Norwalk Iowa Climate Data

Monthly Average Climate Data for Norwalk Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-10.4 °C-0.7 °C25.91 mm
February-8.3 °C1.9 °C31.75 mm
March-2.2 °C9.1 °C51.82 mm
April4.1 °C16.4 °C93.22 mm
May10.7 °C22.2 °C131.06 mm
June16.4 °C27.5 °C130.05 mm
July18.6 °C29.7 °C104.39 mm
August17.2 °C28.8 °C104.14 mm
September12.3 °C25.1 °C87.38 mm
October5.4 °C17.8 °C65.28 mm
November-1.3 °C9.3 °C45.47 mm
December-7.3 °C2.2 °C36.58 mm
Annual4.6 °C15.8 °C907.05 mm

Climate Data for Norwalk Iowa

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
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 ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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