Thornton Iowa Climate Data

Monthly Average Climate Data for Thornton Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January7.4 °F24.5 °F0.91 in.
February11.6 °F29.2 °F1.06 in.
March23.6 °F41.7 °F2.02 in.
April35.1 °F57.1 °F3.89 in.
May47.7 °F69.2 °F5.1 in.
June58.4 °F79.2 °F5.63 in.
July61.6 °F82.1 °F4.48 in.
August58.8 °F79.9 °F4.08 in.
September49.9 °F74.0 °F3.28 in.
October37.6 °F60.5 °F2.5 in.
November25.4 °F43.8 °F1.72 in.
December14.2 °F30.2 °F1.35 in.
Annual35.9 °F56 °F36.02 in.

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 : -20°F to -15°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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