Northeastern Illinois and Northwest Indiana will see another sweltering day Tuesday, with even warmer temperatures, higher heat indices and an excessive heat warning. Tuesday will also see poor air quality due to elevated levels of ozone, and the chance for severe weather, the NBC 5 Storm Team said.
According to the National Weather Service, an excessive heat warning will go into effect at 12 p.m. Tuesday for the entire area. It’s set to expire at 10 p.m., the NWS said.
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The alert brings “dangerously hot conditions,” the NWS warned, with heat index values for most parts between 110 and 115 degrees.
High temperatures Tuesday will be in the upper 90s or even 100 degrees, NBC 5 Meteorologist Alicia Roman said, adding that the record high of 97 degrees, set in 1973, could be broken.
Such high temperatures and heat indices can “significantly” increase the potential for heat related illnesses, particularly for those outdoors, the NWS said.
“We’re going to sound like a broken record, but limit your time outside, stay hydrated and drink lots and lots of water,” Roman said.
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According to the Chicago Office of Emergency Management and Communications, 250 cooling centers across the city will remain active through Tuesday. Chicago Public Schools, which started the 2024-25 school year Monday, announced all outdoor athletic games and matches would be canceled through Tuesday due to the heat.
But scorching temperatures aren’t the only part of Tuesday’s forecast.
Severe weather chances, air quality alert
Tuesday afternoon and evening will also see the chance for scattered, strong-to-severe thunderstorms, with the potential for heavy downpours, damaging winds and damaging hail, the NWS said.
According to the Storm Prediction Center, the entire area Tuesday night will be at a “slight” risk of severe weather, which ranks as level two on a scale of five.
An air quality alert also continues Tuesday for the entire Chicago area, including Northwest Indiana, the NWS said.
As of 5 a.m., the air quality measured at “moderate,” according to AirNow.gov, though Roman warned that the air quality was expected to worsen as the day continued.
“Moderate now, but later today, we will be upgraded to ‘unhealthy for some,’ which is level two of five,” Roman said.
Temperatures Wednesday were expected to drop into the 80s, Roman said, though humidity levels were expected to remain high.
“Still very muggy,” Roman said. “With dew point temperatures in the 70s, we still may have a heat index.”