Leland Illinois Climate Data

Monthly Average Climate Data for Leland Illinois

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-10.1 °C-1.3 °C45.21 mm
February-8.1 °C1.2 °C44.7 mm
March-2.6 °C8.1 °C58.93 mm
April3.2 °C15.6 °C92.2 mm
May9.7 °C21.9 °C120.4 mm
June15.2 °C26.9 °C117.6 mm
July17.1 °C28.6 °C102.11 mm
August15.9 °C27.5 °C98.04 mm
September11.4 °C24.5 °C87.88 mm
October4.9 °C17.4 °C79.76 mm
November-1 °C9 °C63.5 mm
December-6.7 °C1.8 °C51.31 mm
Annual4.1 °C15.1 °C961.64 mm

Climate Data for Leland Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 5b : -26.1°C to -23.3°C
Plant Hardiness Zone - 2012Zone 5b : -26.1°C to -23.3°C
Current Drought ConditionsNormal
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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