The thermometer soared into the high 90s. An excessive heat warning runs until 4 a.m. Friday.
"We had a high today of 99, the warmest day in almost five years," said ABC7 meteorologist Jerry Taft.
An open hydrant was one way to cool off, but some Pilsen residents weren't happy about the method.
"Water has been going over the sidewalk and down into the garden area. So that's a problem just in terms of just flooding," said Megha Patel, Pilsen resident.
With hundreds of hydrants being opened across the city, the Chicago Fire Department says it has run into water pressure problems. Capping the hydrants can take precious time during an emergency.
"They're not using the proper equipment, thus causing us problems if we come upon them to shut them down to use them. We can't because obviously they're damaged," said Dist. Chief Tom Kennedy, Chicago Fire Department.
With the city baking in stifling heat, the Office of Emergency Management and Communications has beefed up paramedic staffing at fire houses across the city. Manpower this week is at its highest level since the February blizzard.
"Hour by hour we're evaluating what kind of runs we're getting, the status of the runs, and we can move companies around," said Chief Robert Ambos, Chicago Fire Department.
At one point OEMC was receiving 10 to 12 calls per hour.
In extreme heat, the body, even at rest, can lose a quart of fluid an hour.
"Once you stop sweating, now you really have to get to medical care. In the very least get into a cold environment and drink a lot of water," said Dr. Jordan Moskoff, John H. Stroger Hospital.
Young children are especially vulnerable because kids' bodies can take longer to adjust to extreme heat.
"Cooling off is key. Even air conditioning for a few hours is helpful," said Dr. Karen Sheehan, Children's Memorial Hospital.
With the on-field temperature at Wrigley Field reading 120 degrees at game time Wednesday, stadium staff handed out free water and portable misters.
"Unless you had your phone or your camera out, you were all about getting misted down today," said Cubs fan Corinne Dahlke.
As hot as it was to watch sports, playing was even tougher. The temperature of the artificial turf at one soccer field topped 100 degrees.
"Tired, hot, sweat a lot. We're usually drenched by the end of the game," said Sylvia Reyes, a soccer player.
Heat is on at Kane Co. Fair
At the Kane County Fair in west suburban St. Charles, the Lincoln Highway 4H Club members steered their prize swine to the corral to be judged Wednesday. And while the 100-plus heat index was top of mind for Jean Fabrizius and her brood of future farmers, it didn't stop anyone from performing
"Our number one priority is to keep our animals healthy, cool and safe. Our number one challenge along with that priority is to keep fans going and electricity here," said Fabrizius.
Nick Marco of Sandwich, Ill., is part of the 4-H program that started in earnest Wednesday when it felt like it was over 100 degrees in the shade.
"I care about them. I spent a lot of time on them," said Marco.Sixty thousand people are expected to visit the fair, which lasts through Sunday. Its president for a quarter century handled the heat with a farmer's cool.
"The hot weather will set us back a bit, but this is not the first hot weather of the season. People are a little used to it," said Larry Breon, Kane Co. Fair president.
In the western suburbs, where there's no Lake Michigan to mitigate the effect of the heat, Glen Ellyn's Ackerman sports complex sat ready to welcome weary athletes. But former Chicago Fire star Brian McBride's campers braved the elements with water breaks every 10 minutes.
"We definitely serve a lot of balls but we have had a great attitude through it and haven't given up once, so I'm proud of them," said McBride.
"It makes you more challenged and just shows how good you are, but I don't really mind it much. It is the cold that gets to me," said Tess Sobol, soccer camper.
That kind of focus turned to recreation as the general public descended on Lombard's big public pool , as the facility approved by referendum earned goodwill from the taxpayers who thought of days like this back at election time.
"This is the best $5 million investment. It was worth every penny," said swimmer Bob Schmitt.
Brief power outage in Chicago's Gold Coast neighborhood
Hundreds of residents on the city's Near North Side had to suffer without power Wednesday for a short time in the intense heat. About 500 customers lost power around 1 p.m.
Most of those ComEd customers were scattered about the River North and Streeterville neighborhoods. It appears the outage was related to some sort of equipment failure and not early morning storms that rolled through parts of the area.
Among the buildings without power were high-rises like the Four Points Sheraton on North Rush and a condo on East Pearson.
ComEd was able to restore power after 40 minutes in some cases and in an hour in other cases. Of course, with the heat index at more than 100 degrees, going any time without electricity can be dangerous and that's why the customers ABC7 spoke to said they were thankful for ComEd's quick response.
"I think the guests' safety is most important," said hotel manager A.J. Karsten. "You want to make sure all hands are on deck and everyone is remaining calm, especially on such a hot day, and we have all managers on the floor and called the right people to come out here, just to make sure everything was smooth and no one panicked."
That early morning storm did affect thousands of ComEd customers. About 6,000 customers throughout the ComEd area were without power. Representatives said late Wednesday afternoon they are working hard to get them all up and running.