Severe Thunderstorm Warning 58, NWS Milwaukee, WI

AREA FORECAST DISCUSSION...UPDATED TO ADD MARINE/AVIATION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
415 AM CDT THU JUN 12 2008

.DISCUSSION...FCST FOCUS ON CONVECTIVE TRENDS TODAY AND TONIGHT AND
FROM THAT...HEAVY RAIN AND SVR POTENTIAL.

WATER VAPOR LOOP SHOWS SIMPRESSIVE CIRCULATION CENTER VCNTY ERN MT
INTO DAKOTAS. STG CONVECTION ACRS IA/ERN MN AND WRN WI STILL ON THE
MOVE BUT INSTABILITY DROPS OFF CONSIDERABLY INTO CNTRL AND ERN WI.
THINK SOME OF THIS ACTION WILL AT LEAST CLIP OUR WRN CWA THIS MRNG
BUT EXPECT SOME WEAKENING OF THESE STORMS THE DEEPER EASTWARD THEY
GO INTO WI. WILL START FFA A BIT EARLIER IN THE FAR WRN CNTYS TO
ACCOUNT FOR 88-D TRENDS.

BIG QUESTION THEN BECOMES HOW MUCH CAPE CAN WE GET GOING WHEN THE
HEAVY HITTING DYNAMICS AND LOW LEVEL FORCING ARRIVE THIS AFTN AND
THIS EVENING. OBVIOUSLY A LOT OF TIME FOR THESE CLOUDS AND PCPN TO
ERODE. IF ENUF HEATING CAN GET GOING TODAY...DESTABILAZATION WILL
TAKE PLACE AND WITH THE 0-6KM SHEAR PLENTIFUL...COULD SEE SIGNIFICANT
UPTICK IN SVR POTENTIAL. H5 WIND MAX OF 60-70KTS PUNCHES IN FROM
THE SW WITH H8 WIND MAX OF 40-50 KTS FROM SSW. SFC WINDS NOT
OVERLY STRONG...SO LOOKING AT DECENT SPEED AND DIRECTIONAL SHEAR. SPC
SHOWING APPRECIABLE CONCERN ABOUT ROTATING STORMS BUT ALSO CONCEDE
THERE IS A QUESTION REGARDING AMOUNT OF CAPE/INSTABILITY.

THE MAIN CONCERN GIVEN ALL OF THE ONGOING FLOODING PROBLEMS WILL BE
THE HEAVY RAINFALL...AND OF COURSE SOME OF THIS POTENTIAL HINGES ON
THE AFOREMENTIONED CLEARING UNCERTAINTIES...BUT LOW LEVEL DEW POINT
AXIS PROGGD TO SHIFT EASTWARD INTO WI TODAY WITH SFC WRM FNT LIFTING
BACK TO THE NORTH. PRECIPITABLE WATER VALUES AND PRECIPITATION
EFFICIENCIES PUSH 2 AND H8 DEWS GET INTO THE TEENS. VERY IMPRESSIVE
JET DVRG ASSOC WITH H2-H3 RRQ JET SHOOTING NE AROUND UPPER SYS. LOW
LEVEL FRONTOGENETICAL FORCING PEAKS IN THE 00-06Z TIME FRAME TNGT.
CERTAINLY POTENTIAL TO REALIZE 1-2 INCH TOTALS GIVEN THE JUICY AMS
IN PLACE WITH STG LIFT. THE VARIABLE THAT IS THE BIG QUESTION WILL
BE THE AVBL CAPE WITH SFC BASED HEATING. NEVERTHELESS WITH ALL OTHER
PARAMETERS FAVORABLE WILL KEEP THE FFA INTACT.

FRIDAY LOOKS POTENTIALLY INTERESTING WITH SFC TROUGH STILL NOTED IN
THE AREA AND SWIFT SW UPPER JET STILL PLACE AROUND THE STG CANADIAN
VORTEX. H5 SHORT WAVE ACTION COULD IMPINGE ON AN ENVIRONMENT THAT
MAY SUPPORT CAPES EXCEEDING 1K. GOING TSTM CHC LOOKS GOOD FOR FRIDAY.

WEAK TROUGH STILL IN PLACE SATURDAY...ESP ON NAM AND ECMWF. THIS
COMBINED WITH SLIGHTLY CYCLONIC AND SWIFT H5 FLOW AND H5 TEMPS IN
THE MINUS TEENS...COULD LEAD TO SCT SHRA/TSRA SATURDAY.

GFS SHOWING A SIGGY NW FLOW TYPE EVENT ON SUNDAY INTO SUNDAY
EVENING WITH CAPES BETWEEN 3 AND 4K AND LI/S DOWN TO -8. ECMWF HINTS
AT SOMETHING ALONG THESE LINES BUT KEEPS ALL QPF OUT OF CWA. FOR
NOW WILL KEEP CHC IN PLACE SUNDAY INTO SUNDAY EVENING TO ACCOUNT
FOR THIS POSSIBILITY GIVEN THE STRENGTH OF H5 WNW FLOW AND
PROXIMITY OF DECENT INSTABILITY.

&&
10

.AVIATION...WITH EXPECTED MOIST AIRMASS...CIGS AND VSBYS IN THUNDER
LIKELY TO DROP BELOW VFR FOR A TIME. PERIOD OF STRONGEST
THUNDERSTORMS LATE AFT/EARLY EVE AT KMSN AND IN THE
EVENING/OVERNIGHT AT ERN TAF SITES.

&&

.MARINE...STRENGTHENING PRESSURE GRADIENT FINALLY TURNING WINDS TO
THE SOUTHEAST. WOULD EXPECT WINDS TO INCREASE OVER THE NEARSHORE
WATERS SHORTLY.  WIND GUSTS MAY REACH SMALL CRAFT ADVISORY LEVELS
LATER THIS MORNING...ESPECIALLY AT KSBM CMAN.  HOWEVER BAGGIER
PRESSURE GRADIENT DEVELOPS THIS AFTERNOON...SO NOT ENOUGH CONFIDENCE
THAT SC.Y CONDITIONS WILL LAST LONGER THAN ONE OR TWO HOURS AT THIS
POINT. WILL ADD CAUTIONARY STATEMENT TO NEARSHORE FORECAST.  MARINE
INTERESTS SHOULD PLAN ON REMAINING IN HARBOR OR SEEKING HARBOR EARLY
THIS AFTERNOON AS STRONG THUNDERSTORMS ARE EXPECTED LATER ON.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH FROM NOON CDT TODAY THROUGH FRIDAY MORNING
FOR      WIZ046-047-051-052-057>060-063-064-066-068>072.

     FLASH FLOOD WATCH FROM 7 AM CDT THIS MORNING THROUGH FRIDAY
     MORNING FOR WIZ056-062-067.

     FLASH FLOOD WATCH THROUGH FRIDAY MORNING FOR WIZ065.

LM...NONE.
&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1215 PM CDT THU JUN 12 2008

WIZ046-047-051-052-056>060-062>072-131200-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
1215 PM CDT THU JUN 12 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS WILL MOVE THROUGH PORTIONS OF
SOUTHERN WISCONSIN EARLY THIS AFTERNOON. THEY ARE EXPECTED TO REMAIN
BELOW SEVERE LEVELS. HOWEVER...THEY MAY DEPOSIT RAINFALL OF ONE
QUARTER TO ONE HALF INCH.

THUNDERSTORMS ARE EXPECTED TO REDEVELOP AND AFFECT SOUTHERN
WISCONSIN LATER THIS AFTERNOON AND TONIGHT. SOME THUNDERSTORMS MAY
BECOME SEVERE...PRODUCING HAIL UP TO ONE INCH IN DIAMETER...AND
DAMAGING WIND GUSTS TO 70 MPH. A FEW TORNADOES ARE POSSIBLE.

IN ADDITION...THE THUNDERSTORMS ARE EXPECTED TO PRODUCE WIDESPREAD
HEAVY RAINFALL OF ONE TO TWO INCHES. THIS WILL RENEW THE FLASH FLOOD
THREAT...AND AGGRAVATE THE MANY FLOODING PROBLEMS REMAINING ACROSS
SOUTHERN WISCONSIN FROM THE PREVIOUS WEEKEND HEAVY RAINFALL.
THUS...A FLASH FLOOD WATCH REMAINS IN EFFECT ACROSS ALL OF SOUTHERN
WISCONSIN THIS AFTERNOON AND TONIGHT.

MANY LAKES...RIVERS AND STREAMS REMAIN WELL ABOVE FLOOD STAGE...OR
ARE FORECAST TO EXCEED FLOOD STAGE. A FEW SITES HAVE OR WILL EXCEED
RECORD STAGES. SEE OUR ADVANCED HYDROLOGIC PREDICTION SERVICES
INTERNET PAGE FOR DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS ON FRIDAY...AND AT TIMES
SATURDAY THROUGH MONDAY.

MANY RIVERS AND STREAMS WILL REMAIN AT OR ABOVE FLOOD STAGE THROUGH
NEXT TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY LATER THIS AFTERNOON AND TONIGHT.

LMZ643>646-131200-
SHEBOYGAN TO PORT WASHINGTON WI-
PORT WASHINGTON TO NORTH POINT LIGHT WI-
NORTH POINT LIGHT TO WIND POINT WI-
WIND POINT WI TO WINTHROP HARBOR IL-
1215 PM CDT THU JUN 12 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT

THUNDERSTORMS ARE LIKELY LATER TODAY...WITH PERIODS OF THUNDERSTORMS
TONIGHT. SOME THUNDERSTORMS MAY BECOME SEVERE...WITH LARGE HAIL TO
ONE INCH IN DIAMETER...AND DAMAGING WIND GUSTS TO 50 KNOTS. AN
ISOLATED WATERSPOUT IS POSSIBLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THERE IS A CHANCE OF THUNDERSTORMS FRIDAY...AND AT TIMES SATURDAY
THROUGH MONDAY.

WOOD
WWW.WEATHER.GOV/MILWAUKEE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1038 AM CDT THU JUN 12 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1026 AM     FLOOD            BELLEVILLE              42.86N 89.54W
06/12/2008                   DANE               WI   OTHER FEDERAL

            THE DAM AT BELLEVILLE HAS BOTH GATES OPEN AND THE
            MEASURED AMOUNT IS 2 FEET AND 8 INCHES AT REFERENCE POINT
            1007. HEAVY RAIN...LIGHTNING AND THUNDER IS CURRENT.

&&

GD