The average statewide temperature for the three core winter months of December, January, and February was 20.8 degrees. It was 8.2 degrees below average and the fourth coldest December-February period on record, according to Illinois State Climatologist Jim Angel at the Illinois State Water Survey, University of Illinois.
This winter was in a three-way tie with 1917-1918 and 1976-1977. The coldest winter was 1977-1978 at a statewide average temperature of 19.6 degrees. The winter of 1978-1979 was in second place at 19.9 degrees.
The Illinois statewide temperature for February was 18.7 degrees, or 12.1 degrees below the long-term average. It was the seventh coldest February on record.
The snowfall for February was above average across the state. The total snowfall ranged from 4 inches in far southern Illinois to 15 to 20 inches in north-central Illinois. The snowfall departures from average ranged from 1 to 5 inches south of Interstate 70 and between 10 and 18 inches between Interstates 70 and 80.
The statewide precipitation for February was 2.28 inches, which is 0.17 inches above average. Precipitation includes both rain events along with the water content of any snowfall. The result in February was that the above-average snowfall did not translate to above-average precipitation because several of those snowfall events occurred in colder conditions when the snow density was lower (i.e., fluffier snow).
Snowfall this winter so far has been above average across the state. Snowfall totals ranged from 10 inches in the southernmost counties of the state to over 60 inches in the northeast. Some of the largest snowfall totals this entire winter were in the Chicago area and included Lincolnwood with 79.8 inches and Oak Park with 78.6 inches.
“This winter was comparable to the winters in the late 1970s in terms of the cold weather and snow,” concludes Angel.