Winnetka Illinois Climate Data

Monthly Average Climate Data for Winnetka Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January18.9 °F31.8 °F2.14 in.
February21.7 °F35.5 °F2.04 in.
March30.3 °F45.0 °F2.19 in.
April40.1 °F56.5 °F3.8 in.
May50.3 °F67.7 °F4.6 in.
June60.5 °F77.6 °F4.31 in.
July67.2 °F82.3 °F3.72 in.
August66.8 °F80.8 °F4.08 in.
September59.3 °F74.2 °F3.51 in.
October46.9 °F62.5 °F3.49 in.
November35.1 °F48.3 °F2.63 in.
December24.9 °F37.0 °F2.28 in.
Annual43.5 °F58.3 °F38.79 in.

Climate Data for Winnetka Illinois

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 6a : -10°F to -5°F
Plant Hardiness Zone - 2012Zone 5b : -15°F to -10°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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