Alton Iowa Climate Data

Monthly Average Climate Data for Alton Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January8.5 °F26.7 °F0.73 in.
February12.8 °F31.5 °F0.78 in.
March24.1 °F44.3 °F1.73 in.
April35.1 °F59.1 °F3.01 in.
May48.0 °F71.2 °F3.98 in.
June59.0 °F81.1 °F4.01 in.
July62.3 °F84.1 °F3.39 in.
August59.8 °F82.0 °F3.38 in.
September50.5 °F75.8 °F3.08 in.
October37.8 °F62.5 °F2.34 in.
November24.9 °F45.4 °F1.35 in.
December14.3 °F31.6 °F0.95 in.
Annual36.4 °F57.9 °F28.73 in.

Climate Data for Alton Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 1 - May 10
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 ConditionsSevere Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
2024 plantmaps.com