Winthrop Harbor Illinois Climate Data

Monthly Average Climate Data for Winthrop Harbor Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-8.8 °C-1 °C49.28 mm
February-7.3 °C0.7 °C48.01 mm
March-2.3 °C5.8 °C58.42 mm
April3.1 °C11.6 °C100.58 mm
May8.6 °C17.7 °C107.44 mm
June14.2 °C23.2 °C104.39 mm
July17.9 °C26.5 °C88.65 mm
August17.6 °C25.9 °C89.92 mm
September13.3 °C22.3 °C86.87 mm
October6.8 °C15.7 °C81.03 mm
November0.3 °C8.4 °C60.45 mm
December-5.4 °C2.1 °C52.58 mm
Annual4.8 °C13.2 °C927.62 mm

Climate Data for Winthrop Harbor Illinois

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateMay 11 - May 20
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 6a : -23.3°C to -20.6°C
Plant Hardiness Zone - 2012Zone 5b : -26.1°C to -23.3°C
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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