Severe Thunderstorm Warning 58, NWS Milwaukee, WI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
215 PM CDT TUE JUN 6 2006

.DISCUSSION...FORECAST FOCUS ON THUNDERSTORM CHANCES TODAY AND
TONIGHT.

NAM ETA/WRF BOTH VERIFIED WELL WITH BAND OF MORNING SHOWERS
WEAKENING AS IT PUSHED OFF TO THE EAST.

FOR THIS AFTERNOON AND EVENING...MAIN PROBLEM IS ON HOW QUICK/OF IF
THE STRATO CUMULUS BECOMES SCATTERED SO INSTABILITY CAN INCREASE
AHEAD OF SHORTWAVE NEAR W TIP OF LAKE SUPERIOR.

IN THE UPPER LEVELS...AN ADVANCING JET  WILL MOVE SOUTHEAST INTO THE
UPPER MISSISSIPPI VALLEY THIS EVENING. LEFT FRONT QUAD TO AFFECT
MAINLY SOUTHEAST PORTION OF THE FORECAST AREA...WITH THE JET AXIS
BISECTING THE FORECAST AREA LATE TONIGHT.

PRECIPITABLE WATER VALUES 1.25 TO 1.5 INCHES WITH LOWER TO MID 60
DEWPOINTS. CURRENT RUC SOUNDINGS SHOW ENOUGH HEATING TO GENERATE
CAPES UP TO 1500 J/KG MAINLY ACROSS SOUTH CENTRAL WI...WITH MORE OF
A CAP ACROSS SOUTHEAST WISCONSIN THROUGH THE AFTERNOON.

BULK RICHARDSON NUMBERS IN THE AROUND 26 AND 0-3 KM STORM RELATIVE
HELICITY AROUND 150 M2/S2 ARE MARGINAL FOR SUPERCELLS. DRY MID LEVEL
AIR WILL ADVECT INTO SOUTHERN WI AS SHORTWAVE MOVES TOWARD MICHIGAN.
WET BULB ZERO HEIGHTS AROUND 9.5  THSD FT. EXPECT SCT STORMS TO
DEVELOP ALONG OR AHEAD OF THE SURFACE TROF LATER THIS AFT AND INTO
THE EVENING. WILL NOT MENTION SEVERE IN ZFP DUE TO MARGINAL WIND
SHEAR WHICH WILL LIMIT THE EXTENT AND SEVERITY...BUT SOME STORMS MAY
STILL BECOME SEVERE...AGAIN DEPENDING ON RECOVERY OF LOW LEVEL
TEMPERATURES.

DESPITE RATHER STEEP LOW LEVEL LAPSE RATES...DRY AIR...ESPECIALLY IN
MID LEVELS SHOULD KEEP THE FORECAST AREA DRY WEDNESDAY.

PREFER GFS WITH UPPER RIDGE WILL BUILD ACROSS THE PLAINS FOR WED/THU
WITH RIDGE OF SURFACE HIGH PRESSURE IN THE VICINITY THROUGH FRIDAY.
NAM SEEMS WAY TOO FAR NORTHEAST WITH DEVELOPING SURFACE LOW.

A MORE ZONAL FLOW LATER IN THE WEEKEND AND EARLY NEXT WEEK.
DEPENDING ON UPSTREAM OFFICES...LATEST GFS WOULD INDICATE SURFACE
HIGH TO DOMINATE INTO SATURDAY.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

HENTZ

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
745 AM CDT TUE JUN 6 2006

WIZ046-047-051-052-056>060-062>072-070900-
COLUMBIA-DANE-DODGE-FOND DU LAC-GREEN-GREEN LAKE-IOWA-JEFFERSON-
KENOSHA-LAFAYETTE-MARQUETTE-MILWAUKEE-OZAUKEE-RACINE-ROCK-SAUK-
SHEBOYGAN-WALWORTH-WASHINGTON-WAUKESHA-
745 AM CDT TUE JUN 6 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL
WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EVENING.
THERE IS A SLIGHT RISK THAT SOME OF THESE THUNDERSTORMS COULD BECOME
SEVERE. THE MAIN SEVERE WEATHER THREATS WILL BE LARGE HAIL AND
DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

MORE THUNDERSTORMS ARE POSSIBLE SATURDAY THROUGH MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING.

LMZ643>646-665-070900-
NORTH POINT LIGHTHOUSE TO WIND POINT-
PORT WASHINGTON TO NORTH POINT LIGHTHOUSE-
SHEBOYGAN WI TO PORT WASHINGTON-
WIND POINT TO WINTHROP HARBOR ILLINOIS-
745 AM CDT TUE JUN 6 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING.
THERE IS A SLIGHT RISK THAT SOME OF THESE THUNDERSTORMS COULD BECOME
SEVERE. THE MAIN SEVERE WEATHER THREATS WILL BE LARGE HAIL AND WIND
GUSTS IN EXCESS OF 30 KNOTS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

MORE THUNDERSTORMS ARE POSSIBLE SATURDAY THROUGH MONDAY.

MBK