FXUS63 KIND 012255
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
555 PM EST TUE DEC 1 2009

.AVIATION...DISCUSSION FOR THE 02/00Z TAFS.

GULF COAST LOW PRESSURE SYSTEM WILL BEGIN TO PUSH 
NORTH/NORTHEASTWARD TONIGHT...PASSING THROUGH THE MID/UPPER OHIO 
VALLEY TOMORROW AFTERNOON AND EVENING. RAIN SHOWERS ARE ANTICIPATED 
TO BEGIN ACROSS THE SITES BY MID TO LATE MORNING TOMORROW. ALONG 
WITH THESE SHOWERS...MIDLEVEL CLOUDS WILL PUSH IN...GENERALLY AT OR 
ABOVE 5000 FEET EARLY...BEFORE FALLING TO ABOUT 3500 FEET BY MID 
AFTERNOON. AT THE MOMENT...CEILINGS ARE EXPECTED TO REMAIN 
VFR...EXCEPT FOR IND WHERE 30 HOUR TAF PERIOD SHOULD SEE A DECREASE 
TO MVFR CEILINGS AND POSSIBLY HIGH END IFR AFTER 00Z TOMORROW NIGHT. 
THIS IS LIKELY AT ALL SITES...BUT BEYOND THE TAF PERIOD FOR 
LAF/HUF/BMG.

VISIBILITY IMPACTS ARE LIKELY TO FLUCTUATE WITH SHOWERS...AND HAVE 
HINTED AT THIS WITH 6SM BR AFTER MIDDAY TOMORROW.

WINDS WILL BE STEADILY BACKING FROM THE SOUTH TO THE NORTH/NORTHEAST 
DURING THE PERIOD...AND A FEW GUSTS AT OR BELOW 20 KNOTS ARE 
POSSIBLE FOR A PERIOD FROM ABOUT 18-00Z TOMORROW. SUSTAINED WINDS 
WILL PEAK AROUND 7-12 KNOTS AT THAT TIME AS WELL.

&&

.SHORT TERM...
SATELLITE IMAGERY IS SHOWING CLEAR SKIES ACROSS THE GREAT LAKES
REGION...OHIO VALLEY...AND ALL OF NEW ENGLAND AS HIGH PRESSURE
REMAINS ANCHORED OVER THOSE PORTIONS OF THE COUNTRY. HOWEVER...TWO
DIFFERENT SYSTEMS ARE MOVING THROUGH THE NORTHERN PLAINS AND
SOUTHERN PLAINS/SOUTHEAST.

THE MAIN FOCUS OF FORECAST WILL BE THE SECOND SYSTEM MENTIONED
ABOVE...WHICH IS CURRENTLY PRODUCING SHOWERS AND THUNDERSTORMS
ACROSS THE SOUTH. THIS SYSTEM IS SCHEDULED TO MOVE INTO THE OHIO
VALLEY ON WEDNESDAY NIGHT.

FORECAST HAS CHANGED SIGNIFICANTLY IN REGARD TO SNOW ACCUMULATIONS
WITH WEDNESDAY/S SYSTEM. FIRST...GFS CONTINUES TO BRING THE SYSTEM
TO THE EAST...NAM/UKMET/ECMWF ARE LEANING TOWARD THE SOUTHEAST
INDIANA AREA...AND THE CANADIAN IS IN THE MIDDLE. SO...LEANING
TOWARD SOUTHEAST IN/WESTERN OH TRACK. HOWEVER...IT WILL NOT BE A
HUGE IMPACT ON PRECIPITATION LINES BECAUSE TEMPERATURES WILL BE
TOO WARM. LATEST FORECAST SOUNDINGS AND ALL MODELS NOW HAVE COLD
AIR MOVING IN CLOSER TO THU 12Z INSTEAD OF THU 06Z...WHICH WAS
ORIGINALLY EXPECTED. THIS WILL BE TOO MUCH LATE FOR ANY SNOW
ACCUMULATION. THE SYSTEM/BEST FORCING WILL BE TOO FAR TO THE
NORTHEAST BY THAT POINT. THE ONLY CHANCE FOR ANY SNOW WILL BE OVER
THE FAR NORTHWEST PORTIONS OF FORECAST AREA IF THE COLD AIR IS IN
PLACE WHEN IN TIME FOR WRAPAROUND MOISTURE.

SO...RAIN IS EXPECTED TO MOVE IN BY EARLY AFTERNOON ON WEDNESDAY
AND CONTINUE INTO THE NIGHT. THE MAIN CHANGE IS AFTER
MIDNIGHT. THE TIME PERIOD BETWEEN THU 06Z AND 12Z WAS WHEN THE
BULK OF SNOW WOULD HAVE FALLEN IF IT WAS COLD ENOUGH. BUT...THAT
IS NOW A RAIN/SNOW MIXTURE. AS MENTIONED EARLIER...IT WOULD
TRANSITION TO SNOW AROUND 12Z...BUT THE ONLY MOISTURE LEFT WILL BE
WHAT/S ON BACKSIDE OF LOW.

AS FAR AS TEMPERATURES...WENT WITH MID 30S FOR TONIGHT. MODELS
WERE IN DECENT AGREEMENT...EXCEPT FOR NAM...WHICH WAS TOO COLD.
TOMORROW...MODELS ARE STRUGGLING TO COME INTO AGREEMENT AS SYSTEM
MOVES IN. LEANED TOWARD COOLER SIDE AS CLOUD COVERAGE INCREASES.
TOMORROW NIGHT...TRENDED TOWARD HIGHER SIDE OF GUIDANCE SINCE ALL
MODELS ARE IN AGREEMENT. THURSDAY...WENT WITH A BLEND. THURSDAY
NIGHT...COLD EVERYWHERE.

.LONG TERM...
NO MAJOR WEATHER PROBLEMS AS HIGH PRESSURE WILL DOMINATE THE
WEATHER. ON FRIDAY THE FLOW FROM THE NORTHWEST WILL REMAIN
UNSTABLE ENOUGH FOR SOME FLURRIES, THE SOUNDINGS DO SHOW HIGH
MOISTURE FROM 850 TO 750 MB ESPECIALLY DURING THE AFTERNOON. ONLY
TIME AFTER THAT FOR ANY HIGH MOISTURE IS ON MONDAY IN THE MID AND
HIGH LEVELS. WITH THE FLOW CONTINUING FROM THE NORTH WILL GO FOR
LITTLE CHANGE IN TEMPERATURES.

&&

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

&&

$$

SHORT TERM...TDUD
LONG TERM...SH
AVIATION...NIELD