Frost Advisory Issued as Temperatures Plummet Overnight

PEORIA, Ill. – A frost advisory is in effect overnight Wednesday into Thursday as temperatures are expected to dip significantly across several counties in Illinois and Missouri. The National Weather Service issued the advisory, which begins at midnight and lasts until mid-morning Thursday.

Residents in DeKalb, LaSalle, Grundy, and Kankakee counties should prepare for temperatures hovering around freezing. This could lead to frost formation, which poses a risk to sensitive outdoor plants. Experts recommend covering these plants or bringing them indoors when possible.

Thursday’s weather forecast predicts a mostly sunny day, with high temperatures only reaching the low-to-mid 50s. However, temperatures in areas farther from Chicago may drop below freezing, leading to even greater frost risk Thursday night into Friday morning.

In the Greater St. Louis area, frost advisories also apply to counties including Lincoln, Calhoun, Jersey, and Macoupin. Meteorologists have noted that even areas with temperatures above freezing can still see frost if surface temperatures cool sufficiently. The average first frost for St. Louis historically occurs around October 23, making this warning timely.

That winter chill isn’t likely to vanish anytime soon. Forecasts predict a return to the upper 30s overnight by Friday, with further frost risk. The NBC 5 Storm Team anticipates with caution, advising residents to remain vigilant about frost potential for subsequent nights.

Looking ahead to the weekend, significant warming is expected, with highs approaching 60 degrees on Saturday. Nonetheless, residents may need to stay prepared for rain showers starting late Sunday into Monday, potentially impacting Halloween festivities next week as temperatures are projected to be in the 50s.