Thornton Iowa Climate Data

Monthly Average Climate Data for Thornton Iowa

Switch Data to Fahrenheit
MonthAvg. LowAvg. HighAvg. Precip
January-13.7 °C-4.2 °C23.11 mm
February-11.3 °C-1.6 °C26.92 mm
March-4.7 °C5.4 °C51.31 mm
April1.7 °C13.9 °C98.81 mm
May8.7 °C20.7 °C129.54 mm
June14.7 °C26.2 °C143 mm
July16.4 °C27.8 °C113.79 mm
August14.9 °C26.6 °C103.63 mm
September9.9 °C23.3 °C83.31 mm
October3.1 °C15.8 °C63.5 mm
November-3.7 °C6.6 °C43.69 mm
December-9.9 °C-1 °C34.29 mm
Annual2.2 °C13.3 °C914.9 mm

Climate Data for Thornton Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 21 - May 31
Average Days With Frost150-180 Days
Plant Hardiness Zone - 2023Zone 5a : -28.9°C to -26.1°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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