FXUS63 KIND 081650
AFDIND
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1145 AM EST TUE DEC 8 2009
.AVIATION...DISCUSSION FOR THE 18Z TAFS.
RADAR MOSAICS CONTINUE TO SHOW AREAS OF RAIN OVER SOUTHWEST INDIANA
AND WESTERN KENTUCKY ADVECTING NORTHEAST TOWARD THE TAF SITES.
ONGOING VFR CEILINGS EXPECTED TO DETERIORATE TO MVFR AS STRONG
ISENTROPIC LIFT BEGINS ACROSS THE AREA THIS AFTERNOON. FORECAST
SOUNDINGS BECOME DEEPLY SATURATED BY 00Z AND WITH STRONG LIFT
OCCURRING EXPECT WIDESPREAD PRECIPITATION ALONG WITH MVFR TO IFR
CONDITIONS THROUGH THE NIGHT.
STRONG WINDS WILL BE EXPECTED AS THE LOW DEEPENS AND MOVES TOWARD
THE GREAT LAKES ON WEDNESDAY MORNING. GIVEN THE STRENGTH OF THE
WINDS LOW LEVEL WIND SHEAR CANNOT BE RULED OUT EITHER...PARTICULARLY
AFTER 12Z WEDNESDAY. WITH CYCLONIC FLOW IN PLACE AND TIME HEIGHT
SECTIONS SHOWING SATURATED LOWER LEVELS CEILINGS AT 2000 FT TO 500
FT SEEM QUITE REASONABLE...MVFR TO IFR CEILINGS.
&&
.UPDATE...RADAR MOSAICS SHOW AN AREA OF RAIN SHOWERS MOVING INTO
SOUTHWEST INDIANA. AS TEMPERATURES HAVE RISEN A BRIEF PERIOD OF
FREEZING PRECIPITATION AT ONSET IS NOT LONGER EXPECTED AND HAVE
UPDATED GRIDS TO REMOVE MIX TYPE PRECIPITATION. TEMPERATURE FORECAST
LOOKS ON THE MARK GIVEN THE CLOUDS AND RAIN MOVING INTO THE AREA.
&&
.DISCUSSION...
IR SATELLITE IS SHOWING THE STRONG LOW PRESSURE SYSTEM THAT WILL
BRING BLIZZARD CONDITIONS TO PORTIONS OF THE PLAINS AND MIDWEST
IS CURRENTLY CENTERED OVER THE DESERT SOUTHWEST. AHEAD OF
IT...SNOW IS FALLING OVER MOST OF THE CENTRAL PLAINS.
THE MAIN FOCUS OF SHORT TERM FORECAST IS THE PRECIPITATION TYPE
ASSOCIATED WITH AFOREMENTIONED SYSTEM.
PRECIPITATION WILL START MOVING INTO SOUTHERN PORTIONS OF THE
FORECAST AREA THIS MORNING. TEMPERATURES WILL INITIALLY BE COLD
ENOUGH FOR A RAIN/SNOW MIX ACROSS THE SOUTHERN COUNTIES THROUGH
THE MORNING. CONFIDENCE IS LOW AROUND THE TUE 18Z TIME FRAME.
PRECIPITATION WILL START PUSHING INTO THE NORTHERN PORTIONS OF THE
FORECAST AREA...BUT THE QUESTION IS IF THE TEMPERATURES WILL STILL
BE COOL ENOUGH FOR SOME SNOW MIXED IN. IT WILL ALL DEPEND ON HOW
FAST THE PRECIPITATION REACHES THAT AREA. SO...CURRENTLY HAVE A
RAIN/SNOW MIX THROUGH THE EARLY AFTERNOON ACROSS NORTHWEST
COUNTIES. PRECIPITATION WILL THEN TRANSITION TO RAIN THIS
AFTERNOON...AND SHOULD LAST FOR THE MAJORITY OF THE EVENT. MODELS
ARE SHOWING TEMPERATURES INTO THE LOW 40S...FORECAST SOUNDINGS ARE
WELL ABOVE FREEZING...AND H850 TEMPS WILL BE IN EXCESS OF 6 C
TONIGHT. THE ONLY CHANCE FOR SNOW WILL BE AFTER WED 18Z WHEN THE
COLD AIR ON THE BACKSIDE MOVES INTO INDIANA. HOWEVER...MOST OF THE
PRECIPITATION WILL HAVE MOVED OUT OF THE AREA...BUT ANY LINGERING
PRECIPITATION WILL BE ALL SNOW. NO ACCUMULATIONS ARE EXPECTED. AS
FAR AS THUNDERSTORMS...WAS INITIALLY GOING TO INSERT ISOLATED
THUNDERSTORMS OVER SOUTHERN FORECAST AREA...BUT HAVE DECIDED TO
PULL THEM...JUST DON/T THINK TEMPERATURES WILL BE WARM ENOUGH.
A HIGH WIND WATCH REMAINS IN EFFECT FROM WEDNESDAY MORNING THROUGH
LATE WEDNESDAY NIGHT AS TIGHT PRESSURE GRADIENT PASSES OVER THE
REGION. SUSTAINED WIND SPEEDS WILL RANGE BETWEEN 25 AND 35 MPH WITH
GUSTS OVER 50 MPH.
AS FAR AS TEMPERATURES...MODELS ARE IN GOOD AGREEMENT FOR MOST OF
THE FORECAST PERIOD. TRENDED AT HIGHER END OF GUIDANCE FOR
TOMORROW/TOMORROW NIGHT DUE TO STRONG WARM AIR ADVECTION. THE COLD
AIR WILL FILTER INTO THE FORECAST AREA ON WEDNESDAY NIGHT. THE
OUTLYING MODEL WAS THE CANADIAN...WHICH BROUGHT LOWS INTO THE
SINGLE DIGITS. ALL OTHER MODELS ARE FORECASTING TEENS...SO WENT
WITH A BLEND OF THE GFS/ECMWF.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM WEDNESDAY MORNING THROUGH LATE WEDNESDAY
NIGHT FOR INZ021-028>031-035>049-051>057-060>065-067>072.
&&
$$
PUBLIC...TDUD
AVIATION...JP
UPDATE...JP
