The Chicago area is bracing for some of the hottest temperatures of the season, and Sunday’s heat advisory is just the start of what could be a record-setting week in the region.
According to the National Weather Service, that heat advisory takes effect at 1 p.m. Sunday, and will remain in effect until 8 p.m.
Heat indices exceeding 100 degrees are possible in the impacted counties, which include McHenry, DeKalb, Kane, DuPage, LaSalle, Kendall, Grundy, Will and Kankakee counties in Illinois.
Southern Cook County is also included in that group.
Areas closer to Lake Michigan will see cooler temperatures, but elsewhere, highs will soar into the low-90s across the region.
That heat is just the beginning, as record-setting temperatures could occur later in the week. A heat advisory is set to go into effect from 11 a.m. to 9 p.m. Tuesday as heat index values of up to 109 are possible.
Here’s a day-by-day breakdown of what could be in store for the area.
Local
Sunday –
Sunday’s heat index could exceed 100 degrees in some locations, with officials urging residents to take frequent breaks indoors and to remain hydrated as much as possible.
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The heat should subside slightly heading into the evening as winds shift off the lake and a backdoor cold front descends across northeastern Illinois.
Monday –
The Sunday evening front will continue to keep temperatures a bit lower in most of the area, but highs will still be in the 80s and humidity will keep its grip on the area, albeit to a slightly-lesser degree.
Tuesday –
Winds will shift out of the south, ramping up the heat and humidity to even-more sweltering levels. Highs will rise into the low-90s across much of the area, with heat indices once again exceeding 100 degrees.
Wednesday/Thursday –
The week’s heat wave will hit its zenith on Wednesday and into Thursday, with record-breaking heat possible on both days.
In the city of Chicago, the record-high for Aug. 23 stands at 97 degrees, and was set during a remarkable heat wave in 1947. The high on Wednesday could potentially equal or exceed that number, according to the NBC 5 Storm Team.
Thursday’s record-high is 100 degrees on the nose, also set in 1947.
What’s more, heat indices could exceed 110 degrees in some locations, with a heat warning likely for the area as temperatures soar to levels not seen since a sustained heat wave in 2012.
Friday –
While temperatures are still expected to be warm to start Friday, a cold front is expected to bring showers and thunderstorms through the area in the morning hours, and that will spell an end to the heat wave.
In fact, high temperatures may struggle to reach 70 degrees on both Saturday and Sunday in the city of Chicago, giving residents some much-needed relief from the heat.