Savanna Illinois Climate Data

Monthly Average Climate Data for Savanna Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January12.4 °F29.2 °F1.51 in.
February16.2 °F33.8 °F1.71 in.
March27.1 °F46.4 °F2.34 in.
April37.7 °F60.1 °F3.75 in.
May49.5 °F71.5 °F4.5 in.
June59.4 °F80.9 °F5.33 in.
July62.8 °F84.2 °F4.49 in.
August60.5 °F82.1 °F3.95 in.
September52.0 °F75.9 °F3.65 in.
October40.6 °F62.9 °F2.88 in.
November29.3 °F47.4 °F2.29 in.
December19.0 °F34.7 °F1.92 in.
Annual38.9 °F59.1 °F38.32 in.

Climate Data for Savanna Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateMay 1 - May 10
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 5a : -20°F to -15°F
Plant Hardiness Zone - 2012Zone 5a : -20°F to -15°F
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
2024 plantmaps.com