A strong surface pressure gradient around a departing deep low pressure system moving from central Lake Superior to southwest Quebec, Canada produced westerly wind gusts between 39 and 43 knots (45 and 50 mph) during the afternoon hours, mainly over Southeast Wisconsin. There were scattered reports of downed power lines due to broken tree branches falling on wires.
Every event with a place to put it; 9 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MKX wrote it up.
A strong surface pressure gradient around a departing deep low pressure system moving from central Lake Superior to southwest Quebec, Canada produced westerly wind gusts between 39 and 43 knots (45 and 50 mph) during the afternoon hours, mainly over Southeast Wisconsin. There were scattered reports of downed power lines due to broken tree branches falling on wires.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Milwaukee, WI wrote its last area forecast discussion before the first event at Sep 24, 2:30 AM CST, 8 hours 30 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 330 AM CDT FRI SEP 24 2010 FORECAST FOCUS ON ENDING RAIN AND WINDS TODAY...COOLER AND MORE SEASONABLE TEMPERATURES THROUGH THE WEEKEND. .SHORT TERM...TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH. COLD FRONT TO SHIFT EAST THROUGH THE AREA EARLY THIS MORNING...EXITING THE EAST BY 13Z AT THE LATEST. MOST OF THE RAIN ASSOCIATED WITH THE FRONT WILL MOVE EAST ALONG WITH IT. THERE MAY BE ISOLATED SHOWERS ACROSS THE NORTHERN COUNTIES DURING THE MORNING...WITH VORTICITY MAXIMUM PUSHING THROUGH THAT AREA. HOWEVER...MOST OF THE AREA SHOULD REMAIN DRY. MAIN ISSUE IS WITH EXPECTED WIND GUSTS ACROSS THE AREA TODAY. STRONG PRESSURE GRADIENT REMAINS ACROSS THE AREA WITH THE DEEP LOW MOVING AWAY FROM THE AREA. AREA FORECAST SOUNDINGS SUGGEST WINDS IN THE MID TO UPPER 30 KNOT RANGE AT 1000 FEET ABOVE GROUND LEVEL MIXING DOWN...CLOSE TO WIND ADVISORY CRITERIA. FEEL THAT GUSTS WILL BE BORDERLINE FOR AN ADVISORY...SO WILL HOLD OFF ON ONE FOR NOW. DAY SHIFT WILL HAVE TO MONITOR. WOULD NOT BE SURPRISED TO SEE A FEW SITES REACH CRITERIA. WINDS TO RELAX TONIGHT AS HIGH PRESSURE BUILDS INTO THE AREA. SKIES SHOULD ALSO GRADUALLY CLEAR OUT. PATCHY FOG POSSIBLE IN LOW LYING AREAS LATE TONIGHT. COLDER TEMPERATURES EXPECTED TO PUSH INTO THE REGION WITH COLD AIR ADVECTION TODAY...LINGERING THROUGH THE UPCOMING WEEKEND. .LONG TERM...SATURDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM. PASSING SHORTWAVE TROUGH MOVING TO THE SOUTHEAST WILL BRING A GLANCING BLOW OF SHOWERS TO THE AREA SATURDAY AFTERNOON AND EVENING. OTHERWISE...THE REST OF THIS PERIOD SHOULD REMAIN MAINLY DRY. COOL TEMPERATURES EXPECTED UNTIL EARLY NEXT WEEK. && .AVIATION...WILL MONITOR NEED TO KEEP LOW-LEVEL WIND SHEAR IN FORECAST AT EASTERN SITES FOR A BRIEF PERIOD BEFORE WINDS SLACKEN AS SURFACE/850MB TROUGHS MOVE THROUGH. WINDS WILL PICK RIGHT BACK UP BY 18Z AS POCKET OF 50KT 850MB WINDS...CURRENTLY SHOWING UP ON KABR AND KFSD VAD WINDS...CROSS REGION. CLOSE CALL ON LLWS FOR THIS AFTERNOON...BUT APPEARS STRONGER WINDS WILL BE NORTH OF TAF SITES SO WILL LEAVE OUT. WILL ALSO TAKE OUT PRECIPITATION AFTER SURFACE FRONTAL PASSAGE...AS MODELS KEEP WRAP AROUND MOISTURE WITH 500 MB LOW NORTH OF TAF SITES. EXTENSIVE AREA OF MVFR CEILINGS WITH COLD AIR ADVECTION UNDER CYCLONIC FLOW SUPPORT CURRENT FORECAST TREND AND WILL BE KEPT. && .MARINE...GALE WARNING TIMING WILL BE KEPT FOR NOW...THOUGH LATER SHIFTS WILL HAVE TO LOOK AT EXTENDING IF 1000 FT WINDS REMAIN ABOVE 35 KTS. MODEL SOUNDINGS ALL SHOW 1000 FT WINDS EASING AROUND 00Z...BUT NOT CONSISTENTLY ALONG THE SHORE...ESPECIALLY OVER THE NORTHERN ZONES. GALE WARNING WILL HAVE TO BE FOLLOWED WITH A SMALL CRAFT ADVISORY...WITH FREQUENT GUST POTENTIAL LINGERING INTO SATURDAY MORNING. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...GALE WARNING IN EFFECT UNTIL 7 PM CDT FRIDAY FOR LMZ643>646. && SHORT/LONG TERM...08/WOOD AVIATION/MARINE...09/REM UPDATED TO ADD AVIATION AND MARINE SECTIONS AND EDIT LONG TERM SECTION.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 433 AM CDT FRI SEP 24 2010 WIZ046-047-051-052-056>060-062>072-250945- MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE- WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE- LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA- 433 AM CDT FRI SEP 24 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN. .DAY ONE...TODAY AND TONIGHT GUSTY WEST WINDS WILL APPROACH WIND ADVISORY CRITERIA TODAY BEHIND A COLD FRONT AS LOW PRESSURE MOVES AWAY TO THE EAST. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. LMZ643>646-250945- 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- 433 AM CDT FRI SEP 24 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT A GALE WARNING IS IN EFFECT THROUGH THIS AFTERNOON FOR GUSTY WEST WINDS THAT WILL BUILD HIGH WAVES. SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE AFTER WINDS FALL BELOW GALE CRITERIA TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY SMALL CRAFT ADVISORY CRITERIA WILL LINGER INTO EARLY SATURDAY MORNING FOR GUSTY NORTHWEST WINDS AND HIGH WAVES. REM WWW.WEATHER.GOV/MKX
The national radar mosaic for the moment the first event began.
9 strong wind. Local standard time, as filed.
The ASOS at the Sheboygan Airport recorded a 41 knot (47 mph) wind gust at 1117 am LST.
The AWOS at Crites Field in Waukesha recorded a 40 knot (46 mph) wind gust at 1245 pm LST.
The ASOS at Mitchell International Airport in Milwaukee recorded a 41 knot (47 mph) wind gust at 1101 am LST.
The ASOS at the Kenosha County Airport measured a wind gust of 45 mph (39 knots) at 215 pm LST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2010Every state in 2010This day in weather historyWarnings in Wisconsin, September 2010
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 262426, 262428, 262429, 262430, 262431, 262435, 262442, 262444, 262446.