Here are Chicago’s hottest days — with temperatures of 100 degrees or higher — on record

Temperatures at or above the century mark are a rarity in Chicago.

Yet, 100 degrees was recorded on Thursday for the first time in more than a decade at O’Hare International Airport, the city’s official recording site.

That makes just 66 days, when looking back through more than 136 years of data kept by the National Weather Service, that have logged triple-digit temperatures.

The first was observed on July 16, 1887. When the Tribune reported on “how fashionable people solve the hot weather problem,” suggestions included reading a book indoors, going on a canoe excursion or leaving town for a cooler locale.

The highest temperature on record in Chicago was 105 degrees logged on July 24, 1934, but unofficial results have been even more extreme. Documented highs of 109 degrees during the Dust Bowl in 1934 and 106 during an oppressive heat wave in 1995 were set at other sites in the city.

On July 13, 1995, Chicago’s high temperature for the day reached 104 degrees during a notorious heat wave that killed more than 700 area residents. That one sweltering week would change the way Chicago responds to and prepares for all emergencies.

Here’s a look back at the hottest temperatures on record in Chicago and how the Tribune reported them.

Hottest day in Chicago history: 105 degrees (July 24, 1934)

What the Tribune reported

“There were fifteen deaths in Chicago which were ascribed definitely to heat prostration. In addition to these there were more than thirty deaths from heart disease and other ailments in which the heat was regarded as a contributing factor. ...

“The 12th prostration victim was Karol R. Bielawski, 43 years old, 1629 North Mobile avenue, who dropped dead over the wheel of his truck while driving in Ogden avenue near Warren boulevard. ...

“Although temperatures throughout the middle west and the east were extremely high Monday and yesterday, pilots on the transcontinental air lines reported comfortable weather only a few thousand feet above the ground. One pilot, flying a TWA Douglas air liner to Pittsburgh from Chicago, found the temperature 32 degrees at 15,000 feet and was forced to turn on heat in the cabin for the comfort of shivering passengers.” Read more.

Just two days earlier, John Dillinger — dubbed America’s first Public Enemy No. 1 by U.S. Attorney General Homer S. Cummings — was gunned down by federal agents outside the air conditioned Biograph Theatre.

104 degrees (June 20, 1953)

What the Tribune reported

“Of the estimated 350,000 persons who sought relief at beaches and pools, five drowned, scores suffered heat prostration, and thousands took home second-degree sunburns. Another 150,000 tried to duck the heat by seeking shade trees in forest preserves and parks.

“More than 300 motorists were temporarily stranded, the Chicago Motor club reported, when vapor locks developed in carburetors. They had to wait until engines cooled off. Some Chicago transit authority buses were slowed because of overheating, but service was maintained.

“The heat softened blacktop roads in many parts of the Chicago area. Pavement buckled in two places in Lake county — route 173, near Channel Lake, and route 134, near Big Hollow. ...

“It was also the hottest spring day in Chicago weather history, because summer does not begin until noon today, and the warmest day of this year, exceeding Friday’s 101.8 degrees.

“There were only two cities in the country which registered higher temperatures than Chicago. These were Abilene, Tex., and Oklahoma City, Okla., with 105 degrees each. Fort Worth, Tex., and Yuma, Ariz., equaled Chicago’s mark of 104. ...

“In some neighborhoods, adults joined children in opening fire hydrants to get momentary relief. ...

“Police also were busy on south side beaches, taking care of the 75,000 persons there and ticketing 150 illegally parked cars that blocked entrances and exits.

“Unusually small crowds attended Lincoln Park and Brookfield zoos. Directors Robert Bean of Brookfield said the animals appeared to be comfortable despite the heat. ‘They are more judicious than humans, and never seek second degree burns on beaches,’ he said.”

Other 104-degree days

  • June 20, 1988: “On the first day of summer Monday, Chicago-area residents experienced two weather milestones. The thermometer at O’Hare International Airport read 104 degrees at 4:26 p.m., the second-hottest temperature ever recorded in Chicago. And it rained for the first time in nearly a month.”

  • July 13, 1995: “From the Department of Scant Consolation: Only about one two-billionths of the sun’s heat and light reaches the Earth. The rest of our star’s blazing energy is lost in space or absorbed by the other planets in the solar system. That’s true day in and day out. But on a day like Thursday, it seemed as though the sun was focusing all of its searing heat on the Chicago area.”

103 degrees (July 5-6, 2012)

What the Tribune reported

“Some were elderly. Others lived alone. All had underlying health problems.

“While many Chicagoans were able to escape the third day of triple-digit temperatures Friday — retreating to air-conditioned homes or cooling centers — authorities said that over the last few days, at least six people have succumbed to the stifling heat.

“‘There will always be some people who are very hard to reach,’ Chicago Fire Department spokesman Larry Langford said. ‘It could be a person who is down on their luck, it could be a person who has good resources but no one to monitor them, it could be a person who doesn’t want to leave their home.’”

Other 103-degree days

  • July 21, 1901: “Yesterday was the hottest day Chicago ever has known. The thermometer made a pole-vault for the record, reached it at 2 o’clock, slipped back to get a fresh start, and made a flying leap that cleared the record by a full degree. Then, to cap the climax, the mercury registered the hottest evening the Weather bureau has ever had to record in Chicago.

  • July 1, 1956: “It was the 13th day this year that the temperature has exceeded 90. The number of days with 90 or higher temperatures is ahead of last year when the all-time record of 46 such days in one year was set. The 13th 90 degree or higher day did not come until July 19 last year.”

  • June 25, 1988: “Chicago’s official high temperature was a record (for June 25) 103 degrees at O’Hare International Airport at 3 p.m., and it was 2 degrees higher at Lake Michigan. By midnight, however, the temperature had dropped to a cool 66 and was expected to fall even more before dawn.”

Sources: Tribune research, reporting and archives; National Weather Service

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krumore@chicagotribune.com

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