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Marshalltown, IA Weather & Growing Conditions

Tonight
67°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 2am, then showers and thunderstorms likely. Mostly cloudy, with a low around 67. Southeast wind 7 to 10 mph. Chance of precipitation is 60%. New rainfall amounts between a half and three quarters of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Tonight 67°F Chance Showers And Thunderstorms 7 to 10 mph SE 61%
Saturday 80°F Showers And Thunderstorms Likely 8 mph SW 58%
Saturday Night 60°F Chance Showers And Thunderstorms 9 mph N 36%
Sunday 67°F Rain Showers Likely 9 to 13 mph NE 57%
Sunday Night 54°F Chance Showers And Thunderstorms 12 mph ENE 42%
Monday 62°F Rain Showers Likely 12 mph ENE 59%
Monday Night 50°F Rain Showers Likely 7 to 12 mph NE 59%
Tuesday 61°F Chance Rain Showers then Partly Sunny 8 mph NE 25%
Tuesday Night 46°F Partly Cloudy 2 to 6 mph NE 4%
Wednesday 65°F Mostly Sunny 3 mph ENE 1%
Wednesday Night 50°F Partly Cloudy 2 mph E 3%
Thursday 67°F Partly Sunny 2 mph ESE 12%
Thursday Night 53°F Partly Cloudy 2 mph ESE 9%
Friday 68°F Mostly Sunny 3 mph E 7%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Marshalltown, IA

Last spring frost
Apr 28
First fall frost
Oct 7
Growing season
162 days
Hardiness zone
5a

Explore more for Marshalltown, IA: full frost dates · planting calendar · Iowa frost dates

Climate data from the nearest NOAA station, Marshalltown, Ia (1.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.