Jan 17 | Climate Review and Weather Forecast
January continued its cold pattern this week. Average temperatures ranged from the mid teens to the high 20s across the state, between 4 and 12 degrees below normal. Some of the more impressive nighttime low temperatures this week included -7 degrees in Aurora and -6 degrees in Champaign. The first half of the month has at least felt quite cold, and has been colder than normal; however, this month so far is only among the top 40 to 50 coldest on record in Illinois.
Another winter system moved across the southern and eastern halves of the state late last week and last weekend, bringing another round of significant snowfall. Parts of southern Illinois picked up several inches of snow, including almost 8 inches in Carbondale. The northern and northwest parts of the state remained mostly snowfree yet again, with accumulation mostly less than a quarter of an inch. Snowfall since October has been 4 to 10 inches above normal in southern and south-central Illinois, and 6 to 12 inches below normal in northern Illinois. The 3.2 inches of total snowfall in Moline since October is the 10th lowest total on record and the least snowfall there since 2003. Meanwhile, the 19 inches of snowfall so far this season in Fairfield is the 2nd highest on record there and the highest total since 1918.
Looking ahead, temperatures will rise Friday into Saturday before dropping off a cliff early next week. Some parts of southern Illinois may even see high temperatures break into the 50s on Saturday, with rain totals between a tenth and a half an inch. But, high temperatures on Monday and Tuesday will struggle to make the double digits statewide, and nighttime lows on Monday and Tuesday will be well into the negatives, including -10 degrees expected in northern Illinois. Farther out, the week 2 outlook still shows below normal temperatures through the end of the month, with maybe some better chances of precipitation across the state. The latest outlooks for February and the transition period between winter and spring dropped this week, both showing strong chances of wetter than normal conditions, as the models and outlooks lean into La Nina.