739 Dead in Five Days: Inside The Deadly Chicago Heat Wave of 1995

For five days in July 1995, Chicago experienced one of the deadliest weather disasters in American history — not a hurricane, not a tornado, but a slow, suffocating heat wave that killed 739 people.

The Numbers Behind the Heat

The crisis peaked between July 12 and July 16, 1995, when a massive high-pressure system parked itself over the Midwest and refused to move. On July 13, the temperature at Chicago Midway International Airport hit 106°F — the second-hottest reading ever recorded there, behind only the 110°F set in 1934. What made this heat wave especially dangerous wasn't just the daytime highs. Overnight lows stayed in the upper 70s and low 80s, giving the city's residents no relief and no chance to cool down before the next scorching day began.

Humidity turned dangerous heat into lethal heat. Unlike the dry heat waves of the 1930s, 1950s, and 1970s, this one carried moisture pulled north from Iowa. Dew points across the region climbed past 80°F, with one station in Appleton, Wisconsin recording a heat index of 153°F, a probable record for the Western Hemisphere. Across Iowa and southern Wisconsin, heat indices topped 130°F on multiple days. Wet-bulb temperatures in the Chicago area reached 85°F, edging toward levels that can overwhelm the human body's ability to cool itself through sweat.

Chicago's daily highs and lows that week tell the story: