Temperatures to drop by more than 20 degrees as T-storms move into Chicago area

CHICAGO (Sun-Times Media Wire) - An excessive heat warning remains in effect for the Chicago area through Sunday evening, when severe thunderstorms are expected to create a cool front that could cause temperatures to drop by more than 20 degrees.

The excessive heat warning remains in effect until 7 p.m. Sunday, according to the National Weather Service. Very humid air will make temperatures feel as high as 110 to 115 degrees during the daytime.

The temperatures can lead to potentially hazardous conditions, especially for the elderly and those with pre-existing heath conditions. The weather service warned residents to check on the elderly and those without air conditioning. Chicago residents can also call 311 for information about the city’s cooling centers or to request a well-being check for elderly friends or relatives.

Severe thunderstorms that could bring winds of up to 60 mph are expected to start pushing through northeast Illinois and northwest Indiana during the late afternoon and continue into the night, the weather service said. As a result, temperatures are expected to drop from the mid-90s to the low-70s.

The temporary reprieve from the weekend’s crippling heat will give way to hotter conditions heading into the Fourth of July holiday on Wednesday, according to the weather service.

Temperatures will remain a bit cooler on Monday, with a high of 85 and a low of 65, according to a local meteorologist. Near the lake, temperatures will stay in the 70s.

The National Weather Service is forecasting an 81 degree high for Tuesday and an 88 degree high for Independence Day.