Damaging Wind and Lightning Strike in Wisconsin, August 6, 2007

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
953 PM CDT MON AUG 6 2007

.UPDATED DISCUSSION...HEAVY RAIN POTENTIAL TONIGHT.

PRECIPITABLE WATER ANALYSIS SHOWS VALUES OF 2.0 INCHES PLUS PUSHING
INTO SWRN AND FAR SRN SECTIONS OF CWA...EXTENDING SWD INTO IL WITH A
SECOND POCKET OF 2 INCH PLUS PW/S OVER WRN IA. 850 MB WIND PROFILER
AND VAD WIND PROFILES SHOW NOSE OF 25-30 KT WINDS MOVING INTO SW WI
TRIGGERING SHOWERS AND THUNDERSTORMS FROM THE DELLS THRU MADISON TO
JANESVILLE AND SW. SHORT WAVE THAT CROSSED SRN NEBRASKA LATE THIS
AFTERNOON HAS HELPED TO DEVELOP COMPLEX IN W CNTRL IA.

REPORTS SHOW INDIVIDUAL CELLS THAT HAVE DEVELOPED ON LLJ AND IN
REGION OF ELEVATED CAPE NORTH OF SFC WRM FNT HAVE PRODUCED 2 INCHES
OF RAIN IN RICHLAND COUNTY...AND ARE PUSHING EWD INTO CWA AS LLJ IS
EXPECTED TO LEAN TOWARD SRN WI OVERNIGHT.

MOISTURE TRANSPORT VECTORS AND STORM MOTION INDICATE COMPLEX IN IA
COULD PUSH ACROSS SRN WI LATE TONIGHT INTO TUESDAY MORNING...BUT
OUTFLOW BOUNDARIES FROM CURRENT AND PREVIOUS CONVECTION HAVE HELD
WRM FNT TO THE SOUTH WITH HIGHER ELEVATED CAPE VALUES NEAREST THE
CWA CURRENTLY RUNNING FROM THE QUAD CITIES TO THE CHICAGO AREA. THIS
MAY CAUSE COMPLEX TO TRACK FARTHER SOUTH PER NEW 00Z NAM
GUIDANCE...BUT TOO CLOSE TO CANCEL FLASH FLOOD WATCH.

REST OF DISCUSSION FROM EARLIER TODAY.

NO QUESTION IT IS VERY MOIST OUT THERE. SATELLITE DERIVED
PRECIPITABLE WATER SHOWS A PUDDLE OF HIGH PW/S OVR IA...NRN MO AND
CNTRL/NRN IL...IN EXCESS OF 2. CONVECTION ACROSS ERN NEB MOVING
INTO THIS AND IS BEING HELPED IN PART BY A MID LEVEL S/W PROGD TO
TRACK THROUGH HERE OVERNIGHT. CURRENT TRENDS OF CONVECTION OUT
WEST APPEARS TO BE A BIT FASTER THAN THE MODELS. HAVE GONE MORE
WITH THE NAM TONIGHT AS THE GFS IS SUFFERING FEEDBACK. H8 FAR TOO
INTENSE ON THE GFS AND LIKELY IS RESULTING IN A STRONGER SFC LOW
WITH A MORE NORTHERLY AND PRODUCTIVE TRACK OF THE QPF.

CONVECTION TONIGHT SHOULD BECOME MORE FOCUSED ALONG THE FNTL BNDRY
TO THE SOUTH THIS EVENING THEN ROLL IN HERE AS THE LLJ LEANS THIS
WAY AHEAD OF THE WEAK LOW CENTER...AND THE S/W COMES ACROSS.
MODEL PW/S ARE 2 TO 2.25IN TONIGHT. MIXING RATIOS CLIMB TO 8 TO
9G/KG UP TO NEAR H7...VERY MOIST. FEEL PRETTY CONFIDENT OF ANOTHER
HVY RAIN EPISODE TONIGHT. GIVEN VERY HEAVY RAIN FROM SATURDAY
NIGHT...3 TO 5 INCHES FM ROCK UP TO SAUK COUNTY...GROUND IS
SATURATED. ACTUALLY...PHONE CALLS TODAY IN THE BARNEVELD AREA HAVE
PRODUCED SOME 9 TO 10 INCH AMOUNTS FROM SATURDAY NIGHT. THIS NEXT
ROUND OF PCPN WILL SEE FAR MORE RUNOFF THAN THE LAST EPISODE. AFTER
COORDINATION WITH ARX AND LOT...HAVE DECIDED TO PUT UP A FLASH FLOOD
WATCH FOR THE WRN AND SRN TIER OF THE CWA FROM MIDNIGHT THROUGH 3 PM
TUESDAY.

AS SYSTEM MOVES EAST ON TUESDAY...THERE IS SOME THREAT FOR
REDEVELOPMENT TUESDAY AFTN AS VRY HIGH DWPNTS WILL LINGER BEHIND
WITH POSSIBLE OLD OUTFLOW BNDRYS AS PSBL TRIGGERS. NOT TOO
CONFIDENT THAT WILL HAPPEN. IT WILL LIKELY TAKE TOO LONG FOR
THINGS TO RECOVER BEFORE DIURNAL TRENDS AND A LITTLE RETURN OF
DRIER AIR LIMIT ANY REDEVELOPMENT.

&&

.AVIATION...STATIONARY FRONT OVER NRN IL WILL SLOWLY MOVE INTO SRN
WI TNT AND TUE. VERY MOIST AND UNSTABLE AIR WILL PREVAIL OVER THE
REGION WHILE A WEAK LOW PRESSURE AREA MOVES EWD ALONG THE FRONT.
THIS WILL GENERATE A STRONG THUNDERSTORM COMPLEX...MOSTLY LIKELY
AFTER 06Z AND LASTING WELL INTO TUE MORNING AND POSSIBLY INTO EARLY
AFTERNOON. BESIDES THE TSTORMS...THE MOIST AIRMASS WILL LEAD TO
AREAS OF MVFR CIGS AND VSBYS TNT INTO TUE.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM MIDNIGHT CDT TONIGHT THROUGH TUESDAY
AFTERNOON FOR WIZ056-062-063-067>072.

&&

DAVIS/REM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
610 PM CDT MON AUG 6 2007

WIZ046-047-051-052-056>060-062>072-072315-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
610 PM CDT MON AUG 6 2007

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

.DAY ONE...TONIGHT

A FLOOD WARNING IS IN EFFECT FOR THE EAST BRANCH OF THE PECATONICA
RIVER NEAR BLANCHARDVILLE IN LAFAYETTE COUNTY THROUGH THIS
EVENING. THE WARNING WILL LIKELY BE EXTENDED.

SCATTERED THUNDERSTORMS OVER FAR SOUTHERN WISCONSIN WILL BECOME
MORE WIDESPREAD OVER ALL OF SOUTH CENTRAL AND SOUTHEAST WISCONSIN
OVERNIGHT.

NO SEVERE WEATHER IS EXPECTED...BUT SOME OF THE STORMS WILL
PRODUCE LOCALLY HEAVY RAINFALL IN AREAS THAT RECEIVED 2 TO 5
INCHES OF RAIN SATURDAY NIGHT INTO SUNDAY...WITH LOCALLY HIGHER
AMOUNTS. A FLASH FLOOD WATCH IS IN EFFECT TONIGHT INTO TUESDAY FOR
LOCATIONS ALONG AND SOUTHWEST OF A WISCONSIN DELLS TO MADISON
LINE...AND FOR THE COUNTIES ALONG THE WISCONSIN ILLINOIS BORDER.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A FLASH FLOOD WATCH IS IN EFFECT UNTIL TUESDAY AFTERNOON
FOR LOCATIONS ALONG AND SOUTHWEST OF A WISCONSIN DELLS TO MADISON
LINE...AND FOR THE COUNTIES ALONG THE WISCONSIN ILLINOIS BORDER.

THERE WILL BE A CHANCE OF THUNDERSTORMS TUESDAY THROUGH THURSDAY
NIGHT. THERE IS A SLIGHT RISK OF SEVERE STORMS TUESDAY AND TUESDAY
NIGHT. THE MAIN THREATS WILL BE DAMAGING WINDS AND LOCALLY HEAVY
RAIN.

HEAT INDEX VALUES ARE EXPECTED TO RISE TO 95 TO 100 DEGREES
TUESDAY AND WEDNESDAY AFTERNOONS OVER PORTIONS OF SOUTHERN
WISCONSIN.

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION SHOULD NOT BE
NEEDED...BUT RAINFALL REPORTS WOULD BE APPRECIATED.

LMZ643>646-665-072315-
SHEBOYGAN TO PORT WASHINGTON-
PORT WASHINGTON TO NORTH POINT LIGHTHOUSE-
NORTH POINT LIGHTHOUSE TO WIND POINT-
WIND POINT TO WINTHROP HARBOR ILLINOIS-
WISCONSIN ADJACENT OPEN WATERS OF LAKE MICHIGAN TO MID LAKE-
610 PM CDT MON AUG 6 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS OVER FAR SOUTHERN LAKE MICHIGAN WILL
BECOME MORE WIDESPREAD OVERNIGHT. NO SEVERE WEATHER IS
EXPECTED...HOWEVER HEAVY DOWNPOURS OF RAIN WILL LIMIT VISIBILITIES
TO 1/4 MILE OR LESS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THERE WILL BE A CHANCE OF THUNDERSTORMS TUESDAY THROUGH THURSDAY
NIGHT. THERE IS A SLIGHT RISK OF SEVERE STORMS TUESDAY AND TUESDAY
NIGHT. THE MAIN THREAT WILL BE DAMAGING WINDS.

REM
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