYS 5-7. HOWEVER...THE VERY COLD PROGS IN THE GFS MAY BE TOO
AGGRESSIVE GIVEN CONCERNS ON SYSTEM EVOLUTION. BOTTOM LINE...HAVE
HELD CLOSER TO ECMWF NUMBERS...WITH A HEAVY TREND TO CLIMO. THIS
WILL CERTAINLY SUPPORT A CHANCE OF MIXED PRECIP LATE IN THE PERIOD.
HOWEVER...AT THIS POINT ACCUMULATING SNOWFALL LOOKS TO REMAIN NORTH
OF THE REGION AT THIS POINT AS THE FLOW WILL REMAIN SOMEWHAT
PROGRESSIVE.

SUNDAY THROUGH MONDAY...GOMEX DISTURBANCE WILL EJECT TOWARD THE
EASTERN OH VALLEY WITH AN INCREASE IN HIGH AND MID LEVEL CLOUDS
EXPECTED. WARM PROFILES WILL SUPPORT TEMPS IN THE 50S...WITH THE
AMOUNT OF INSOLATION DICTATING THE DEGREE OF T RISE HEAVILY. A FEW
SOLUTIONS SUGGEST THE FAR EASTERN FA COULD GET CLIPPED BY A PERIOD
OF LIGHT RAIN LATE IN THE DAY. HOWEVER...CONCERNS ON DRY PROFILES
AND TRACK VARIABILITY DOES NOT WARRANT POP ADDITION. EXPECT ANOTHER
MILD DAY ON MON...WITH INCREASING MID AND HIGH CLOUDS LIKELY
LIMITING SHARPER T RISES IN DISTURBED SW FLOW.

TUE-FRI...PREFER A TREND TO AN ECMWF SOLUTION GIVEN PREFERRED
HANDLING OF UPPER LEVEL MOMENTUM FIELDS. SLOWER ARRIVAL OF THIS
SYSTEM IS PREFERRED GIVEN NORTHERN STREAM WAVE SPLIT AND GIVEN
LIKELY CLOSING OF THE UPPER LEVEL CIRCULATION. MAIN CHANGES TO THE
GRIDS TO REFLECT THIS SOLUTION WERE TO WARM TEMPS TUE AND SLIGHTLY
WED...AND SHIFT SNOW MENTION TO THE THE LATER PERIODS. WITH
CONTINUOUS SIGNALS SUPPORTING PROLONG NEGATIVE MSLP AND HEIGHT
ANOMALIES OVER THE GREAT LAKES THROUGH THE PERIOD...FEEL IT WAS
PRUDENT TO RAISE POPS TO 40 IN MANY PERIODS GIVEN CLIMO NUMBERS
ACROSS THE FA NOW AT OR ABOVE 30 PER 12 HOUR.

&&



.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUDINGTON
LONG TERM...JC
AVIATION...LASHLEY

000
FXUS63 KIND 210435
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1130 PM EST FRI NOV 20 2009

.AVIATION DISCUSSION...FOR THE 06Z TAFS
HIGH PRESSURE WILL REMAINED CENTERED OVER INDIANA THROUGH THE TAF
PERIOD. CLEAR SKIES...CALM WINDS AND SOME LOW LEVEL MOISTURE WILL
CAUSE VISIBILITIES TO DECREASE TO IFR LEVELS IN FOG BY 11Z. DUE TO
DRYING THAT OCCURED ON FRIDAY THE FOG SHOULD NOT BE AS WIDESPREAD
AND DENSE AS FRIDAY MORNING. VISIBILITIES WILL QUICKLY INCREASE TO
VFR BY 15Z.

&&

.UPDATE...
MINOR ADJUSTMENTS MADE TO TONIGHT/S LOWS. DROPPED LAF/IND/MIE A
DEGREE OR TWO. SKIES ARE CLEAR...AND MANY STATIONS ALREADY
REPORTING UPPER 30S.  OTHERWISE...FORECAST ON TRACK.


&&

.PREV DISCUSSION... /ISSUED 800 PM EST FRI NOV 20 2009/

AVIATION...DISCUSSION FOR 210000Z TAF ISSUANCE.
HIGH PRESSURE WILL CONTROL INDIANAS WEATHER THROUGH THE TAF PERIOD.
WITH THIS STABLE SYSTEM TAFS WILL START OUT VFR. THE CLEAR
SKIES...LIGHT TO CALM WINDS AND SOME LOW LEVEL MOISTURE REMAINING
WILL CAUSE FOG TO DEVELOP AFTER 05Z-08Z DECREASING VISIBILITIES TO
MVFR. THEY WILL CONTINUE TO DECREASE TO IFR AFTER 10Z. AREAS OF LIFR
IN FOG IS POSSIBLE. THE SUNNY SKIES ON FRIDAY HAVE ALLOWED SURFACE
LEVELS TO DRY OUT SOME SO THE FOG WILL NOT BE AS WIDESPREAD AS
FRIDAY MORNING. THE CLEAR SKIES WILL CAUSE THE FOG TO QUICKLY BURN
OFF AFTER SUNRISE. BY 15Z VFR CONDITIONS CAN BE EXPECTED.

DISCUSSION...
UPPER LOW HAS MOVED WELL TO OUR EAST AND WEAK HIGH PRESSURE OVER THE
MID MISSISSIPPI VALLEY WILL DOMINATE OUR WEATHER THROUGH EARLY
SUNDAY AND POSSIBLY LONGER DEPENDING ON FAR NORTH A DEVELOPING LOW
PRESSURE SYSTEM OVER TEXAS MOVES LATE SUNDAY OR MONDAY.

THE MAIN WEATHER CHALLENGES INCLUDE CHANCE OF FOG LATE
TONIGHT...RAIN CHANCES SUNDAY NIGHT THROUGH MIDWEEK AND
PRECIPITATION TYPE IF IT OCCURS FOR THANKSGIVING DAY.

THE GROUND HAS HAD A HALF A DAY TO DRY OUT AND FOG SHOULD NOT BE
NEARLY AS EXTENSIVE AS LAST NIGHT.  BUT CURRENT CROSS OVER
TEMPERATURES ARE NEAR FORETASTED LOW AND WITH LIGHT WINDS AND MOSTLY
CLEAR SKIES WILL ADD MENTION OF PATCHY FOG. NAM SOUNDING INDICATES
SC IS POSSIBLE LATER TONIGHT AND THERE IS A SC DECK CURRENTLY OVER
NORTH CENTRAL ILLINOIS.

QUIET AND UNEVENTFUL WEATHER WILL BE THE RULE SATURDAY AND SATURDAY
NIGHT AS WEAK HIGH PRESSURE MOVES EASTWARD ACROSS OUR REGION.

THE MODELS ARE VERY WISHY WASHY ON WHETHER MOISTURE FROM THE LOW IN
OUR SOUTH WILL TRACK THIS FAR NORTH.  THEY ARE ALL A LITTLE SLOWER
SO WILL NOT MENTION ANY PRECIP FOR SUNDAY AFTERNOON.  THE GFS IS
DRY...THE NAM AND GEM REGIONAL BRING IT INTO OUR AREA AND THEY ALSO
LINGER SOME PRECIP INTO MONDAY.  THE EUROPEAN MODEL HINTS SOME
PRECIP MAY MOVE THIS FAR NORTH...BUT LITTLE MORE THAN A TRACE.  FOR
NOW WILL CONTINUE A 20 PERCENT POPS ALONG AND SOUTHEAST OF A
WASHINGTON TO INDY LINE SUNDAY NIGHT.

IN THE EXTENDED MODELS HAVE TRENDED A LITTLE SLOWER WITH NEXT COLD
FRONT WITH IT NOW MOVING IN LATE TUESDAY OR EARLY WEDNESDAY. WILL
DELAY ONSET OF PRECIP A LITTLE WITH THIS FORECAST.

MODELS BRING A STRONG UPPER TROUGH ACROSS OUR REGION THANKSGIVING
DAY. BUT THERE IS SOME DISAGREEMENT ON HOW MUCH COLD AIR GETS
TRAPPED INTO THIS SYSTEM.  THE GFS HAS 1000-850 MB THICKNESS OF 1285
METERS WHICH WOULD BE MOSTLY SNOW.  THE EUROPEAN HAD 1000-850 MB
THICKNESS IN THE LIQUID CATEGORY.  THE GEM NW MODEL HINTED LOW LEVEL
THICKNESS MAY DROP BELOW CRITICAL THICKNESS BY THANKSGIVING. FOR NOW
WILL MENTION LOW CHANCES OF MIXED PRECIP FROM INDY N AND EAST
THANKSGIVING AND SLIGHT CHANCES OF RAIN SHOWERS ELSEWHERE.  ALSO
WENT A LITTLE COLDER THAN HPC TEMPERATURES THIS PERIOD.

AN AREA OF HIGH PRESSURE WILL MOVE EAST ACROSS THE TENNESSEE AND
OHIO VALLEYS FRIDAY AND DRY AND FAIR WEATHER WILL BE THE RULE THEN.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH
UPDATE...TDUD

000
FXUS63 KIND 210249
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
949 PM EST FRI NOV 20 2009

.UPDATE...
MINOR ADJUSTMENTS MADE TO TONIGHT/S LOWS. DROPPED LAF/IND/MIE A
DEGREE OR TWO. SKIES ARE CLEAR...AND MANY STATIONS ALREADY
REPORTING UPPER 30S.  OTHERWISE...FORECAST ON TRACK.


&&

.PREV DISCUSSION... /ISSUED 800 PM EST FRI NOV 20 2009/

AVIATION...DISCUSSION FOR 210000Z TAF ISSUANCE.
HIGH PRESSURE WILL CONTROL INDIANAS WEATHER THROUGH THE TAF PERIOD.
WITH THIS STABLE SYSTEM TAFS WILL START OUT VFR. THE CLEAR
SKIES...LIGHT TO CALM WINDS AND SOME LOW LEVEL MOISTURE REMAINING
WILL CAUSE FOG TO DEVELOP AFTER 05Z-08Z DECREASING VISIBILITIES TO
MVFR. THEY WILL CONTINUE TO DECREASE TO IFR AFTER 10Z. AREAS OF LIFR
IN FOG IS POSSIBLE. THE SUNNY SKIES ON FRIDAY HAVE ALLOWED SURFACE
LEVELS TO DRY OUT SOME SO THE FOG WILL NOT BE AS WIDESPREAD AS
FRIDAY MORNING. THE CLEAR SKIES WILL CAUSE THE FOG TO QUICKLY BURN
OFF AFTER SUNRISE. BY 15Z VFR CONDITIONS CAN BE EXPECTED.

DISCUSSION...
UPPER LOW HAS MOVED WELL TO OUR EAST AND WEAK HIGH PRESSURE OVER THE
MID MISSISSIPPI VALLEY WILL DOMINATE OUR WEATHER THROUGH EARLY
SUNDAY AND POSSIBLY LONGER DEPENDING ON FAR NORTH A DEVELOPING LOW
PRESSURE SYSTEM OVER TEXAS MOVES LATE SUNDAY OR MONDAY.

THE MAIN WEATHER CHALLENGES INCLUDE CHANCE OF FOG LATE
TONIGHT...RAIN CHANCES SUNDAY NIGHT THROUGH MIDWEEK AND
PRECIPITATION TYPE IF IT OCCURS FOR THANKSGIVING DAY.

THE GROUND HAS HAD A HALF A DAY TO DRY OUT AND FOG SHOULD NOT BE
NEARLY AS EXTENSIVE AS LAST NIGHT.  BUT CURRENT CROSS OVER
TEMPERATURES ARE NEAR FORETASTED LOW AND WITH LIGHT WINDS AND MOSTLY
CLEAR SKIES WILL ADD MENTION OF PATCHY FOG. NAM SOUNDING INDICATES
SC IS POSSIBLE LATER TONIGHT AND THERE IS A SC DECK CURRENTLY OVER
NORTH CENTRAL ILLINOIS.

QUIET AND UNEVENTFUL WEATHER WILL BE THE RULE SATURDAY AND SATURDAY
NIGHT AS WEAK HIGH PRESSURE MOVES EASTWARD ACROSS OUR REGION.

THE MODELS ARE VERY WISHY WASHY ON WHETHER MOISTURE FROM THE LOW IN
OUR SOUTH WILL TRACK THIS FAR NORTH.  THEY ARE ALL A LITTLE SLOWER
SO WILL NOT MENTION ANY PRECIP FOR SUNDAY AFTERNOON.  THE GFS IS
DRY...THE NAM AND GEM REGIONAL BRING IT INTO OUR AREA AND THEY ALSO
LINGER SOME PRECIP INTO MONDAY.  THE EUROPEAN MODEL HINTS SOME
PRECIP MAY MOVE THIS FAR NORTH...BUT LITTLE MORE THAN A TRACE.  FOR
NOW WILL CONTINUE A 20 PERCENT POPS ALONG AND SOUTHEAST OF A
WASHINGTON TO INDY LINE SUNDAY NIGHT.

IN THE EXTENDED MODELS HAVE TRENDED A LITTLE SLOWER WITH NEXT COLD
FRONT WITH IT NOW MOVING IN LATE TUESDAY OR EARLY WEDNESDAY. WILL
DELAY ONSET OF PRECIP A LITTLE WITH THIS FORECAST.

MODELS BRING A STRONG UPPER TROUGH ACROSS OUR REGION THANKSGIVING
DAY. BUT THERE IS SOME DISAGREEMENT ON HOW MUCH COLD AIR GETS
TRAPPED INTO THIS SYSTEM.  THE GFS HAS 1000-850 MB THICKNESS OF 1285
METERS WHICH WOULD BE MOSTLY SNOW.  THE EUROPEAN HAD 1000-850 MB
THICKNESS IN THE LIQUID CATEGORY.  THE GEM NW MODEL HINTED LOW LEVEL
THICKNESS MAY DROP BELOW CRITICAL THICKNESS BY THANKSGIVING. FOR NOW
WILL MENTION LOW CHANCES OF MIXED PRECIP FROM INDY N AND EAST
THANKSGIVING AND SLIGHT CHANCES OF RAIN SHOWERS ELSEWHERE.  ALSO
WENT A LITTLE COLDER THAN HPC TEMPERATURES THIS PERIOD.

AN AREA OF HIGH PRESSURE WILL MOVE EAST ACROSS THE TENNESSEE AND
OHIO VALLEYS FRIDAY AND DRY AND FAIR WEATHER WILL BE THE RULE THEN.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH
UPDATE...TDUD

000
FXUS63 KIND 210100
AFDIND

AREA FORECAST DISCUSSION...CORRECTION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
800 PM EST FRI NOV 20 2009

.AVIATION...DISCUSSION FOR 210000Z TAF ISSUANCE.
HIGH PRESSURE WILL CONTROL INDIANAS WEATHER THROUGH THE TAF PERIOD.
WITH THIS STABLE SYSTEM TAFS WILL START OUT VFR. THE CLEAR
SKIES...LIGHT TO CALM WINDS AND SOME LOW LEVEL MOISTURE REMAINING
WILL CAUSE FOG TO DEVELOP AFTER 05Z-08Z DECREASING VISIBILITIES TO
MVFR. THEY WILL CONTINUE TO DECREASE TO IFR AFTER 10Z. AREAS OF LIFR
IN FOG IS POSSIBLE. THE SUNNY SKIES ON FRIDAY HAVE ALLOWED SURFACE
LEVELS TO DRY OUT SOME SO THE FOG WILL NOT BE AS WIDESPREAD AS
FRIDAY MORNING. THE CLEAR SKIES WILL CAUSE THE FOG TO QUICKLY BURN
OFF AFTER SUNRISE. BY 15Z VFR CONDITIONS CAN BE EXPECTED.

&&

.DISCUSSION...
UPPER LOW HAS MOVED WELL TO OUR EAST AND WEAK HIGH PRESSURE OVER THE
MID MISSISSIPPI VALLEY WILL DOMINATE OUR WEATHER THROUGH EARLY
SUNDAY AND POSSIBLY LONGER DEPENDING ON FAR NORTH A DEVELOPING LOW
PRESSURE SYSTEM OVER TEXAS MOVES LATE SUNDAY OR MONDAY.

THE MAIN WEATHER CHALLENGES INCLUDE CHANCE OF FOG LATE
TONIGHT...RAIN CHANCES SUNDAY NIGHT THROUGH MIDWEEK AND
PRECIPITATION TYPE IF IT OCCURS FOR THANKSGIVING DAY.

THE GROUND HAS HAD A HALF A DAY TO DRY OUT AND FOG SHOULD NOT BE
NEARLY AS EXTENSIVE AS LAST NIGHT.  BUT CURRENT CROSS OVER
TEMPERATURES ARE NEAR FORETASTED LOW AND WITH LIGHT WINDS AND MOSTLY
CLEAR SKIES WILL ADD MENTION OF PATCHY FOG. NAM SOUNDING INDICATES
SC IS POSSIBLE LATER TONIGHT AND THERE IS A SC DECK CURRENTLY OVER
NORTH CENTRAL ILLINOIS.

QUIET AND UNEVENTFUL WEATHER WILL BE THE RULE SATURDAY AND SATURDAY
NIGHT AS WEAK HIGH PRESSURE MOVES EASTWARD ACROSS OUR REGION.

THE MODELS ARE VERY WISHY WASHY ON WHETHER MOISTURE FROM THE LOW IN
OUR SOUTH WILL TRACK THIS FAR NORTH.  THEY ARE ALL A LITTLE SLOWER
SO WILL NOT MENTION ANY PRECIP FOR SUNDAY AFTERNOON.  THE GFS IS
DRY...THE NAM AND GEM REGIONAL BRING IT INTO OUR AREA AND THEY ALSO
LINGER SOME PRECIP INTO MONDAY.  THE EUROPEAN MODEL HINTS SOME
PRECIP MAY MOVE THIS FAR NORTH...BUT LITTLE MORE THAN A TRACE.  FOR
NOW WILL CONTINUE A 20 PERCENT POPS ALONG AND SOUTHEAST OF A
WASHINGTON TO INDY LINE SUNDAY NIGHT.

IN THE EXTENDED MODELS HAVE TRENDED A LITTLE SLOWER WITH NEXT COLD
FRONT WITH IT NOW MOVING IN LATE TUESDAY OR EARLY WEDNESDAY. WILL
DELAY ONSET OF PRECIP A LITTLE WITH THIS FORECAST.

MODELS BRING A STRONG UPPER TROUGH ACROSS OUR REGION THANKSGIVING
DAY. BUT THERE IS SOME DISAGREEMENT ON HOW MUCH COLD AIR GETS
TRAPPED INTO THIS SYSTEM.  THE GFS HAS 1000-850 MB THICKNESS OF 1285
METERS WHICH WOULD BE MOSTLY SNOW.  THE EUROPEAN HAD 1000-850 MB
THICKNESS IN THE LIQUID CATEGORY.  THE GEM NW MODEL HINTED LOW LEVEL
THICKNESS MAY DROP BELOW CRITICAL THICKNESS BY THANKSGIVING. FOR NOW
WILL MENTION LOW CHANCES OF MIXED PRECIP FROM INDY N AND EAST
THANKSGIVING AND SLIGHT CHANCES OF RAIN SHOWERS ELSEWHERE.  ALSO
WENT A LITTLE COLDER THAN HPC TEMPERATURES THIS PERIOD.

AN AREA OF HIGH PRESSURE WILL MOVE EAST ACROSS THE TENNESSEE AND
OHIO VALLEYS FRIDAY AND DRY AND FAIR WEATHER WILL BE THE RULE THEN.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

PUBLIC...JH
AVIATION...SH

000
FXUS63 KIWX 210055
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
630 PM EST FRI NOV 20 2009

.AVIATION...(00Z UTC)
PATCHY STRATOCU...SC... FIELD WILL PRESENT CHALLENGES FOR
FORECASTING FOG DEVELOPMENT OVERNIGHT. EXPECT SC OVER NORTHERN
ILLINOIS TO SLOWLY DRIFT EASTWARD. MODELS SEEM TO STRUGGLE WITH
MOISTURE FIELD OVER NORTHERN INDIANA BUT LOCATION OF THE CLOUD LAYER
WILL BE CRITICAL OVERNIGHT. SOME FOG MAY DEVELOP AFTER 06Z TIMEFRAME
BUT SHOULD BE LIMITED BY SC...CLEARING AND FOG BURNOFF EXPECTED BY
14Z.

&&

.SHORT TERM.../TONIGHT THROUGH SATURDAY NIGHT/...
MUCH MORE OPTIMISTIC SHORT TERM PERIOD WITH HIGH TEMPS RETURNING
TO ABOVE NORMAL FOR SATURDAY. UPPER LOW THAT SPOILED THE WORK WEEK
IS CENTERED OVER SOUTHERN ONTARIO WHILE A FOLLOWUP SHTWV IS MOVING
INTO ILLINOIS. THIS FEATURE IS NOT GENERATING AS MUCH CLOUD COVER
AS ANTICIPATED EXCEPT OVER THE NE THIRD OF THE CWA WHERE IT HAS
MOVED INTO AN AREA OF MOISTURE LEFT BEHIND BY RETREATING UPPER
LOW. MODELS INDICATE THIS AREA OF ENHANCED RH THROUGH THE MID
LEVELS TO REMAIN OVERNIGHT AND INTO SATURDAY. WHILE THIS WILL
CURTAILS AN OTHERWISE IDEAL RAD COOLING SETUP COOLING/MOISTURE
STILL SUFFICIENT FOR OVERNIGHT FOG TO DEVELOP. SOUTH OF THICKER
CLOUD POTENTIAL WHERE SKIES SHOULD BE CLEARER WENT SLIGHTLY COOLER
WITH LOWS BUT THIS ALSO SETS UP MORE SIGNIFICANT FOG DEVELOPMENT.

SATURDAY WILL SEE ABV NORMAL TEMPS AS MIXING TO MODEL AVERAGED H92
TEMPS YIELDS HIGHS IN THE MID 50S.  GRIDS ARE SLIGHTLY COOLER THAN
THIS IN THE NORTHEAST WHERE MORE CLOUDS ARE EXPECTED AND WARMER IN
SOUTHERN AREAS WHERE TEMPS TODAY ARE REACHING 52-54 DESPITE COOLER
TEMPS ALOFT.

&&

.LONG TERM.../SUNDAY THROUGH FRIDAY/...

GENERAL SOUTHWEST FLOW REGIME OF LATE WILL BEGIN TO BREAK DOWN
DURING IN THE PERIOD. STRONG LL TEMPERATURE GRADIENT OVER THE
NORTHERN PAC WILL SET THE STAGE FOR A SUBTLE PATTERN CHANGE AS A
WEAK SFC WAVE NEAR THE EASTERN ALEUTIANS INTERACTS WITH A
STRENGTHENING UPPER LEVEL IMPULSE PUSHING OVER THE WESTERN
ALEUTIANS. ORIENTATION OF THE STRENGTHENING UPPER LEVEL JET WILL
SUPPORT DEEPENING OF THE AFOREMENTIONED UPPER LEVEL TROUGH WITH
INCREASING NW LL FLOW SUPPORTING AMPLE CAA...WITH TROUGHING EXPECTED
INTO THE WESTERN US BY EARLY NEXT WEEK. GIVEN THE POSITION OF THE
EXPECTED UPPER LEVEL JET OVER THE WESTERN CONUS WITH WIDESPREAD
DOWNSTREAM RIDGING ALREADY IN PROGRESS...EXPECT A PERIOD OF UPPER
LEVEL TROUGH DIGGING AS DEPICTED IN GEM AND ECMWF PROGS. DEGREE OF
DIGGING AND AFFECT ON THE PROGRESSIVE NATURE OF THE FLOW IS STILL
YET TO BE DETERMINED. IN ADDITION...CLOSING OF THE UPPER LEVEL WAVE
AS SUPPORTED IN NEARLY ALL DETERMINISTIC RUNS LENDS CREDENCE TO A
SEMI SPLIT FLOW PATTERN WITH THE BULK OF CAA RESIDING WELL NORTH OF
THE REGION. A SHIFT TO AT OR BELOW NORMAL TEMPERATES IS WARRANTED IN
DAYS 5-7. HOWEVER...THE VERY COLD PROGS IN THE GFS MAY BE TOO
AGGRESSIVE GIVEN CONCERNS ON SYSTEM EVOLUTION. BOTTOM LINE...HAVE
HELD CLOSER TO ECMWF NUMBERS...WITH A HEAVY TREND TO CLIMO. THIS
WILL CERTAINLY SUPPORT A CHANCE OF MIXED PRECIP LATE IN THE PERIOD.
HOWEVER...AT THIS POINT ACCUMULATING SNOWFALL LOOKS TO REMAIN NORTH
OF THE REGION AT THIS POINT AS THE FLOW WILL REMAIN SOMEWHAT
PROGRESSIVE.

SUNDAY THROUGH MONDAY...GOMEX DISTURBANCE WILL EJECT TOWARD THE
EASTERN OH VALLEY WITH AN INCREASE IN HIGH AND MID LEVEL CLOUDS
EXPECTED. WARM PROFILES WILL SUPPORT TEMPS IN THE 50S...WITH THE
AMOUNT OF INSOLATION DICTATING THE DEGREE OF T RISE HEAVILY. A FEW
SOLUTIONS SUGGEST THE FAR EASTERN FA COULD GET CLIPPED BY A PERIOD
OF LIGHT RAIN LATE IN THE DAY. HOWEVER...CONCERNS ON DRY PROFILES
AND TRACK VARIABILITY DOES NOT WARRANT POP ADDITION. EXPECT ANOTHER
MILD DAY ON MON...WITH INCREASING MID AND HIGH CLOUDS LIKELY
LIMITING SHARPER T RISES IN DISTURBED SW FLOW.

TUE-FRI...PREFER A TREND TO AN ECMWF SOLUTION GIVEN PREFERRED
HANDLING OF UPPER LEVEL MOMENTUM FIELDS. SLOWER ARRIVAL OF THIS
SYSTEM IS PREFERRED GIVEN NORTHERN STREAM WAVE SPLIT AND GIVEN LIKELY
CLOSING OF THE UPPER LEVEL CIRCULATION. MAIN CHANGES TO THE GRIDS TO
REFLECT THIS SOLUTION WERE TO WARM TEMPS TUE AND SLIGHTLY WED...AND
SHIFT SNOW MENTION TO THE THE LATER PERIODS. WITH CONTINUOUS SIGNALS
SUPPORTING PROLONG NEGATIVE MSLP AND HEIGHT ANOMALIES OVER THE GREAT
LAKES THROUGH THE PERIOD...FEEL IT WAS PRUDENT TO RAISE POPS TO 40
IN MANY PERIODS GIVEN CLIMO NUMBERS ACROSS THE FA NOW AT OR ABOVE 30
PER 12 HOUR.

&&



.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...LUDINGTON
LONG TERM...JC
AVIATION...SABONES