The National Weather Service has issued a Frost Advisory for several counties across the Chicago area through Monday morning.
LaSalle, Grundy, Kankakee and Will counties in Illinois, as well as Lake, Porter, Newton and Jasper Counties in Indiana, are all under the advisory, which warns of low temperatures from 33 to 36 degrees.
The alert will take effect at midnight Monday and is scheduled to expire at 8 a.m. Residents are urged to take steps to protect tender plants from the cold, the NWS said.
Sunday began with rain showers in the morning and overall windy conditions. Rain continued into the afternoon before tapering off.
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The beginning of the work week is expected to be windy as well, with highs in the mid- to high 50s and partly sunny skies on Monday.