FXUS63 KIND 252253
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
555 PM EST FRI DEC 25 2009

.AVIATION...DISCUSSION FOR 26/00Z TAFS
STRONG SURFACE LOW WILL REMAIN AROUND IOWA FOR THE NEXT 24 HOURS 
BEFORE IT BEGINS TO MORE OFF TO THE NORTHEAST.  PRESENTLY MVFR 
CEILINGS WERE THE RULE WITH A STRONG SOUTH SOUTHWEST FLOW AND GUSTS 
TO 25 KNOTS ACROSS OUR REGION.

CONDITIONS MAY IMPROVE A LITTLE TONIGHT AS DRY SLOT DOMINATE OUR 
WEATHER.  EXCEPT FOR KLAF CEILINGS AT MOST OTHER TAFS MAY RISE TO 3 
THOUSAND FEET AND SOME BREAKS IN CLOUDS MAY OCCUR OVER SOUTHERN 
SECTIONS.  KLAF SHOULD SEE LESS IMPROVEMENT AND SCATTERED LIGHT SNOW 
SHOWERS OR FLURRIES WILL BE THE RULE OVERNIGHT.

WINDS WILL DECREASE SLIGHTLY OVER THE NEXT 24 HOURS AS THE GRADIENT 
DECREASES A LITTLE.  LIGHT SNOW SHOWERS WILL BECOME MORE LIKELY 
SATURDAY AS THE DRY SLOT SHIFTS A LITTLE TO THE EAST AND WEAK UPPER 
DISTURBANCES ROTATES AROUND THE LOW PRESSURE SYSTEM.

&&

.PREVIOUS DISCUSSION...

BIGGEST PROBLEM IS TEMPERATURES. 

MAV LOOKS HIGH TO ME FOR MOST OF FORECAST PERIOD. MET LOOKS BETTER 
BUT STILL NEEDS TO BE CUT. 

LOOKING AT TEMPERATURES UPSTREAM DONT SEE 30S UNTIL YOU GET TO 
ARKANSAS AND ITS SUNNY THERE. ABOVE 30 WILL BE CHALLENGING TOMORROW 
SINCE WE ARE APT TO BE CLOUDY. 

SECOND REASON I DONT LIKE MOS TEMPS IS THE MODELS CONCUR WITH 
THICKNESSES PLUNGING OVER INDIANA BEGINNING OVERNIGHT. MAV TEMPS 
DONT SEEM TO PICK UP ON THIS VERY WELL AND MET DOES NOT AFTER 
TONIGHT....BUT ITS CONSISTENT WITH THE COLD TEMPERATURES THAT SEEM 
TO BE HEADING TOWARD THIS. 

BOTTOM LINE IS I CAN LIVE WITH MET TONIGHT...BUT AFTER THAT I WILL 
CUT IT ABOUT 3 DEGREES INTO MONDAY. 

AT LEAST IT WILL BE COLD ENOUGH SO ANY PRECIPITATION WILL BE SNOW. 
MODELS AGREE WE WILL BE IN DRY SLOT MOST OF TONIGHT WITH MOISTURE 
INCREASING AT MID LEVELS BUT BOUNDARY LAYER STAYING DRY TOWARD. I 
EXPECT FLURRIES FLURRIES DEVELOPING IN MOIST LAYER AND MAKING IT TO 
SURFACE...BUT AGREE WITH GUIDANCE ABOUT LOW CHANCE OF MEASURABLE.

SATURDAY COULD BE GOOD FOR SNOW SHOWERS WITH CYCLONIC FLOW OVR 
LAKES...UNSTABLE BOUNDARY LAYER...AND SOME Q VECTOR DIVERGENCE 
ALOFT. SOME PLACES WILL TRACE OUT...OTHERS WILL MEASURE...BUT THINK 
MOST REPRESENTATIVE FCST WILL BE SNOW SHOWERS LIKELY.

MODELS AGREE FAIRLY WELL ABOUT PRIMARY FIELDS SATURDAY NIGHT THROUGH 
SUNDAY. TO THE EXTENT THEY DIFFER LIKED GFS WHICH WAS MUCH CLOSER TO 
SREF. FOR THE MOST PART ACCEPT MAV POPS SATURDAY NIGHT INTO 
MONDAY...BUT WILL BUMP UP TO 50 PERCENT SUNDAY WITH MODELS SHOWING 
FAIRLY GOOD QVECTOR DIVERGENCE ALOFT. 

BUFKIT SUPPORTS SOME GUSTS SATURDAY WHICH MAKES SENSE AS COLD 
ADVECTION ALOFT PROMOTES DOWNWARD MIXING. CLOUDY TO MOSTLY CLOUDY 
THROUGH SUNDAY NIGHT UNDER CYCLONIC FLOW. MAY GET SOME BREAKS MONDAY 
AS HIGH STARTS TO BUILD IN. 

&&

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

&&

$$

PUBLIC...KWIATKOWSKI
AVIATION...JH