CHICAGO (STMW) – A freeze warning has been issued as a cold, dry air mass is expected to move into the Chicago area early Saturday, bringing below-freezing temperatures that could kill sensitive vegetation.

A freeze warning will be in effect from 2 a.m. until 9 a.m. Saturday for portions of northern Illinois, including DeKalb, DuPage, Kane, Lake, McHenry and Will counties, according to the National Weather Service’s website.

A dry air mass is expected to move into the Chicago area early Saturday that will drop temperatures to below freezing in much of the area, the weather service said. Urban areas and locations along the immediate lakefront are expected to remain above freezing.

The temperature in the effected areas is expected to be in the upper-20s, with isolated regions dropping into the mid-20s, the weather service said.

The several hours of below-freezing temperatures will kill sensitive plans and vegetation, the weather service said.

In Chicago, the low is only expected to be in the mid-30s early Saturday, the weather service said. Low temperatures in the upper-30s to mid-40s are expected through Tuesday. High temperatures will consistently be in the mid- to upper-50s.

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