FXUS63 KIND 010435
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1135 PM EST MON NOV 30 2009

.AVIATION...DISCUSSION FOR 6Z TAFS.
HIGH PRESSURE TO THE SOUTH WILL KEEP SKIES CLEAR EXCEPT PERHAPS FOR 
A FEW CIRRUS THROUGH THE PERIOD. DEWPOINTS IN THE 20S AND WINDS 
STAYING IN THE 5-10+ KT RANGE WILL PRECLUDE ANY FOG FORMATION. WINDS 
OUT OF THE SOUTHWEST WILL SHIFT TO THE SOUTHEAST BY TUESDAY EVENING 
AND DECREASE IN SPEED AS THE PRESSURE GRADIENT DECREASES.

&&

.UPDATE...
THE WARM AIR ADVECTION IS SLOW TO TAKE PLACE. DEW POINTS IN THE MID 
20S. WITH CLEAR SKIES AND WINDS BECOMING LIGHT HAD TO LOWER 
TEMPERATURES SOME. THE TEMPERATURE DROP SHOULD SLOW AS WARMER AIR 
BEGINS TO MOVE IN.

&&

.SHORT TERM...
SATELLITE IMAGERY IS CURRENTLY SHOWING A LONG COLD FRONT EXTENDING
FROM NEW ENGLAND TO SOUTHERN TEXAS...RESULTING IN SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE EASTERN THIRD OF THE COUNTRY.
ELSEWHERE...HIGH PRESSURE IS DOMINATING MOST OF THE PLAINS AND THE
WEST...WHILE ANOTHER COLD FRONT TRIES TO MOVE INTO THE PACIFIC
NORTHWEST.

THE FOCUS OF THE FORECAST IS THE PRECIPITATION TYPE AND
ACCUMULATIONS WITH THE SYSTEM MOVING IN ON WEDNESDAY.

MODELS ARE COMING INTO BETTER AGREEMENT WITH THE TRACK OF THE
SYSTEM GOING ACROSS THE TENNESSEE VALLEY. THE GFS CONTINUES TO
BRING THE SYSTEM FURTHER SOUTH...BUT IT COMES INTO LINE WITH THE
GEM/ECMWF/NAM/UKMET RATHER QUICKLY. DECENT FRONTOGENESIS AND
Q-VECTOR CONVERGENCE IN THE MID-LEVELS WOULD PROVIDE AMPLE FORCING
FOR SOME ACCUMULATIONS. HOWEVER...THE COLDEST AIR WILL MOVE IN
AFTER THE BEST FORCING. AS A RESULT...KEPT SNOW AMOUNTS AT AN INCH
OR LESS FOR NOW. IN ADDITION...THERE WILL BE STRONG WARM AIR
ADVECTION TOMORROW...SO THE WARM GROUND WILL ALSO HINDER SNOW
ACCUMULATIONS.

AS FAR AS TIMING...KEPT IT THE SAME. PRECIPITATION WILL FALL IN
THE FORM OF RAIN ON WEDNESDAY AFTERNOON...TRANSITION TO A
SNOW/RAIN MIX DURING THE EVENING HOURS...AND THEN FINALLY TURN TO
SNOW AFTER MIDNIGHT.  

AS FAR AS TEMPERATURES...MODELS ARE IN GOOD AGREEMENT UP UNTIL THE
SYSTEM MOVES IN ON WEDNESDAY. SO...WENT WITH A BLEND THROUGH
TOMORROW NIGHT. RADIATIONAL COOLING TONIGHT SHOULD BRING
TEMPERATURES DOWN TO THE FREEZING MARK ACROSS MOST OF THE
AREA...THE ONLY CAVEAT WOULD BE LINGERING CLOUDS ACROSS THE EAST.
TOMORROW...STRONG WARM AIR ADVECTION AND SOUTHWEST WINDS AHEAD OF
THE SYSTEM WILL RESULT IN HIGHS IN THE UPPER 50S OVER SOUTHERN
INDIANA. TOMORROW NIGHT...STUCK WITH GUIDANCE. WEDNESDAY...WENT ON
THE LOW SIDE OF GUIDANCE DUE TO CLOUDS BUILDING INTO THE AREA.
WEDNESDAY NIGHT...COLD AIR WILL START FILTERING IN BEHIND THE LOW
PRESSURE SYSTEM...EVENTUALLY BOTTOMING OUT BELOW FREEZING.

.LONG TERM...
FOR THE EXTENDED...COLD CYCLONIC FLOW WILL REMAIN IN PLACE ACROSS
CENTRAL INDIANA FROM THURSDAY THRUOGH SATURDAY AS THE STRONG LOW
OVER THE NORTHEAST CONTINUES TO SLOWLY PULL NORTHEAST. GIVEN THIS
HAVE KEPT CHANCE FOR WRAP AROUND SNOW SHOWERS IN THE FORECAST ON
THURSDAY AND TRENDED TOWARD FLURRIES ON THURSDAY NIGHT AND FRIDAY
GIVEN THE COLD AIR AND THE FLOW. ALSO GIVEN THE CYCLONIC FLOW HAVE
TRENDED SKY GRIDS ON THE MORE CLOUDY SIDE. ECMWF AND GFS DISAGREE
ON HOW FAST THE COLD POOL WILL MOVE OUT ON IN THE SUNDAY/MONDAY
TIME RANGE. GFS IS ABOUT 24 HOURS FASTER. FOR NOW WILL SPILT THE
DIFFERENCE AND KEEP SUNDAY AND MONDAY DRY ALONG WITH THE SLOW
WARMING TREND THAT MODELS DO AGREE UPON. OVERALL...GIVEN THE COLD
FLOW HAVE TRENDED COOLER THAN GUIDANCE ON TEMPS EXPECT WARM ON
SATURDAY MORNING LOWS WHERE MIDDLE TEENS SEEM A BIT OVERDONE.

&&

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

&&

$$

SHORT TERM...TDUD
LONG TERM...JP
AVIATION...CP
UPDATE...SH