FXUS63 KIND 010831
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
330 AM EST TUE DEC 1 2009

.DISCUSSION...
SATELLITE INDICATED CLEAR SKIES WERE THE RULE ACROSS THE MID 
MISSISSIPPI VALLEY...OHIO VALLEY AND INDIANA. A BROAD AREA OF HIGH 
PRESSURE WAS CENTERED OVER WESTERN TENNESSEE.  WATER VAPOR IR 
INDICATED AN UPPER LOW OVER EASTERN CANADA AND JUST SOUTH OF NEW 
MEXICO AND A STRONG SHORT WAVE JUST NORTH OF MONTANA.

MAIN FOCUS WILL BE PRECIPITATION CHANCES...TIMING AND TYPE WEDNESDAY 
INTO THURSDAY.

FOR TODAY...CLEAR WILL BE THE RULE AS THE SURFACE HIGH OVER WESTERN 
TENNESSEE TRACKS TOWARDS THE CAROLINAS. WILL GO ON THE HIGH END OF 
MOS TEMPERATURES TODAY WITH PLENTY OF SUNSHINE AND WARM ADVECTION.

MODEL CONSENSUS STILL DEVELOPS A SURFACE OVER THE WESTERN GULF LATER 
TODAY AND THEN MOVE IT NORTH NORTH EAST INTO THE OHIO VALLEY BY 00Z 
THURSDAY AND TO NEAR BUFFALO BY 12Z THURSDAY. THE OPERATIONAL GFS IS 
STILL THE FARTHEST EAST WITH THE SURFACE LOW TRACK TAKING IT ACROSS 
FAR EASTERN KENTUCKY WHILE THE NAM IS THE FARTHEST WEST TRACKING IT 
ACROSS SOUTHEAST INDIANA AND WESTERN OHIO. THE CANADIAN...EUROPEAN 
AND UK MODELS ARE CLOSER TO THE NAM SCENARIO...BUT JUST A TAD EAST 
OF THE NAM.  MOST OF THE GFS ENSEMBLE MEMBERS ARE WEST OF THE 
OPERATIONAL GFS.  A MODEL BLEND SEEMS REASONABLE AND WILL GO NEAR OR 
JUST SLIGHTLY WEST OF THE SREF.

THE MODELS ARE A LITTLE FASTER IN BRINGING PRECIPITATION OUR WAY.  
WILL START RAIN A LITTLE SOONER THAN PREVIOUS FORECAST...BUT NOT 
QUITE AS FAST AS CURRENT MODELS AS I HAVE SEEN MANY TIMES THEM BEING 
A BIT FAST WITH SYSTEMS MOVING OUT OF THE SOUTHWEST.  THE SHORT WAVE 
MOVING OUT OF SOUTHWEST CANADA AMPLIFIES INTO A MAJOR UPPER LOW AS 
IT MOVES INTO THE UPPER MIDWEST AND THE UPPER LOW OVER THE SOUTHWEST 
IS EJECTED ACROSS THE OHIO VALLEY.

TONIGHT WILL START OUT CLEAR...THEN CLOUDS MOVING IN LATE TONIGHT.  
WILL GO CLOSE TO MOS TEMPERATURES.  ON WEDNESDAY WILL UNDERCUT MOS 
TEMPERATURES A LITTLE AS PRECIPITATION MOVES IN.  NAM SURFACE 
TEMPERATURES ONLY MAX OUT IN THE 40S AND EVAPORATIONAL COOLING FROM 
PRECIPITATION WILL KEEP TEMPERATURES A LITTLE COOLER.

PRECIPITATION WILL START OUT AS RAIN AND CHANGE OVER TO SNOW BY 06Z 
THURSDAY OVER WESTERN SECTIONS AND IN THE EAST BY 09Z-10Z. SNOW 
AMOUNTS UP TO AN INCH ARE POSSIBLE ACROSS OUR NORTHWEST WHERE CHANGE 
OVER OCCURS QUICKER.  MOST OTHER AREAS WILL BE A HALF INCH OR LESS 
WITH THE GROUND BEING WARM AND TEMPERATURES BARELY REACHING 
FREEZING.

ONLY MINOR CHANGES MADE THURSDAY INTO FRIDAY. SCATTERED VERY LIGHT 
SNOW SHOWERS OR FLURRIES WILL BE THE RULE THURSDAY AND WILL KEEP A 
CHANCE OF FLURRIES THURSDAY NIGHT AND FRIDAY MAINLY NORTH.  THE 
COLDEST AIR SO FAR THIS SEASON WILL MOVE ACROSS OUR AREA THURSDAY 
INTO SATURDAY.  PREVIOUS FORECAST UNDERCUT MOS TEMPERATURES A LITTLE 
AND THIS STILL LOOKS GOOD.

FINALLY FAIR WEATHER WILL BE THE RULE THIS WEEKEND AS HIGH PRESSURE 
MOVES ACROSS OUR REGION.  MODELS HINT THAT ANOTHER SYSTEM FROM THE 
SOUTHWEST MAY AFFECT OUR WEATHER BY THE MIDDLE OF NEXT WEEK. 

&&

.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.

&&

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

&&

$$

PUBLIC...JH
AVIATION...CP