Severe Thunderstorm Warning 42, NWS La Crosse, WI

807 
WWUS53 KARX 242310
SVSARX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
610 PM CDT THU MAY 24 2012

WIC019-119-242320-
/O.EXP.KARX.SV.W.0042.000000T0000Z-120524T2315Z/
CLARK WI-TAYLOR WI-
610 PM CDT THU MAY 24 2012

...THE SEVERE THUNDERSTORM WARNING FOR TAYLOR AND NORTHERN CLARK
COUNTIES WILL EXPIRE AT 615 PM CDT...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED BELOW
SEVERE LIMITS. HOWEVER...THE LINE OF STORMS REMAINS STRONG AND COULD
PRODUCE SMALL HAIL AND GUSTY WINDS...IN ADDITION TO LIGHTNING AND
HEAVY RAIN.

A TORNADO WATCH REMAINS IN EFFECT. CONDITIONS REMAIN FAVORABLE FOR
ADDITIONAL SEVERE THUNDERSTORMS TO DEVELOP THAT MAY PRODUCE
TORNADOES.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT THURSDAY EVENING
FOR SOUTHEAST MINNESOTA AND WESTERN WISCONSIN.

LAT...LON 4512 9005 4512 9018 4504 9019 4503 9031
      4488 9031 4474 9059 4465 9091 4509 9093
      4535 9034
TIME...MOT...LOC 2310Z 228DEG 57KT 4543 9034 4529 9014
          4512 9018

$$

04

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
315 PM CDT THU MAY 24 2012

.SHORT TERM...TONIGHT THROUGH SUNDAY
315 PM CDT THU MAY 24 2012

AT 3 PM...A SURFACE LOW WAS LOCATED NEAR DODGE CENTER MINNESOTA. A
COLD FRONT EXTENDED SOUTH NEAR THE INTERSTATE 35 CORRIDOR. MOST
UNSTABLE CAPES HAVE CLIMBED UP TO 1000 J/KG ALONG AND JUST AHEAD
OF THIS FRONT. THERE IS STILL SOME SURFACE BASED CIN /100 TO 300
J/KG / LOCATED ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THIS
IS EXPECTED TO QUICKLY DISSIPATE DURING THE NEXT TWO HOURS AND
STORMS ARE EXPECTED TO BECOME QUICKLY SURFACE BASED. EFFECTIVE
SHEAR IS GREATER THAN 70 KNOTS...THUS EXPECT ANY DISCRETE
THUNDERSTORMS TO QUICKLY BECOME SUPERCELLULAR. THE 0-1 KM SHEAR
IS GREATER THAN 30 KNOTS...0-1 KM SR HELICITY...AND SIGNIFICANT
TORNADO PARAMETERS ARE FAVORABLE FOR THE DEVELOPMENT TORNADOES
OVER SOUTHEAST MINNESOTA THROUGH 22Z AND THEN THIS SHIFTS NORTHEAST
INTO NORTH-CENTRAL WISCONSIN BY 00Z. THIS OCCURS AS THE LOW MOVES
NORTH NORTHEAST THROUGH WEST-CENTRAL AND NORTHEAST WISCONSIN. THE
SEVERE WEATHER THREAT LOOKS LIKE IT WILL SHIFT MAINLY EAST OF THE
AREA BY 01Z. TO THE SOUTH OF THIS TORNADO AREA...THERE WILL BE THE
THREAT OF SUPERCELLS TOO...BUT THE MAIN SEVERE WEATHER THREAT WILL
BE MAINLY DAMAGING STRAIGHT-LINE WINDS.

STRONG GRADIENT WINDS ARE EXPECTED TO CONTINUE ACROSS PARTS OF
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND WESTERN WISCONSIN
THROUGH 7 PM TONIGHT. WINDS WILL GUST UP TO 45 MPH AND SUSTAINED
WINDS WILL RANGE FROM 20 TO 30 MPH.

ON FRIDAY...THE NAM/WRF AND ECMWF GENERATES PRECIPITATION ACROSS
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN.
LOOKING AT THE 925 MB AND 850 MB MOISTURE TRANSPORT AND THE
LOCATION OF THE FRONT...THIS SEEMS TO BE A BIT TOO FAR NORTH. AS A
RESULT...TRENDED THE PRECIPITATION CHANCES MORE TOWARD THE GFS AND
GEM WHICH SUGGESTS THAT THE PRECIPITATION WILL BE MAINLY ACROSS
SOUTHERN IOWA AND NORTHERN ILLINOIS.

ON FRIDAY NIGHT AND SATURDAY...THE WARM FRONT WILL MOVE SLOWLY
NORTH ACROSS IOWA. THIS FRONT WILL THEN PUSH NORTH ACROSS
SOUTHEAST MINNESOTA...AND WEST-CENTRAL...CENTRAL...AND NORTH-
CENTRAL WISCONSIN ON SATURDAY NIGHT. WEAK TO OCCASIONALLY MODERATE
MOISTURE TRANSPORT MOVES NORTHWARD INTO THIS FRONT. THIS WILL
GENERATE SHOWERS AND THUNDERSTORMS. HOWEVER THE MODELS CONTINUE TO
STRUGGLE ON EXACTLY WHERE THE HEAVIEST PRECIPITATION WILL BE
LOCATED WHICH CREATES A BIT OF UNCERTAINTY. WHILE THEIR
UNCERTAINTIES ON PLACEMENT...THEY ARE IN GOOD AGREEMENT THAT THE
WARM CLOUD DEPTHS WILL CLIMB INTO THE 4 TO 4.5 KM RANGE AND THE
PRECIPITABLE WATER VALUES WILL CLIMB UP TO 1.75 INCHES. THIS WILL
MAKE ANY SHOWERS AND THUNDERSTORMS VERY EFFICIENT AT PRODUCING
HEAVY RAIN. THERE WAS SOME CONSIDERATION OF ISSUING AN ESF.
HOWEVER WITH THE DRY SOILS AND UNCERTAINTY OVER THE EXACT
PLACEMENT OF THE HEAVIEST RAIN...DECIDED NOT TO DO IT AT THIS
TIME.

ON SUNDAY...THERE MAY BE SOME LINGERING SHOWERS AND THUNDERSTORMS
ACROSS TAYLOR COUNTY DURING THE MORNING...AND THEN THESE WILL MOVE
NORTH INTO NORTH-CENTRAL WISCONSIN. SOUTH WINDS IN THE 15 TO
25 MPH RANGE WILL BRING VERY WARM AIR NORTHWARD INTO THE REGION.
TEMPERATURES WILL SOAR TO AROUND 90 ALONG AND SOUTH OF THE
INTERSTATE 94 CORRIDOR...AND INTO THE MID AND UPPER 80S ELSEWHERE.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
315 PM CDT THU MAY 24 2012

ON MEMORIAL DAY...THE MODELS CONTINUE TO SHOW THAT A STRONG WAVE
RIDGE WILL FLATTEN THE UPPER LEVEL RIDGE. EVEN THOUGH THIS IS THE
CASE...THERE ARE STILL SOME TIMING DIFFERENCES WITH THE COLD FRONT
MOVING THROUGH THE REGION. THE ECMWF IS ABOUT 6 HOURS AHEAD OF THE
GFS AT MOVING THIS FRONT THROUGH THE FORECAST AREA. THE ECMWF
MOVES IT THROUGH SOUTHWEST AND CENTRAL WISCONSIN DURING THE
MORNING. MEANWHILE THE GFS MOVES IT THROUGH WESTERN
WISCONSIN...AND PARTS OF SOUTHEAST MINNESOTA AND NORTHEAST IOWA
DURING THE AFTERNOON. WHILE THERE ARE TIMING DIFFERENCE...BOTH
MODELS HAVE THE 0-6 KM BULK SHEAR CLIMBING INTO THE 40 TO 50 KNOT
RANGE AND THE ML CAPES INTO THE 1K TO 2K J/KG RANGE. AS A
RESULT...THERE WILL BE THE POTENTIAL FOR SOME SUPERCELL
THUNDERSTORMS TO DEVELOP. THESE THUNDERSTORMS WILL BE CAPABLE OF
PRODUCING DAMAGING WINDS AND LARGE HAIL. THE GFS WOULD SUGGEST
THAT THERE WILL BE THE POTENTIAL OF A FEW TORNADOES. MEANWHILE THE
ECMWF WOULD SUGGEST THAT THE TORNADO POTENTIAL WOULD BE ACROSS
SOUTHEAST IOWA AND NORTHERN ILLINOIS. PRECIPITABLE WATER VALUES
CLIMB INTO THE 1.50 TO 1.75 INCHES AHEAD OF THE FRONT. HOWEVER THE
MOISTURE TRANSPORT IS ONLY MODEST AND THE WARM CLOUD DEPTHS ARE
LESS THAN 3.5 KM...THEREFORE...ONLY EXPECTING SOME BRIEF DOWN
POURS ASSOCIATED WITH THESE STORMS.

FOR THE REMAINDER OF THE TIME PERIOD...THE MODELS SHOW THAT A
SERIES OF SHORT WAVE TROUGHS WILL BE MOVING SOUTHEAST THROUGH THE
FORECAST AREA. AS TYPICAL...THE MODELS ARE STRUGGLING WITH BOTH
THE TIMING AND PLACEMENT OF THESE SYSTEMS. DUE TO THIS...WENT
WITH THE ALL BLEND WHICH HAS 20 TO 40 PERCENT PRECIPITATION
PROBABILITIES. WITH NORTHWEST WINDS ALOFT...TEMPERATURES ARE
EXPECTED TO AVERAGE BELOW NORMAL. HIGH TEMPERATURES WILL BE MAINLY
IN THE LOWER AND MID 60S AND LOW TEMPERATURES MAINLY IN THE 40S.

&&

.AVIATION...THROUGH 18Z FRIDAY
1238 PM CDT THU MAY 24 2012

MAIN AVIATION CONCERNS IS TIMING OF SURFACE COLD FRONT AND
ASSOCIATED SHOWER AND THUNDERSTORMS DEVELOPMENT ALONG THE FRONT THIS
AFTERNOON INTO THIS EVENING. LATEST DETERMINISTIC 24.12Z MODELS SHOW
SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG THE FRONT AROUND 19Z AND
MOVE INTO THE RST TAF SITE APPROXIMATELY OR SHORTLY AFTER 19Z AND 22Z AT
LSE. MODELS INDICATE SOME OF THE THUNDERSTORMS COULD BE SEVERE ALONG
THE FRONT...WITH THE MAIN THREAT BEING STRONG WINDS. OUT AHEAD OF
THE FRONT...THE COMBINATION OF A TIGHTENING PRESSURE GRADIENT AND
MIXING OF WINDS ALOFT DOWN TO THE SURFACE WILL CREATE WINDY
CONDITIONS...ESPECIALLY AT LSE. SUSTAINED WINDS OF 20 TO 25 KNOTS
WITH GUST UP TO 38 KNOTS CAN BE EXPECTED THROUGH THIS EVENING AT
LSE. AFTER FRONTAL PASSAGE LOWER CEILINGS ARE EXPECTED AT BOTH TAF
SITES WITH CEILINGS LOWERING TO MVFR RANGE FOR A SHORT TIME. HIGH
PRESSURE BUILDS INTO THE AREA AFTER 04Z FRIDAY AND SKIES WILL CLEAR
AND WINDS WILL DIMINISH AT BOTH RST AND LSE TAF SITES.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
315 PM CDT THU MAY 24 2012

WI...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR WIZ017-029-033-034-
     041>044-053>055-061.

MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ088-096.

IA...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR IAZ010-011-029-030.

&&

SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DTJ

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LA CROSSE WI
1212 PM CDT THU MAY 24 2012

IAZ010-011-029-030-MNZ088-096-WIZ017-029-033-034-041>044-053>055-061-
251200-
ADAMS-ALLAMAKEE-CLARK-CLAYTON-CRAWFORD-FAYETTE-GRANT-HOUSTON-JACKSON-
JUNEAU-LA CROSSE-MONROE-RICHLAND-TAYLOR-TREMPEALEAU-VERNON-
WINNESHIEK-WINONA-
1212 PM CDT THU MAY 24 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF NORTHEAST IOWA...
FAR SOUTHEAST MINNESOTA...AND SOUTHWEST INTO CENTRAL WISCONSIN.

.DAY ONE...THIS AFTERNOON INTO TONIGHT

SEVERE THUNDERSTORMS ARE EXPECTED LATER THIS AFTERNOON AND INTO THE
EVENING AS A STRONG COLD FRONT SWEEPS ACROSS THE AREA. DAMAGING
THUNDERSTORM WINDS AND BRIEF HEAVY DOWNPOURS REMAIN THE MAIN
THREATS...THOUGH A TORNADO OR TWO COULD ALSO OCCUR. THE PEAK TIMING
FOR THUNDERSTORMS IS FROM 4 TO 9 PM WITH THE STORMS MOVING RAPIDLY
FROM WEST TO EAST ACROSS THE REGION.

A WIND ADVISORY IS ALSO IN EFFECT FOR THIS AFTERNOON. STRONG AND
GUSTY SOUTH WINDS WITH SUSTAINED SPEEDS OF 25 TO 35 MPH AND GUSTS UP
TO 45 MPH ARE POSSIBLE. THESE STRONG WINDS WILL BE MORE LIKELY OVER
THE HIGHER TERRAIN AND RIDGE TOP AREAS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

PERIODIC CHANCES OF THUNDERSTORMS CONTINUE ACROSS MUCH OF THE AREA
FRIDAY NIGHT THROUGH MONDAY AND AGAIN ON WEDNESDAY. THERE IS THE
POTENTIAL FOR ONE OR MORE PERIODS OF SEVERE WEATHER...POSSIBLY ON
SATURDAY AND SUNDAY NIGHT INTO MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED BETWEEN 4 AND 9 PM LATER THIS
AFTERNOON AND EARLY THIS EVENING. DUE TO EXPECTED RAPID STORM
MOVEMENT...HIGHER LEAD TIME FOR ACTIVATION OR SPOTTER PLACEMENT
MIGHT BE MORE DIFFICULT.

.EMERGENCY MANAGEMENT COORDINATION...

NO WEBINAR OR BRIEFING IS PLANNED AT THIS TIME. A WEBINAR WAS HELD
AT 11 AM THURSDAY.

IAZ008-009-018-019-MNZ079-086-087-094-095-WIZ032-251200-
BUFFALO-CHICKASAW-DODGE-FILLMORE-FLOYD-HOWARD-MITCHELL-MOWER-OLMSTED-
WABASHA-
1212 PM CDT THU MAY 24 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
MINNESOTA...NORTHEAST IOWA...AND FAR WESTERN WISCONSIN.

.DAY ONE...THIS AFTERNOON INTO TONIGHT

SEVERE THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AS A STRONG COLD
FRONT SWEEPS ACROSS THE AREA. DAMAGING THUNDERSTORM WINDS AND BRIEF
HEAVY DOWNPOURS ARE THE MAIN THREATS...THOUGH A TORNADO OR TWO MAY
ALSO OCCUR. STORMS SHOULD BE EAST OF THE AREA BY EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

PERIODIC CHANCES OF THUNDERSTORMS CONTINUE ACROSS MUCH OF THE AREA
FRIDAY NIGHT THROUGH MONDAY AND AGAIN ON WEDNESDAY. THERE IS THE
POTENTIAL FOR ONE OR MORE PERIODS OF SEVERE WEATHER DURING THIS TIME
FRAME...POSSIBLY SATURDAY AND AGAIN SUNDAY NIGHT INTO MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON...BEFORE 5PM.
DUE TO EXPECTED RAPID STORM MOVEMENT...HIGHER LEAD TIME FOR
ACTIVATION OR SPOTTER PLACEMENT MIGHT BE MORE DIFFICULT.

.EMERGENCY MANAGEMENT COORDINATION...

NO WEBINAR OR BRIEFING IS PLANNED AT THIS TIME. A WEBINAR WAS HELD
AT 11 AM THURSDAY.

SHEA

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
510 PM CDT THU MAY 24 2012

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

0500 PM     TSTM WND DMG     GOODVIEW                44.07N 91.71W
05/24/2012                   WINONA             MN   911 CALL CENTER

            TREES DOWN IN GOODVIEW. POWER OUTAGE.

&&

DAVIS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
520 PM CDT THU MAY 24 2012

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

0510 PM     HAIL             2 WSW GALESVILLE        44.07N 91.39W
05/24/2012  E0.75 INCH       TREMPEALEAU        WI   NWS EMPLOYEE

&&

ADAMS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
522 PM CDT THU MAY 24 2012

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

0517 PM     TSTM WND GST     3 N OELWEIN             42.72N 91.91W
05/24/2012  E50 MPH          FAYETTE            IA   TRAINED SPOTTER

&&

ADAMS

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
527 PM CDT THU MAY 24 2012

IAZ010-011-029-030-WIZ042-053-054-242330-
ALLAMAKEE-CLAYTON-CRAWFORD-FAYETTE-MONROE-VERNON-WINNESHIEK-
527 PM CDT THU MAY 24 2012

...STRONG THUNDERSTORMS EXPECTED IN ALLAMAKEE...CLAYTON...CRAWFORD...
FAYETTE...MONROE...VERNON AND WINNESHIEK COUNTIES...

AT 524 PM...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS FROM NEAR
CATALIA TO OELWEIN...MOVING NORTHEAST AT 45 MPH.

WIND GUSTS UP TO 55 MPH AND SMALL HAIL MAY ACCOMPANY THESE STRONG
THUNDERSTORMS. PEA SIZED HAIL WAS RECENTLY REPORTED IN FRANKVILLE.

LOCATIONS THAT MAY BE AFFECTED INCLUDE...
ARLINGTON...LANSING...MONONA...FARMERSBURG AND HARPERS FERRY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM THURSDAY EVENING FOR
SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. A SEVERE THUNDERSTORM
WATCH ALSO REMAINS IN EFFECT UNTIL 1000 PM THURSDAY EVENING FOR
NORTHEAST IOWA AND SOUTHWEST WISCONSIN.

04

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
528 PM CDT THU MAY 24 2012

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

0515 PM     HAIL             1 N HANNIBAL            45.26N 90.78W
05/24/2012  E1.00 INCH       TAYLOR             WI   TRAINED SPOTTER

            ALSO ESTIMATED WIND GUST OF 60 MPH

&&

TMS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LA CROSSE WI
532 PM CDT THU MAY 24 2012

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

0518 PM     TSTM WND DMG     FRANKVILLE              43.18N 91.64W
05/24/2012                   WINNESHIEK         IA   TRAINED SPOTTER

            A NUMBER OF TREES DOWN IN FRANKVILLE

&&

DAVIS