January was wet with extreme winter conditions in Illinois

Mild weather carried over from Dec. into Jan. in Illinois, when frigid temperatures and winter storms hit mid-month. Rain and snowfall in Jan. took a big bite out of drought in the state, according to Illinois State Climatologist Trent Ford at the University of Illinois’ Illinois State Water Survey.

January precipitation tied for the eighth wettest on record.

Following a series of winter storms, cold air moved into the state, with actual temperatures of negative 25 degrees in Altona and negative 19 degrees in Moline. Strong northerly and northwesterly winds added to the cold and pushed wind chills into the negative 30 to negative 40-degree range. Water main breaks were reported across the state, and several school districts closed for multiple days because of the cold. Numerous deaths in the state were attributed to the cold as well.

The southern half of the state was one to three degrees colder than normal last month, and, despite the extreme cold in mid-month, northern Ill. was one to two degrees warmer than normal. The preliminary statewide average Jan. temperature was 25.7 degrees, one degree above the 1991–2020 average.

Drought impacts are usually minimal in winter, but even so there were many reports of unusually dry soils and low streams and ponds at the start of the new year. While January did not completely replenish all water lost last year, the persistent rain followed by wet, slowly melting snow returned moisture to the ground and started the climb out of drought. Much of the state was wetter than normal in January from one to four inches. The precipitation totals were especially impressive around the Ohio River. January's total precipitation ranged from around 2.5 inches in northwest Ill. to nearly ten inches in far southern Ill.

Total January snowfall ranged from less than half an inch in southern Ill. to more than 25 inches in northwest Ill. The latter area had four to 15 inches above normal snowfall.

Overall, the preliminary statewide average total for Jan. precipitation was 4.50 inches, 2.19 inches below the 1991–2020 average.

Outlooks for Feb. and for the spring season of March through May show higher chances of above normal temperatures. February’s outlook leans a bit more into El Niño with a nod to a drier final month of winter. Meanwhile, the March through May outlook is less confident on precipitation, with equal chances of a wet and dry spring.

For more information about monthly Ill. weather summaries, current conditions, and climate, visit the Illinois State Climatologist website, http://stateclimatologist.web.illinois.edu/.