Severe Thunderstorm Warning 119, NWS Milwaukee, WI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
300 PM CDT WED JUL 19 2006

.DISCUSSION...FORECAST FOCUS ON SEVERE WEATHER AND HEAVY RAIN POTENTIAL
TONIGHT.

SEVERE MCS THAT MOVED THROUGH MINNESOTA THIS MORNING HAS WEAKENED
INTO MAINLY RAIN. THIS AREA IS CURRENTLY MOVING SLOWLY EAST ACROSS
THE WESTERN PORTION OF THE FORECAST AREA. MORE SEVERE STORMS
FORMED TO THE SOUTH OF THIS MCS IN NORTHEAST IOWA...WHICH MOVED
SOUTHEAST INTO EASTERN IOWA AND NORTHWEST ILLINOIS.

MAIN FORECAST CHALLENGE IS DETERMINING IF MORE CONVECTION WILL
MOVE INTO THE FORECAST AREA LATER THIS EVENING AND OVERNIGHT...AND
SEVERE/HEAVY RAIN POTENTIAL. WRF MODEL HAD A REASONABLE SPATIAL
DEPICTION OF THE MCS THIS MORNING...ALTHOUGH ITS TIMING WAS WAY TOO
SLOW IN MOVING IT EAST AND SOUTHEAST THROUGH THE REGION. THE WRF
AND THE RUC BOTH SHOW NEW CONVECTION INITIATING IN NORTHERN IOWA
AROUND 00Z THURSDAY...NEAR THE SURFACE WARM FRONT AND LOW LEVEL
JET NOSE INTERSECTION. THE WRF THEN DEVELOPS ANOTHER MCS...AND
TAKES IT SOUTHEAST ACROSS EASTERN IOWA INTO NORTHWEST ILLINOIS BY
12Z THURSDAY...MISSING SOUTHERN WISCONSIN.

IN CONTRAST...THE GFS DEVELOPS THE CONVECTION MUCH FURTHER NORTH
IN MINNESOTA...TAKING IT SOUTHEAST ACROSS THE FORECAST AREA DURING
THIS TIME. THE LATEST 12Z HIGH RESOLUTION WRF MODEL ALSO DEVELOPS
CONVECTION OVER NORTHERN IOWA...BUT TAKES IT DUE EAST INTO THE
FORECAST AREA BY 06Z THURSDAY. PREFER THE WRF/HIGH RESOLUTION WRF
OVER THE GFS WITH THIS SCENARIO...AS THEY SEEMED TO HAVE A BETTER
HANDLE ON SURFACE AND UPPER FEATURES...AND THE CONVECTION THIS
MORNING.

HOWEVER...THE USUAL MODEL PROBLEMS WITH HANDLING CONVECTION CONTINUES
TO PRESENT SOME UNCERTAINTY. IF THE MCS DOES MOVE INTO THE FORECAST
AREA...THE SOUTHWEST HALF OF THE FORECAST AREA WOULD PROBABLY HAVE
THE BEST CHANCE. SO...WILL LOWER POPS SLIGHTLY TO THE 60 TO 70
RANGE FOR TONIGHT.

SEVERE WEATHER IS STILL POSSIBLE...IN THE FORM OF A FORWARD PROPAGATING
MCS AND/OR DERECHO. ELEVATED CAPES OF 2500 TO 4000 J/KG...AND 0-6KM
SHEAR VALUES OF 40 TO 50 KNOTS ARE EXPECTED. THE STRONG CAPPING
INVERSION IN THE LOW LEVELS...CIN VALUES OF 200 TO 250 J/KG...WILL
AGAIN BE A LIMITING FACTOR. HOWEVER...IF A SEVERE MCS/DERECHO DOES
FORM TO THE WEST...THE LARGE CIN WOULD NOT PREVENT IT FROM MOVING
EAST THROUGH THE FORECAST AREA. PRECIPITABLE WATER VALUES OF 2.00
INCHES...SOMETIMES HIGHER...WILL ALSO MEAN THE POTENTIAL OF HEAVY
RAINFALL...DESPITE THE EXPECTED PROGRESSIVE NATURE OF ANY MCS.

ANY CONVECTION SHOULD MOVE OUT OF THE FORECAST AREA THURSDAY
MORNING. HIGH PRESSURE RIDGE THEN MOVES INTO THE NORTHERN PLAINS
FOR THURSDAY NIGHT INTO FRIDAY...BRINGING COOLER AND LESS HUMID
CONDITIONS.

EXTENDED RANGE MODELS HAVE A MORE AMPLIFIED LONGWAVE TROUGH OVER
THE GREAT LAKES REGION...WIH A SUBSEQUENTLY MORE AMPLIFIED RIDGE
OVER THE WEST FOR THE WEEKEND. SHORTWAVE TROUGHS EMBEDDED IN THE
FLOW OVER THE WESTERN GREAT LAKES REGION MAY INTERACT WITH
UNSTABLE AIRMASS SATURDAY NIGHT AND SUNDAY...SO WILL GO WITH 30
POPS FOR THIS PERIOD. UPPER FLOW BECOMES MORE ZONAL BY
MIDWEEK...AND RETREATS A BIT NORTHWARD. STILL...SOUTHWEST WINDS
SHOULD USHER A WARMER AIRMASS INTO THE REGION. POSSIBLE WARM
FRONTAL BOUNDARY OVER THE REGION MAY BRING PRECIPITATION
CHANCES...SO WILL GO WITH 30 POPS AT TIMES DURING THIS PERIOD.

&&

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

WOOD

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1000 PM CDT WED JUL 19 2006

WIZ046-047-051-052-056>060-062>072-200900-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
1000 PM CDT WED JUL 19 2006

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

.DAY ONE...REST OF TONIGHT

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF
SOUTH CENTRAL WISCONSIN...GENERALLY ALONG AND WEST OF A DELLS...LAKE
MILLS TO MONROE LINE. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS
OVER THE REMAINDER OF SOUTHERN WISCONSIN. DAMAGING WINDS AND LARGE
HAIL ARE POSSIBLE. SOME OF THE THUNDERSTORMS MAY PRODUCE HEAVY RAIN
AND COULD PRODUCE URBAN AND SMALL STREAM FLOOD PROBLEMS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A CHANCE OF LINGERING THUNDERSTORMS THURSDAY MORNING.
THERE IS ALSO A CHANCE OF THUNDERSTORMS SATURDAY...AND FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT.

LMZ643>646-665-200900-
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-
1000 PM CDT WED JUL 19 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN.

.DAY ONE...TONIGHT

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHEAST
WISCONSIN AND THE ADJOINING WATERS OF LAKE MICHIGAN TONIGHT.
DAMAGING WINDS AND LARGE HAIL ARE POSSIBLE...AS WELL AS LIGHTNING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A CHANCE OF LINGERING THUNDERSTORMS THURSDAY MORNING.
THERE IS ALSO A CHANCE OF THUNDERSTORMS SATURDAY AND FROM SUNDAY
NIGHT THROUGH MONDAY NIGHT.

REM

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1117 PM CDT WED JUL 19 2006

WIZ046-047-051-052-056>060-062>072-200500-
COLUMBIA-DANE-DODGE-FOND DU LAC-GREEN-GREEN LAKE-IOWA-JEFFERSON-
KENOSHA-LAFAYETTE-MARQUETTE-MILWAUKEE-OZAUKEE-RACINE-ROCK-SAUK-
SHEBOYGAN-WALWORTH-WASHINGTON-WAUKESHA-
1117 PM CDT WED JUL 19 2006

...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR MOST OF
SOUTHERN WISCONSIN UNTIL 7 AM CDT...

A THUNDERSTORM IN NORTHWESTERN IOWA COUNTY...JUST SOUTH OF LONE
ROCK...WILL TRACK SOUTHEAST TO THE BARNEVELD AREA BY 1125 PM...AND
WEAKEN. STRONG WINDS ARE NOT EXPECTED WITH THIS STORM. THE REMAINS
OF THIS STORM SHOULD THEN HEAD INTO WESTERN DANE COUNTY.

OTHER THUNDERSTORMS...SOME OF THEM SEVERE...WERE LOCATED NORTHWEST
OF LA CROSSE BACK INTO SOUTHEASTERN MINNESOTA. THESE STORMS WILL
MOVE DOWN THROUGH SOUTHERN WISCONSIN BETWEEN 1 AM AND 7 AM.
DAMAGING WINDS AND LARGE HAIL ARE POSSIBLE WITH THESE STORMS.

KAPELA

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1145 PM CDT WED JUL 19 2006

WIZ046-047-051-052-056>060-062>072-200515-
COLUMBIA-DANE-DODGE-FOND DU LAC-GREEN-GREEN LAKE-IOWA-JEFFERSON-
KENOSHA-LAFAYETTE-MARQUETTE-MILWAUKEE-OZAUKEE-RACINE-ROCK-SAUK-
SHEBOYGAN-WALWORTH-WASHINGTON-WAUKESHA-
1145 PM CDT WED JUL 19 2006

...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR MOST OF
SOUTHERN WISCONSIN UNTIL 7 AM CDT...

SCATTERED STRONG THUNDERSTORMS FROM NORTHWEST AND NORTH OF LA CROSSE
TO THE HILLSBORO AREA OF EASTERN VERNON COUNTY WERE MOVING EAST
SOUTHEAST INTO SOUTHERN WISCONSIN AS OF 1145 PM.

THESE STORMS WILL AFFECT SAUK COUNTY BETWEEN THE MIDNIGHT HOUR AND
1 AM...AND THEN THE REMAINDER OF SOUTH CENTRAL WISCONSIN AFTER 1 AM.
EVENTUALLY SOUTHEAST WISCONSIN WILL FEEL THE AFFECTS OF THESE
STORMS TOWARD 3 AM OR SO.

SHOULD ANY OF THE STORMS BECOME SEVERE...DAMAGING WINDS AND LARGE
HAIL ARE POSSIBLE...ALONG WITH BRIEF HEAVY RAINS THAT CAN LEAVE
PONDING OF WATER ON ROADS AND LOW SPOTS. DANGEROUS LIGHTNING IS
ALSO LIKELY.

OTHERWISE...SCATTERED RAIN SHOWERS OVER DANE COUNTY WILL GRADUALLY
WEAKEN AS THEY MOVE INTO ROCK AND JEFFERSON COUNTIES.

KAPELA

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1248 AM CDT THU JUL 20 2006

WIZ046-047-051-052-056>060-062>072-200700-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
INCLUDING THE CITIES OF...MONTELLO...BERLIN...FOND DU LAC...
SHEBOYGAN...BARABOO...PORTAGE...WISCONSIN DELLS...BEAVER DAM...
WEST BEND...PORT WASHINGTON...DODGEVILLE...MADISON...JEFFERSON...
LAKE MILLS...WAUKESHA...BROOKFIELD...MILWAUKEE...DARLINGTON...
MONROE...JANESVILLE...BELOIT...ELKHORN...LAKE GENEVA...RACINE...
KENOSHA
1248 AM CDT THU JUL 20 2006

...SEVERE THUNDERSTORM WATCH NUMBER 624 REMAINS IN EFFECT UNTIL
7 AM CDT SOUTH AND WEST OF A LINE FROM MILWAUKEE TO HARTFORD TO
RIPON...

A LARGE COMPLEX OF STRONG TO SEVERE THUNDERSTORMS WAS MOVING
RAPIDLY TOWARD THE EAST SOUTHEAST AT 55 MPH. THE STORMS WERE
MOVING ACROSS SOUTHWEST WISCONSIN AND SHOULD MOVE INTO THE MADISON
AREA AT 230 AM AND MILWAUKEE ABOUT 4 AM.

DAMAGING WIND GUSTS TO 70 MPH...HAIL TO QUARTER SIZE...AND A QUICK
2 TO 3 INCHES OF RAIN ARE ALL POSSIBLE AS THE STORMS MOVE THROUGH.
FREQUENT DEADLY CLOUD TO GROUND LIGHTNING IS ALSO ANTICIPATED.

STAY TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE TELEVISION OR
RADIO STATION FOR LATER STATEMENTS AND POSSIBLE WARNINGS.

CRAVEN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
145 AM CDT THU JUL 20 2006

WIZ046-047-051-052-056>060-062>072-200845-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
INCLUDING THE CITIES OF...MONTELLO...BERLIN...FOND DU LAC...
SHEBOYGAN...BARABOO...PORTAGE...WISCONSIN DELLS...BEAVER DAM...
WEST BEND...PORT WASHINGTON...DODGEVILLE...MADISON...JEFFERSON...
LAKE MILLS...WAUKESHA...BROOKFIELD...MILWAUKEE...DARLINGTON...
MONROE...JANESVILLE...BELOIT...ELKHORN...LAKE GENEVA...RACINE...
KENOSHA
145 AM CDT THU JUL 20 2006

...SEVERE THUNDERSTORM WATCH NUMBER 624 REMAINS IN EFFECT UNTIL
7 AM CDT SOUTH AND WEST OF A LINE FROM MILWAUKEE TO HARTFORD TO
RIPON...

A LARGE COMPLEX OF STRONG TO SEVERE THUNDERSTORMS WAS MOVING EAST
SOUTHEAST AT 40 MPH ACROSS SOUTHWEST WISCONSIN AND WAS RAPIDLY
APPROACHING SOUTH CENTRAL WISCONSIN. THE MOST INTENSE STORMS WILL
PRODUCE 70 MPH WIND GUSTS...HAIL TO QUARTER SIZE...AND A QUICK 2
TO 4 INCHES OF RAIN. FREQUENT DEADLY CLOUD TO GROUND LIGHTNING IS
ALSO ANTICIPATED.

AT PRESENT MOTION THE STORMS SHOULD MOVE INTO MADISON AROUND 3 AM
AND MILWAUKEE ABOUT 5 AM THIS MORNING.

STAY TUNED FOR LATER STATEMENTS AND WARNINGS FROM YOUR NATIONAL
WEATHER SERVICE OFFICE IN SULLIVAN WISCONSIN.

CRAVEN