Belleville Illinois Climate Data

Monthly Average Climate Data for Belleville Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January23.5 °F39.9 °F2.84 in.
February27.0 °F45.3 °F2.45 in.
March35.7 °F55.5 °F3.61 in.
April46.4 °F67.4 °F5.01 in.
May57.2 °F76.4 °F5.23 in.
June66.1 °F85.3 °F5.12 in.
July69.9 °F88.5 °F4.33 in.
August67.9 °F87.3 °F3.8 in.
September59.5 °F80.8 °F3.38 in.
October48.2 °F69.3 °F3.23 in.
November36.7 °F55.2 °F3.74 in.
December28.1 °F44.3 °F2.91 in.
Annual47.2 °F66.3 °F45.65 in.

Climate Data for Belleville Illinois

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost75-100 Days
Plant Hardiness Zone - 2023Zone 7a : 0°F to 5°F
Plant Hardiness Zone - 2012Zone 6b : -5°F to 0°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationCfa - Humid Subtropical Climate