Hail and Damaging Wind in Wisconsin, September 29, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
830 PM CDT SUN SEP 29 2002

...THUNDERSTORMS RAPIDLY DEVELOPING...

GEOSTROPHIC SURFACE WIND ANALYSIS AT 21Z SHOWED THE LOW LEVEL JET
DEVELOPMENT WOULD OCCUR OVER IOWA AND INTO SOUTHERN MINNESOTA.  THIS
IS NOW COMING TO FRUITION GIVEN THE INCREASING LOW LEVEL FLOW /UP TO
40 KNOTS/ DEPICTED BY THE PROFILER DATA AT 850 MB.

THE SUBSEQUENT FORCING ALONG THE WARM FRONT OVER SOUTHERN MINNESOTA
AND NORTHERN IOWA IS CAUSING RAPID DEVELOPMENT OF THUNDERSTORMS.
THESE STORMS SHOULD REMAIN ELEVATED...SINCE THE CAP IS TOO STRONG
FOR SURFACE BASED STORMS /CIN 300-400 J/KG/.  THUS...THE MAIN SEVERE
WEATHER THREAT SHOULD BE LARGE HAIL NORTH OF THE WARM FRONT.

.LSE...NONE.

KRC

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-032>034-
041>044-053>055-061-300500-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LA CROSSE WI
843 PM CDT SUN SEP 29 2002

HAZARD - SEVERE THUNDERSTORMS WITH LARGE HAIL.

TIMING - 900 PM TO 300 AM.

LOCATION - NORTHEAST IOWA...SOUTHEAST MINNESOTA...CENTRAL AND
SOUTHWEST WISCONSIN.

DISCUSSION - THUNDERSTORMS ARE DEVELOPING RAPIDLY OVER SOUTHERN
MINNESOTA AND NORTHERN IOWA.  THESE STORMS ARE DEVELOPING IN THE
AREA WHERE STRONG LOW LEVEL WINDS ARE INTERACTING WITH A WARM
FRONT.  THESE LOW LEVEL WINDS WILL BE INCREASING OVER THE NEXT FEW
HOURS...THEN THEY WILL MOVE TO THE EAST.  THIS WILL CAUSE THE STORMS
TO INCREASE IN STRENGTH AND AREAL COVERAGE...EVENTUALLY EVOLVING
INTO A COMPLEX OF THUNDERSTORMS.  THE STORMS WILL BE MOVING INTO
SOUTHEAST MINNESOTA AND NORTHEAST IOWA AFTER 900 PM...AND INTO
WISCONSIN BEFORE MIDNIGHT.

SPOTTER INFORMATION - SPOTTER ACTIVATION MAY BE NEEDED.

KRC