West Branch Iowa Climate Data

Monthly Average Climate Data for West Branch Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-10.6 °C-1.3 °C32.51 mm
February-8.6 °C1.2 °C38.86 mm
March-2.5 °C8.4 °C58.93 mm
April3.7 °C16.3 °C95.25 mm
May10.3 °C22.2 °C120.4 mm
June15.9 °C27.3 °C132.08 mm
July17.8 °C29.2 °C109.47 mm
August16.4 °C28.2 °C107.19 mm
September11.7 °C24.8 °C89.66 mm
October5.1 °C17.6 °C75.18 mm
November-1.6 °C9 °C56.39 mm
December-7.3 °C1.6 °C43.69 mm
Annual4.2 °C15.4 °C959.61 mm

Climate Data for West Branch Iowa

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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