Royal Iowa Climate Data

Monthly Average Climate Data for Royal Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January7.5 °F25.1 °F0.7 in.
February11.6 °F29.3 °F0.83 in.
March23.6 °F42.5 °F1.63 in.
April35.2 °F57.6 °F3.38 in.
May47.9 °F69.6 °F4.27 in.
June58.8 °F79.8 °F4.83 in.
July62.4 °F83.2 °F3.55 in.
August59.7 °F80.7 °F3.78 in.
September51.0 °F74.7 °F3.17 in.
October38.0 °F60.9 °F2.34 in.
November24.9 °F44.3 °F1.44 in.
December13.6 °F30.3 °F0.96 in.
Annual36.2 °F56.5 °F30.88 in.

Climate Data for Royal Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 11 - May 20
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 ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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