Trent Ford, Illinois State Climatologist, provided this weather update. Since the calendar turned over to 2025, we have been experiencing winter weather that, especially in southern Illinois, conjures memories of winters of yore. Average temperatures over the last 30 days ranged from the high teens in northwest Illinois to the high 30s in southeast Illinois, between 2 and 5 degrees below normal (Figure 1).

Meanwhile, the last 30-days have brought a lot of precipitation to southern Illinois, with totals ranging from 4 to 9 inches in most places south of Interstate 64. This continues a wet trend that going back to the start of December. In fact, Fairfield in Wayne County has had over 16 inches of precipitation since the start of climatological winter, already making this season the third wettest winter on record there.  While northern Illinois has been closer to normal precipitation over the last 30 days, central Illinois has had 1 to 3 inches less than normal precipitation going back to late January (Figure 2). 

Snowfall in 2025 has followed the wet-south, dry-north pattern we see in overall precipitation. Snowfall totals going back to October 1st range from less than 8 inches in northwest Illinois to just under 20 inches in south-central Illinois. Most of southern Illinois has seen around 200% of normal snowfall so far this season, compared to only 25-50% of normal snowfall in much of northern Illinois (Figure 3).