CHICAGO (STMW) – A frost advisory has been issued for northern Illinois, and officials are advising sensitive vegetation be covered early Wednesday.

A frost advisory is in effect from 4 a.m. to 8 a.m. Wednesday for northern Illinois — including Cook, DeKalb, DuPage, Kane, Lake, McHenry and Will counties, according to the National Weather Service’s website.

Temperatures will drop into the low 30s early Wednesday when skies clear, the weather service said. The cold air and light wind should lead to areas of frost.

Areas along Lake Michigan, including Downtown Chicago, are expected to remain slightly warmer, and no frost is expected.

Frost can kill or damage sensitive vegetation, and the weather service advises appropriate actions should be taken.

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