Williamson Iowa Climate Data

Monthly Average Climate Data for Williamson Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-10.4 °C-0.3 °C25.91 mm
February-8.2 °C2.3 °C35.05 mm
March-2.3 °C9.5 °C53.85 mm
April3.7 °C16.3 °C102.36 mm
May10.3 °C21.8 °C138.94 mm
June15.9 °C27.1 °C134.62 mm
July18.2 °C29.5 °C117.09 mm
August16.7 °C28.5 °C112.52 mm
September11.8 °C24.8 °C94.23 mm
October5.1 °C17.8 °C71.63 mm
November-1.6 °C9.4 °C51.05 mm
December-7.2 °C2.7 °C35.56 mm
Annual4.3 °C15.8 °C972.81 mm

Climate Data for Williamson Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 21 - May 31
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 5b : -26.1°C to -23.3°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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