Quincy Average Temperature by Month

This page shows the average temperature in each month of the year in Quincy, Illinois. It is based on NOAA data for the years 1991–2020.
What's the Hottest Month in Quincy?
In Quincy, Illinois, the warmest month is July, with an average daily high temperature of 86.0 °F and an average low of 66.5 °F.
What's the Coldest Month in Quincy?
In Quincy, Illinois, the coolest month is January, with an average daily high temperature of 34.6 °F and an average low of 18.6 °F.
Month Avg. High Avg. Low
January 34.6 °F 18.6 °F
February 39.7 °F 22.6 °F
March 51.7 °F 32.4 °F
April 63.7 °F 42.8 °F
May 73.3 °F 53.9 °F
June 82.4 °F 63.1 °F
July 86.0 °F 66.5 °F
August 84.5 °F 64.5 °F
September 78.0 °F 56.1 °F
October 65.4 °F 44.8 °F
November 51.2 °F 33.4 °F
December 39.3 °F 23.9 °F
Year 62.6 °F 43.7 °F
Weather Station Details
Years Station Coordinates
1949–2024 Quincy Regional Airport location
1901–1948 Quincy location