A ridge of high pressure settled over the Midwest. A very warm air mass with light winds and plenty of sunshine allowed temperatures to warm into the low to mid 90s away from Lake Michigan.
Every event with a place to put it; 3 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 ridge of high pressure settled over the Midwest. A very warm air mass with light winds and plenty of sunshine allowed temperatures to warm into the low to mid 90s away from Lake Michigan. Dewpoint temperatures were in the low 70s. Heat index values reached 100 to 101 degrees inland from Lake Michigan by late afternoon.
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 Jun 22, 3:05 AM CST, 10 hours 55 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 405 AM CDT MON JUN 22 2009 .DISCUSSION...FORECAST FOCUS IS ON PRECIP TRENDS TODAY...HEAT FOR TUESDAY/WEDNESDAY WITH BUILDING UPPER RIDGE...THEN COLLAPSE OF RIDGE WITH SHORTWAVE/FROPA FOR LATER WEDNESDAY INTO WEDNESDAY NIGHT. TODAY- IMPRESSIVE SURFACE/850 MILLIBAR DEW POINT GRADIENT ALIGNED IN A NW/SE FASHION FROM CENTRAL MN TO NORTHERN IL. DRIER DEW POINTS KNIFING INTO EASTERN WI WITH DEW POINTS IN THE UPPER 50S WITH LOW 70 DEW POINTS IN NE IA. WATER VAPOR SHOWS PRONOUNCED DRYING WITH CONVECTION FIRING ON THE LEADING EDGE OF THE DRYING. LOW LEVEL JET FAVORABLE TO OUR WEST AND DOES NOT BECOME A FACTOR FOR US HERE. WEAK WAVES AT 500 MILLIBARS DO AFFECT US...THE MAIN WAVE COMES THROUGH BY 18Z BUT BOTH GFS AND NAM SHOW A WEAKER VORT COMING THROUGH THIS AFTERNOON WITH SOME LINGERING 1000-850 CONVERGENCE AT PLAY AS WELL. GFS QUITE AGGRESSIVE WITH QPF AFTER 18Z. SO LINGERING THE POPS INTO THE AFTERNOON SEEMS REASONABLE. TONIGHT- UPPER RIDGE BUILDS WITH 850/SURFACE RIDGE AXES BECOMING DOMINANT THOUGH 850 AXIS STILL TO OUR WEST WITH SOME NORTHERLY COMPONENT AT PLAY. LIGHT WINDS IN THE LOWEST LAYERS SO WITH EXPECTRED CLEAR SKIES...THE PATCHY FOG IDEA STILL LOOKS GOOD. TUESDAY- THE HEAT IS ON. 850 TEMPS INTO THE LOW 20S...WITH 925 TEMPS AVERAGING 25-27C. THIS TRANSLATE TO NON-LAKE INFLUENCED AREAS REACHING 90 TO 95...WITH 80S LAKESIDE. GETTING INTO TUESDAY NIGHT...PREFER THE DRY LOOK OF THE NAM/ECMWF/CANADIAN AS THE GFS GOES BONKERS WITH CONTAMINATED VORT CENTERS. WEDNESDAY AND WEDNESDAY NIGHT- THE UPPER RIDGE GRADUALLY FLATTENS WITH DECENT H2-H3 JET CORE TRAVERSING AROUND A STRONG CANADIAN TROUGH. THE JET CORE RESULTS IN AN IMRESSIVE UPPER DIVERGENCE FIELD ACROSS THE CWA...BOTH NAM AND GFS SHOW THIS AT 00Z THURSDAY. ML CAPE VALUES RANGE FROM 2-4K J/KG THOUGH BEST CAPE OCCURS WITH BEST 0-6KM AND 0-1 SHEAR FURTHER NORTH. NOT AN OVERLY IMPRESSIVE SURFACE/850 FRONT BUT NEVERTHELESS STILL ENUF INSTAB/MOIST TO WORK WITH COMBINED WITH INCREASING FAVORABLE UPPER JET DYNAMICS. THURSDAY AND FRIDAY- HIGH PRESSURE SHOULD DOMINATE IN WAKE OF FRONT AND SHORTWAVE. NEXT CHANCE FOR STORMS ARRIVES FOR FRIDAY NIGHT AND BASED ON COMBO OF ECMWF/GFS QPF PROGS...WILL RANGE POPS FROM VERY LOW/DRY IN THE SE TO CHANCY IN THE NW CWA. && .AVIATION...BAND OF SHOWERS AND SCATTERED THUNDERSTORMS WITH MVFR CIGS AND VSBYS. FEW IFR CIGS ALSO EXPECTED. EXPECT SHOWERS AND THUNDERSTORMS TO END FROM WEST TO EAST THIS MORNING AS WEAK MID LEVEL TROUGH PUSHES NORTHEAST. SHOWERS/THUNDERSTORMS SHOULD WEAKEN AS THEY PUSH INTO MORE STABLE AIRMASS. SOME INSTABILITY THIS AFTERNOON WITH ONLY WEAK CAP. AS A RESULT ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE...BUT FORCING IS LACKING. && .MARINE...PATCHY FOG EXPECTED OVER THE LAKE TODAY DUE TO WEAK SOUTHEAST FLOW AND HIGH DEWPOINTS OVER THE COLDER WATERS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && SHORT/LONG TERM...COLLAR AVIATION/MARINE...HENTZ
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 111 PM CDT MON JUN 22 2009 WIZ046-047-051-052-056>060-062>072-230900- MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE- WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE- LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA- 111 PM CDT MON JUN 22 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN. .DAY ONE...TODAY AND TONIGHT THERE IS A CHANCE OF THUNDERSTORMS OVER PORTIONS OF SOUTH CENTRAL AND SOUTHEAST WISCONSIN TODAY. HEAT INDEX VALUES WILL RISE TO AROUND 95 OVER PORTIONS OF SOUTH CENTRAL WISCONSIN THIS AFTERNOON. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY HEAT INDEX VALUES WILL RISE TO NEAR 100 OVER SOUTH CENTRAL WISCONSIN AND TO NEAR 95 OVER PORTIONS OF SOUTHEAST WISCONSIN TUESDAY AFTERNOON. HEAT INDEX VALUES WEDNESDAY AFTERNOON SHOULD REACH FROM 97 TO 102 ACROSS MOST OF SOUTH CENTRAL AND SOUTHEAST WISCONSIN. THERE IS A CHANCE OF THUNDERSTORMS WEDNESDAY THROUGH WEDNESDAY NIGHT...AND AGAIN FRIDAY NIGHT THROUGH SATURDAY EVENING. THE WISCONSIN DEPARTMENT OF NATURAL RESOURCES HAS ISSUED AN AIR QUALITY WATCH FOR SOUTHEAST WISCONSIN ON TUESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT. LMZ643>646-230900- 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- 111 PM CDT MON JUN 22 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT AREAS OF FOG ARE POSSIBLE TODAY AND TONIGHT. THERE IS A CHANCE OF THUNDERSTORMS TODAY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THERE IS A CHANCE OF THUNDERSTORMS WEDNESDAY THROUGH WEDNESDAY NIGHT...AND AGAIN FRIDAY NIGHT THROUGH SATURDAY EVENING. BORGHOFF WWW.WEATHER.GOV/MKX
The national radar mosaic for the moment the first event began.
3 heat. Local standard time, as filed.
At 2PM CST, Monroe Airport recorded a max temperature of 90 with a dewpoint of 75, resulting in a heat index of 100.
Pardeville RAWS recorded a maximum heat index of 100 at 4 PM CST.
Dodgeville RAWS recorded a maximum heat index of 101 at 2 PM CST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2009Every state in 2009This day in weather historyWarnings in Wisconsin, June 2009
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: 177184, 177223, 177234.