Granite City Illinois Climate Data

Monthly Average Climate Data for Granite City Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January23.3 °F39.9 °F2.64 in.
February26.9 °F45.3 °F2.42 in.
March35.6 °F55.2 °F3.45 in.
April46.4 °F67.4 °F4.78 in.
May56.9 °F76.6 °F5.35 in.
June65.9 °F85.3 °F4.59 in.
July69.7 °F88.7 °F4.18 in.
August67.9 °F87.4 °F3.99 in.
September59.4 °F80.8 °F3.33 in.
October47.8 °F69.4 °F3.26 in.
November36.8 °F55.6 °F3.65 in.
December27.9 °F44.4 °F2.77 in.
Annual47 °F66.3 °F44.41 in.

Climate Data for Granite City Illinois

Average First Frost DateNov. 1 - Nov. 10
Average Last Frost DateApr. 11 - Apr. 20
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 ConditionsNormal
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation