DeWitt Iowa Climate Data

Monthly Average Climate Data for DeWitt Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-10.7 °C-1.5 °C34.54 mm
February-8.6 °C1 °C41.91 mm
March-2.6 °C8.2 °C61.21 mm
April3.6 °C15.7 °C95.76 mm
May10.2 °C21.9 °C119.89 mm
June15.8 °C27.1 °C121.92 mm
July17.7 °C28.7 °C109.47 mm
August16.4 °C27.7 °C110.74 mm
September11.8 °C24.5 °C93.73 mm
October5.3 °C17.3 °C73.41 mm
November-1.3 °C8.9 °C55.63 mm
December-7.1 °C1.6 °C46.74 mm
Annual4.2 °C15.1 °C964.95 mm

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 : -26.1°C to -23.3°C
Plant Hardiness Zone - 2012Zone 5a : -28.9°C to -26.1°C
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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