Thunderstorms sweep through Chicago as hot, humid conditions to continue. Meanwhile, at least 7 tornadoes touched down Monday, meteorologists say.

Thunderstorms sweep through Chicago as hot, humid conditions to continue. Meanwhile, at least 7 tornadoes touched down Monday, meteorologists say.

At least seven tornadoes touched down during a harrowing three-hour period Monday evening, destroying a barn in Sycamore and downing trees throughout the far northwest suburbs, but there were no reports of fatalities or serious injuries, according to the National Weather Service.

Dangerous conditions persisted Tuesday with the chance of more thunderstorms that could spawn additional tornadoes, while the heat index was expected to make it feel as hot as 110 degrees, officials warned. A heat advisory was in place because of “dangerously hot temperatures and humid conditions” with the potential to lead to an increased risk of heat exhaustion or heat stroke, according to the weather service.

Around 8 p.m. Tuesday, a line of thunderstorms hit Chicago.

Hail is unlikely due to the heat and “the idea of a tornado is possible. That’s not the biggest concern tonight, though,” Lenning said.

There was a threat of flash flooding after potential thunderstorms and torrential downpours after midnight in areas south of Interstate 80, the weather service website said.

Tuesday’s high temperature reached 93 degrees around 2:37 p.m. at O’Hare International Airport.

Another heat advisory will be in place on Wednesday from noon to 7 p.m., Eric Lenning, a National Weather Service meteorologist, said Tuesday evening. Wednesday’s high temperature in Chicago is expected to reach 91, but the heat index could make it feel around 105, Lenning said.

He said people should stay inside, especially in the afternoon, and avoid the extreme heat.

“The thing that’s gonna affect the most people over the next day is the heat again tomorrow,” Lenning said. “So, you know, we don’t want to see anyone getting sick from the heat. We don’t want to see anyone having medical issues. It’s the type of heat that if you’re not careful, heat can kill people.”

In response to the high temperatures, the Chicago Office of Emergency Management and Communications announced locations of cooling centers across Chicago in a news conference Tuesday.

The following community service centers will operate as cooling centers from 9 a.m. to 5 p.m. Monday to Friday, according to Executive Director Richard Guidice: Englewood, Garfield, King, North Area, South Chicago and Trina Davila.

People can go to Garfield Community Service Center to get connected to shelter after hours.

In addition, senior centers, libraries and Chicago Park District facilities across the city will operate as cooling centers during regular hours of operation. Face coverings will be required at cooling centers.

“We urge residents to take extra efforts to check on their neighbors during extreme heat especially if they are seniors, families with young people, people with special needs, or living alone,” Guidice said.

Residents are advised to wear light and loose clothing, limit time outdoors and stay hydrated by drinking water and natural juices and avoiding alcoholic beverages, coffee and sodas, according to Brandie Knazze, the commissioner of the Department of Family and Support Services.

Residents can call 311 or visit 311.chicago.gov to locate cooling centers nearby.

People can register for Notify Chicago, the city’s extreme weather notification system, at notifychicago.org

The seven tornadoes that hit Monday were confirmed through a combination of photos, videos and reports from trained weather spotters, said Rafal Ogorek, a meteorologist at the weather service. That number can grow to about nine or 10 as crews continue to assess the storms from Monday night, Lenning said.

The confirmed tornado touchdowns were:

  • Near the Esmond area, right along the border of Ogle and DeKalb counties, northwest of the city of DeKalb, between 4:30 and 5 p.m.

  • South of Kirkland

  • North of Creston, south of Esmond, also near the Ogle and DeKalb County line

  • Burlington, in northwest Kane County, around 5:30 p.m.

  • In or near Sycamore in DeKalb County after 6 p.m., which “possibly lasted all the way until 6:30 or 6:45,” Ogorek said. “There might have been multiple touchdowns.”

  • Near Paw Paw in southeast Lee County around 6 p.m.

  • The town of McHenry in McHenry County 4:45 p.m. “It was just a very, very short tornado, just about a minute long,” Lenning said.

The tornado that touched down just outside Sycamore city limits was likely the most significant, Ogorek said. It caused damage between Bethany and Barbara Green roads and from Fenstermaker Road to Airport Road, according to Sycamore Deputy Fire Chief Art Zern.

“About half a dozen houses and several outbuildings, like storage buildings and barns, were damaged,” Zern said. “Nobody was injured, so that’s good news. Everybody made it to their basements in time after outdoor warning sirens went off in the area.”

The tornadoes struck a day before the anniversary of a rare derecho and tornadoes within Chicago city limits, which formed in Rogers Park on Aug. 10, 2020, and created a waterspout over Lake Michigan. Eleven tornadoes were confirmed from the system, which also uprooted massive trees and left nearly a million ComEd customers without power, some for days.

Ogorek said the height of severe weather season in northern Illinois runs most of the summer, from May to August. He said it’s not surprising the area had tornadoes touch down almost exactly a year apart.

“The specific dates may be a coincidence, but it’s not exactly unusual to get multiple tornadoes in August,” he said.

Thunderstorms and warm and humid conditions are expected to continue through the week with temperatures in the upper 80s and lower 90s through Thursday. Cooler and less humid conditions are expected by the weekend, with temperatures falling slightly to the lower to mid-80s Friday, according to the weather service’s website.

Check back for updates and for more on the forecast, visit the Tribune’s weather page.

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