CHICAGO (AP) — A scorching heat wave will keep much of Illinois in the 90s or above this week.

The National Weather Service says a high pressure system will bring hot and humid conditions starting Sunday and lasting through most of the week.

The weather service on Sunday issued heat advisories, warnings and watches for counties statewide.

Temperatures will climb into the 90s, and the heat index may reach 100 degrees and higher in some areas. Nightfall won’t bring much of a reprieve as temperatures hover in the 70s at night.

The high temperatures could remain in the area through Friday.

Chicago officials say half a dozen cooling centers will be open this week.

The weather service suggests drinking water to stay hydrated and avoid spending a lot of time outdoors.

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