Williamson Iowa Climate Data

Monthly Average Climate Data for Williamson Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January13.3 °F31.5 °F1.02 in.
February17.2 °F36.1 °F1.38 in.
March27.9 °F49.1 °F2.12 in.
April38.7 °F61.4 °F4.03 in.
May50.6 °F71.2 °F5.47 in.
June60.6 °F80.8 °F5.3 in.
July64.8 °F85.1 °F4.61 in.
August62.1 °F83.3 °F4.43 in.
September53.2 °F76.7 °F3.71 in.
October41.1 °F64.0 °F2.82 in.
November29.1 °F49.0 °F2.01 in.
December19.1 °F36.8 °F1.4 in.
Annual39.8 °F60.4 °F38.3 in.

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 : -15°F to -10°F
Plant Hardiness Zone - 2012Zone 5a : -20°F to -15°F
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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