This Month in Climate History: July 1995 Heat Wave

Graph of July 1995 Daily Temperatures

A record-breaking heat wave affected much of the U.S. Midwest in mid-July 1995, and the Chicago area was especially hard hit. From Wednesday, July 12, through Sunday, July 16, 1995, the heat tied or broke a number of temperature records at Chicago’s official reporting station, O’Hare International Airport.

The heat peaked on July 13 when O'Hare Airport had a high of 104°F and a low of 81°F for an average of 93°F, 20 degrees above normal. The heat index—a combination of the temperature and humidity—soared to 119°F at both 1:00 p.m. and 5:00 p.m. CDT. That same day, at Chicago Midway International Airport, on the city’s southwest side, the heat index topped out at 125°F at 2:00 p.m. CDT, with a temperature of 103°F and dew point of 79°F. Even Meigs Field, which sits on a small peninsula jutting into Lake Michigan off the Chicago lakefront, reached 103°F with a heat index of 115°F.

Many people remember this heat wave for the tragic loss of life associated with the event. About 750 people lost their lives, making this the deadliest weather event in Chicago history. The combined and cumulative effects of several days of excessively hot temperatures, high humidity, intense July sunshine, and trapped pollutants took a high toll on the citizens of Chicago. The majority of the victims were elderly and poor city residents who did not have working air conditioners or could not afford to turn them on. Additionally, may people perished when they slept inside with closed windows, some of which were nailed shut for fear of crime. Many important heat-safety lessons used today were learned because of this tragedy.

The extreme conditions also adversely affected infrastructure across Chicago. The Commonwealth Edison power company experienced record demands for electricity on July 12, 13, and 14, 1995. In some areas, due to the high volume of electricity, a loss of power occurred. Additionally, firefighters had to hose down drawbridges over the Chicago River so they would operate and close properly. Several roads buckled from the heat. And, residents opened as many as 500 fire hydrants across the city, causing low water pressure.

To learn more about this historic heat wave, see:

Learn more about heat safety from the National Weather Service’s Beat the Heat Campaign.