Carbondale, Illinois – Arctic air is expected to remain an influence across southern Illinois from Jan. 24 through Jan. 30, though the cold signal is weaker than across northern parts of the Midwest as the region sits closer to the southern edge of the broader winter pattern.
According to the National Weather Service Climate Prediction Center, southern Illinois falls within a roughly 50 to 60 percent probability range for below-normal temperatures during the Jan. 24–30 period. This suggests colder-than-average conditions are still favored overall, but with greater day-to-day variability and occasional moderation, especially during afternoon hours.
Across the southern tier, including Carbondale, Marion, and Mount Vernon, daytime highs are expected to dip below late-January averages at times, while overnight lows frequently fall into the teens and 20s. Cold nighttime temperatures could allow icy patches to persist on bridges, overpasses, and untreated roads along Interstates 57 and 64, particularly during early morning travel.
In far southern and western areas near the Mississippi and Ohio rivers, slightly milder air may briefly move in at times. Even so, temperatures are still expected to cool enough overnight to support refreezing where moisture remains on roadways and sidewalks.
The Illinois Department of Transportation urges drivers to remain cautious during morning and nighttime travel, when slick spots are most likely. Residents are encouraged to monitor temperature swings, protect exposed pipes during colder nights, and remain weather-aware.
While confidence is lower than farther north, the broader Arctic pattern remains influential, keeping below-normal temperatures a continued possibility across southern Illinois through Jan. 30.
