Belleville Average Temperature by Month

This page shows the average temperature in each month of the year in Belleville, Illinois. It is based on NOAA data for the years 1991–2020.
What's the Hottest Month in Belleville?
In Belleville, Illinois, the warmest month is July, with an average daily high temperature of 89.8 °F and an average low of 68.1 °F.
What's the Coldest Month in Belleville?
In Belleville, Illinois, the coolest month is January, with an average daily high temperature of 42.8 °F and an average low of 24.4 °F.
Month Avg. High Avg. Low
January 42.8 °F 24.4 °F
February 48.4 °F 28.0 °F
March 58.8 °F 36.5 °F
April 70.2 °F 46.2 °F
May 78.7 °F 56.4 °F
June 87.0 °F 64.7 °F
July 89.8 °F 68.1 °F
August 88.7 °F 65.4 °F
September 83.0 °F 57.3 °F
October 72.3 °F 46.6 °F
November 57.6 °F 36.9 °F
December 46.0 °F 28.4 °F
Year 68.7 °F 46.7 °F
Weather Station Details
Years Station Coordinates
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