Heat in Wisconsin

Events

900

Deaths

41

Injuries

326

Damage

None recorded

• Heat in Wisconsin, July 29 to 31, 19998 deaths · 20 eventsThe most intense heat wave since the killer heat wave of July 13-14, 1995, struck southcentral and southeast Wisconsin at the end of July, 1999.
• Heat in Wisconsin, July 2 to 7, 20125 deaths · 50 injured · 13 eventsFive people died from the effects of a long duration heatwave that gripped western Wisconsin from July 2nd through July 7th. Two of the deaths occurred in La Crosse County with one each in Juneau, Richland and Vernon Counties.
• Heat in Wisconsin, August 6 to 9, 20014 deaths · 20 eventsThis excessive heat episode was the third, and longest, of the 2001 summer in south-central and southeast Wisconsin. Daytime heat indices reached 105 to 110, and stayed above 80 at night. Maximum air temperatures were in the lower to mid 90s, while dewpoints were in the mid 70s.
• Heat in Wisconsin, June 29, 199670 injured · 1 eventA minimal heat wave produced air temperatures of 95 degrees and dewpoints in the lower to mid 70s, and heat indices of 105 to 110 for one day. The lowest air temperature in Milwaukee on the 29th was 74. A large crowd attended the Summerfest event on Milwaukee's lakefront.
• Heat in Wisconsin, July 23 to 31, 19993 deaths · 22 eventsOver one week of hot and very humid conditions across northeast Wisconsin resulted in numerous heat related illnesses and 3 deaths due to excessive heat.
• Heat in Wisconsin, July 20 to 21, 201160 injured · 4 eventsA dome of hot and humid air over the southern and central Plains built northward into the Upper Midwest and affected different parts of Wisconsin on different days during the period of July 17th through July 21st. Heat index values reached 100 to 110 in this heat event.
• Heat in Wisconsin, June 16 to 20, 20123 deaths · 2 eventsGusty southwest winds of 20 to 35 mph brought a hot air-mass into southern Wisconsin, with maximum air temperatures reaching the lower to middle 90s, and daytime maximum heat index values of 95 or 96, beginning the afternoon of June 16th and lasting through the afternoon hours…
• Excessive Heat and Heat in Wisconsin, June 14 to 15, 20222 deaths · 20 eventsPersistent southwest winds brought hot and humid conditions to southern WI. Heat index values well over 100 degrees occurred. Cooling centers were opened in some communities. Two heat related fatalities occurred in Milwaukee.
• Heat in Wisconsin, July 30 to 31, 200640 injured · 18 eventsA period of very hot and humid weather began on the evening of July 30th and continued into August 2nd. Overnight temperatures only fell to 70 to 75 on the 30th, and soared into the 95 to 100 degree range during the afternoon of July 31st.
• Heat in Wisconsin, August 1 to 2, 20062 deaths · 18 eventsThis heat event for August 1st-2nd is a continuation of the same heat event that started on the evening of July 30th.
• Heat in Wisconsin, July 31, 20012 deaths · 13 eventsTemperatures climbed into the middle to upper 90s, with La Crosse (La Crosse County) even reaching 100. The excessive heat combined with high humidity pushed heat indices dangerously high, with values of 105 to 115.
• Excessive Heat and Heat in Wisconsin, July 19 to 20, 201939 injured · 20 eventsPersistent southwest winds and the passage of a warm front brought a heat wave to southern WI. The Milwaukee and Madison areas did experience an influx of emergency room visits due to heat exhaustion and/or heat stroke.
• Heat in Wisconsin, July 21 to 22, 20012 deaths · 9 eventsThe first, significant round of excessive heat for the summer of 2001 affected parts of south-central and southeast Wisconsin. Medical examiner reports indicated that two people died from heat exposure in Milwaukee County - a female (52), and a male (34).
• Heat in Wisconsin, July 21 to 24, 201629 injured · 20 eventsHot and humid conditions became established across southern WI for several days. Maximum heat index values reach 95 degrees or warmer for the majority of this period. The WI Department of Health Services designated hundreds of cooling centers across WI.
• Heat in Wisconsin, April 15 to 18, 20021 death · 20 eventsAn out-of-season heat wave affected south-central and southeast Wisconsin thanks to a very warm, moist airmass which settled in for the 4-day period of April 15-18.
• Heat in Wisconsin, July 15 to 17, 20121 death · 20 eventsAnother round of excessive heat hit southern Wisconsin mid-month, with high temperatures in the mid to upper 90s and dew points in the mid to upper 60s beginning on July 15th and lasting through July 17th.
• Heat in Wisconsin, July 28 to 30, 19991 death · 13 eventsOppressive heat and humidity affected the area once again with highs in the middle 90s to 100. La Crosse (La Crosse County) established new record highs when the temperature reached 98 and 100 on the 29th and 30th respectively. Heat indices both days topped out around 120.
• Heat in Wisconsin, June 25, 199821 injured · 1 eventHigh levels of heat and humidity over Milwaukee County, amplified by the "urban heat-island" effect, resulted in 21 people being treated at area hospitals for heat-related injuries/exhaustion.
• Heat in Wisconsin, June 22 to 25, 20021 death · 9 eventsA long-duration, early-season. heat wave affected Milwaukee and Racine counties, resulting in a directly-related death, and an indirectly-related death. This heat wave didn't meet official heat-wave criteria, but the duration and timing was sufficient to adversely affect humans.
• Heat in Wisconsin, July 16 to 17, 20121 death · 9 eventsHot temperatures returned to central and east central Wisconsin during the middle of the month. High temperatures were mainly in the 90s but heat index values topped out at 95 to 105. A 71 year old man in poor health became ill from the heat and eventually died on July 18.
• Heat in Wisconsin, June 20, 20021 death · 5 eventsA brief, one day heat wave affected parts of southeast Wisconsin, resulting in the death of a 38-year-old male in the city of Milwaukee. After several days with maximum temperatrures in the 50s, 60's and 70's, the heat on June 20th was sudden enough to affect humans.
• Heat in Wisconsin, July 16, 19971 death · 2 eventsHot, muggy air settled over southeast Wisconsin. A new daily maximum temperature of 98 was set in Sheboygan, breaking the old record of 97 set back in 1931.
• Heat in Wisconsin, July 31, 20011 death · 1 eventAlthough the temperature remained below 90 degrees and the heat index never reached 100 degrees on July 31st, a heat related death was reported in the city of Manitowoc. The woman was pronounced dead on August 4th.
• Heat in Wisconsin, July 20, 20011 death · 1 eventA man died after fishing on Lake Stanley (in Stanley) during warm and humid weather. According to the cooperative observer in Stanley, the maximum temperature on the 20th was 85.
• Heat in Wisconsin, July 16, 20131 death · 1 eventOne person passed away from heat related causes near Osseo (Trempealeau County) during a heat wave in the middle of July. The victim apparently fell outside a house on a day when full sunshine was occurring.

Heat everywhereEvery kind of event in Wisconsin

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.