Precipitation was near normal for the month of October in Illinois, at a statewide average of 3.2 inches. The long-term average, or normal, for October is 3.26 inches of precipitation, according to Illinois State Climatologist Jim Angel at the Illinois State Water Survey, Prairie Research Institute, University of Illinois.
Most of this precipitation fell in the last few days of the month. The heaviest amounts were in Cook, Will, and Kankakee counties along with some areas in far southern Illinois. The largest reported monthly total was 6.79 inches at Bourbonnais.
Many sites across northern and central Illinois reported their first snow of the season in October. The highest monthly snowfall total was at Mendota with 3.5 inches. Several more sites reported 1 to 2.5 inches of snow for the month.
Temperatures were just 0.3 degrees below normal with a statewide value of 54.3 degrees. However, the first half of the month was 5.5 degrees above normal, while the second half was 5.9 degrees below normal. Most of the state saw temperatures dropping below freezing for the first time this fall on October 21-22.
“The late October rains were large enough and widespread enough to help recharge soil moisture after the exceptional dryness of the last three months,” concludes Angel.
