Marshalltown Iowa Climate Data

Monthly Average Climate Data for Marshalltown Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January10.8 °F27.7 °F1.03 in.
February14.6 °F32.4 °F1.15 in.
March25.8 °F45.4 °F2.04 in.
April37.1 °F59.7 °F3.8 in.
May49.6 °F70.9 °F5.08 in.
June60.3 °F80.6 °F5.41 in.
July63.5 °F83.8 °F4.29 in.
August60.7 °F81.7 °F4.23 in.
September51.9 °F75.8 °F3.51 in.
October39.7 °F62.2 °F2.61 in.
November27.6 °F46.6 °F1.93 in.
December17.0 °F33.4 °F1.47 in.
Annual38.2 °F58.4 °F36.55 in.

Climate Data for Marshalltown 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 ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation