Frost advisory issued for Illinois as temperatures plummet overnight

The National Weather Service (NWS) has issued a frost advisory as temperatures are expected to drop further in Illinois.

The advisory for several counties, including Kankakee, LaSalle, DeKalb and Grundy will go into effect at midnight and remain in place through Thursday morning.

The NWS alert reveals that temperature is expected to reach freezing point in some areas that can produce frost. 

The alert warns that frost can harm the critical outdoor vegetation, urging residents to cover sensitive plants and take them indoors if possible.

For context, Frost is a deposit of soft, white ice crystals that forms on surfaces when the temperature drops below freezing. 

It is harmful to plants because it causes ice crystals to form inside their cells, which expands and ruptures the cell walls.

The forecast models suggest temperature on Wednesday will stay well above freezing point, however, the situation will change on Thursday night into Friday.

The temperatures are to reach below 50s on Friday night and a warmer Saturday is expected with mercury reaching above 60 degrees during the day in several counties of Chicago.

This comes amid communities around Chicago are planning to celebrate Halloween night on Friday, October 31. 

The forecast models reveal that temperature on the big night will be in the upper-50s with cloudy skies.