Flat Rock Illinois Climate Data

Monthly Average Climate Data for Flat Rock Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January22.0 °F38.1 °F3.2 in.
February24.9 °F43.0 °F2.49 in.
March33.4 °F53.7 °F3.63 in.
April43.8 °F66.1 °F5.08 in.
May54.7 °F75.9 °F4.93 in.
June63.4 °F84.5 °F4.87 in.
July66.0 °F87.4 °F4.3 in.
August63.7 °F86.5 °F3.12 in.
September55.9 °F81.1 °F3.47 in.
October44.5 °F68.9 °F3.65 in.
November34.3 °F54.3 °F3.82 in.
December26.4 °F42.6 °F3.22 in.
Annual44.4 °F65.2 °F45.78 in.

Climate Data for Flat Rock Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateMay 1 - May 10
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 6b : -5°F to 0°F
Plant Hardiness Zone - 2012Zone 6a : -10°F to -5°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
2024 plantmaps.com