000 
FXUS63 KIWX 250844
AFDFWA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
340 AM EST MON FEB 25 2002

MAIN WX PROB IS TUE STORM AND DIFFS IN MODELS.

CDFNT TO ENTER W CWFA ARND 12Z...CLEARING THE E COUNTIES ARND 00Z.
HWVR...CDFNT SLOWS GREATLY AS LO PRES DVLPS OVR THE TN VLY AND MOVS
NNE. ITS THERE...ARND 00Z TUE...THAT THE MODELS REALLY BEGIN TO
DIVERGE. PREFER AN ETA/NGM BLEND SINCE THE AVN SEEMS TOO FAR E AND
TOO WEAK WITH THE SFC LO. GIVEN THAT...LO PRES XPCTD TO MOV NNE TO
NEAR LUK BY 12Z TUE...CLE BY 18Z...AND ON TO TORONTO WITH 2NDRY FNT
BACK INTO IL.

1000-500 5400 LINE ENTERS NW CWFA ARND 22Z TDY AND MAKES IT ACRS
THE CWFA BY 09Z TUE AS THE LO IS SPINNING UP NEAR LUK. BIG QUESTION
MARK OVR SE ZONES AS ETA BRINGS COLD AIR THRU ENTIRE CWFA BUT NGM
KEEPS WARMER TEMPS INVOF THE LO AS IT MOVS NNE JUST E OF CWFA
TNGT/TUE MORN...SINCE NGM HAS THE LO ABT 100 MILES FARTHER NW THAN
THE ETA.  ZERO DEG 8H TEMP ENTERS NW CWFA ARND 18Z TDY. ETA TAKES IT
INTO OH BY 12Z TUE BUT NGM HANGS IT BACK FROM MARION TO BRYAN.
ALSO...NGM BRINGS DRY SLOT IN XTRM SE CWFA.

8H LO XPCTD TO BE IN C IN 12Z TUE...W OF TOL 18Z...AND OVR S LK
HURON 00Z WED. 5H LO FRM N MO AT 12Z...TO C IL AT 18Z...TRACKING ACRS
S/SE CWFA TUE AFTN TO FWA AT 00Z AND THEN INTO CANADA.

MSTR IS LIMITED THIS MRNG BUT INCREASES THIS AFTN AND REMAINS
PLENTIFUL THRU WED.

HVIEST PRECIP SHOULD FALL TUE MRNG. 1000-500 5310-5370 THICKNESS BAND
ACRS CWFA FRM 06Z TO 18Z TUE...1000-700 2830-2885 THICKNESS BAND ACRS
CWFA TUE MRNG. BEST MSTR/LIFT COMBO TUE MRNG AS WELL.

USING MODEL SNOW ACCUMS AND COOK METHOD AMOUNTS OF 4 TO 9 INCHES
POSSIBLE BY LATE TUE. THESE AMNTS WL HV TO BE TEMPERED SE THO DUE
TO LONGER PERIOD OF RA BEFORE CHANGEOVER TO SN.

THEN WE STILL HV TO WORRY ABT LES. FLO ABV LM TUE GNRLY FRM THE N...
SO ONLY MY WESTERNMOST COUNTIES TO FEEL THE EFFECTS. HWVR...FLO
BECOMES NW TUE NGT-WED SO MORE ACCUMS LIKELY NW THEN. INVERSION TUE
MRNG 3K TO 4K FT...BUT THEN RISES TO 6K-8K FT IN THE AFTN.

ALSO...WINDS WILL BE STRONG AND GUSTY TUE-WED...WHICH WL ONLY ADD
TO THE PROBS.

CONSIDERED UPPING TO A WARNING NW...BUT WITH WARNING CRITERIA WX
HOLDING OFF UNTIL TNGT...AND AFT COORD WITH OTHER OFFICES...WL KP
WATCH INSTEAD. ALSO...WL SPREAD WATCH FARTHER E. DAY SHIFT CAN THEN
LOOK AT THE LATEST DATA AND NAIL DOWN THE APPROPRIATE HEADLINES.

MOS TEMPS TOO COOL FOR MAXES TDY...OTRW LEANED TWD NGM.

MANY THANKS TO KILN...KGRR...KCLE...KIND...KDTX...AND KLOT FOR COORD.

EXTENDED...
5H TROF AT F60 ACRS ERN GRTLKS LIFTS NE BUT POLAR VORTEX THEN BEGINS
TO DROP S INTO HUDSON BAY. FAVOR LTST AVN/MRF AS ECMWF RAISES HGHTS
TOO FAST. STRONG SFC HI DROPS S INTO TX AND ANOTHER WK NRN STREAM
FNT LT FRI AND SNOW COVER SHOULD KEEP TEMP WARMUP SQUELCHED. LTST
MEX POINT IN THIS DIRECTION AND LOOKS REASONABLE. A WK CLIPPER ON
DY7 FOR CHC R-/S-.

.IWX...WINTER STORM WATCH TONIGHT THROUGH TUESDAY NIGHT ALONG AND
NORTHWEST OF A LINE FROM WINAMAC TO CENTREVILLE. WINTER STORM WATCH
LATE TONIGHT THROUGH TUESDAY EAST OF THE ABOVE LINE AND ALONG AND
WEST OF A LINE FROM HARTFORD CITY TO WAUSEON.

12/PBM