Hail and Damaging Winds in Indiana, September 23, 2001

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
320 PM EST SUN SEP 23 2001

MAIN CHALLENGE FOR THIS FCST WL BE TRW CHANCES TODAY AND THEN WHEN TO
MENTION CLRG AND HOW COOL IT WL GET AS A CD FNT MOVES ACRS THIS AFT
AND A SHARP TROF FOLLOWS ON MONDAY. H20 VAPOR IMAGERY WAS SHOWING A
SHARP UPR TROF FM NERN MN TO XTRM SERN SD IN GENERAL AGREEMENT WITH
THE MODELS. MEANWHILE...IR PIX AND SFC OBS SHOWING AREA OF MID CLDS
SPREADING E ACRS THE FA WITH CD CLD TOPS TO -65 DEGREES CELSIUS ACRS
ERN KS...NRN MO AND SRN IA ASSOCIATED WITH A LG AREA OF CONVECTION
ALONG AND AHEAD OF A CD FNT FM SRN MN TO WRN IA TO SWRN KS.

MODELS HAVE BEEN INCONSISTENT IN TIMING AND STRENGTH OF THE
AFOREMENTIONED UPR TROF AND EVENTUAL CLOSED LOW. HOWEVER...THEY WERE
IN PRETTY GOOD AGREEMENT THIS TIME AROUND AND ARE ESPECIALLY CLOSE ON
THE MN LVL RH AND UVM PROGS AND SEE NO REASON TO DEVIATE MUCH FM
THEM. THE ONE THING THAT STOOD OUT...HOWEVER...WAS THE MODELS NOT
GENERATING MUCH QPF. BELIEVE WITH STRENGTH OF SYS...CAPES PROGGED TO
1000 J/KG THIS AFT...NICE JET STREAK ENHANCEMENT AND FAVORABLE TIME
OF DAY OF THE FROPA...PRECIP AMOUNTS SHOULD BE MUCH GREATER THAN QPF
PROGS INDICATE. ONLY THING FAVORING THE MODELS WOULD BE THE FAST
MOVEMENT OF THE CD FNT WITH SUCH NICE UPR PUSH. AT ANY RATE...WOULD
EXPECT SQUALL-LINE DEVELOPMENT WITH SVR THREAT PER THE SPC DAY1
DISCUSSION ACRS NWRN SECTIONS OF THE FA BY EARLY AFT. PRETTY GOOD
SHEAR INDICATED BY THE MODELS FM 1000-700 MB AT 18Z WITH 10 KTS AT
H1000 AND 40 KTS AT H7 AND DIRECTIONAL SHEAR AT GREATER THAN 45
DEGREES. AREA ALSO IN RR QUAD OF 80 KT JET STREAK ACRS NWRN INDIANA
BY THIS EVE WITH H5 WINDS FM 40-50 KTS. MODELS THEN SPREAD THE BEST
LIFT/DEEP MOIST INTO SERN ZONES BY 00Z THIS EVE JUST AHEAD OF THE CD
FNT. MODELS THEN PUSH A DRY SLOT ACRS TNGT...BUT COMBO OF UPR TROF TO
THE W AND PLNTY OF MOIST AT AND BLO H8 SHOULD KEEP THE CLDS AROUND
AND ALSO POPS GOING. LIKELY POPS OF THE MOS LOOK A BIT MUCH THOUGH
AND WL GO WITH CHC POPS INSTEAD. CLOSED LOW DVLPS LATE MON AND SHIFTS
E INTO OH BY EVE. DESPITE LOW MOS POPS...THINK AT LEAST MRNG CHC POPS
WARRANTED WITH UPR TROF MOVING THROUGH. BY AFT...COLUMN DRIES NICELY
BUT STILL ENOUGH MOIST/LIFT NE TO KEEP SMALL POPS GOING AND CU RULE
WOULD FAVOR KEEPING MOSTLY CLDY SKIES GOING. SKIES SHOULD FINALLY CLR
MON NGT AS THE UPR LOW PULLS E INTO ERN OH.

EXTENDED LOOKS PRETTY QUIET AS SFC HIGH PRES RIDGE ACRS THE MSP VLY
GRADUALLY WORKS ITS WAY E AND COLUMN DRIES EVEN MORE.

MOS TEMPS AGREE VERY WELL TODAY AND APPEAR REASONABLE. PREFER WARMER
FWC TNGT WITH CLDS HANGING AROUND. MOS NUMBERS AGAIN VERY CLOSE ON
MONDAY AND SEEM TO GRASP MAGNITUDE OF CD AIR INTRUSION. MOS AGAIN
CLOSE MON NGT AND APPEARS REASONABLE WITH CLRG SKIES AND CD AIRMASS.

.IND...NONE.
KOCH