Janesville Iowa Climate Data

Monthly Average Climate Data for Janesville Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-12.8 °C-3.3 °C25.91 mm
February-10.4 °C-0.8 °C28.45 mm
March-4.1 °C6.6 °C50.04 mm
April2.5 °C14.7 °C100.33 mm
May9.4 °C21.3 °C124.46 mm
June15.4 °C26.8 °C146.81 mm
July17.2 °C28.4 °C115.06 mm
August15.6 °C27.3 °C104.39 mm
September10.7 °C24 °C88.9 mm
October3.8 °C16.5 °C72.14 mm
November-3.1 °C7.4 °C48.01 mm
December-8.9 °C0 °C39.12 mm
Annual2.9 °C14.1 °C943.62 mm

Climate Data for Janesville Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 21 - May 31
Average Days With Frost150-180 Days
Plant Hardiness Zone - 2023Zone 5a : -28.9°C to -26.1°C
Plant Hardiness Zone - 2012Zone 5a : -28.9°C to -26.1°C
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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