DeWitt Iowa Climate Data

Monthly Average Climate Data for DeWitt Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January12.8 °F29.3 °F1.36 in.
February16.5 °F33.8 °F1.65 in.
March27.4 °F46.7 °F2.41 in.
April38.4 °F60.3 °F3.77 in.
May50.4 °F71.5 °F4.72 in.
June60.4 °F80.8 °F4.8 in.
July63.9 °F83.7 °F4.31 in.
August61.6 °F81.8 °F4.36 in.
September53.3 °F76.1 °F3.69 in.
October41.5 °F63.1 °F2.89 in.
November29.6 °F48.0 °F2.19 in.
December19.2 °F34.9 °F1.84 in.
Annual39.6 °F59.2 °F37.99 in.

Climate Data for DeWitt Iowa

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
Average Days With Frost75-100 Days
Plant Hardiness Zone - 2023Zone 5b : -15°F to -10°F
Plant Hardiness Zone - 2012Zone 5a : -20°F to -15°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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