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Decatur, IA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Decatur, a city in Decatur County, Iowa.

Today
84°F
Partly Sunny
Partly sunny. High near 84, with temperatures falling to around 82 in the afternoon. West southwest wind 7 to 10 mph, with gusts as high as 21 mph. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Decatur

WhenTempForecastWindPrecip
Today 84°F Partly Sunny 7 to 10 mph WSW 13%
Tonight 64°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 2 to 7 mph N 67%
Sunday 68°F Chance Rain Showers then Chance Showers And Thunderstorms 8 to 12 mph NNE 49%
Sunday Night 58°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 10 mph NE 63%
Monday 61°F Showers And Thunderstorms Likely 12 mph NE 63%
Monday Night 52°F Chance Rain Showers 7 to 10 mph NE 43%
Tuesday 59°F Mostly Cloudy 9 mph NE 11%
Tuesday Night 47°F Partly Cloudy 3 to 7 mph NE 5%
Wednesday 63°F Mostly Sunny 6 mph ENE 2%
Wednesday Night 51°F Partly Cloudy 3 mph E 6%
Thursday 66°F Slight Chance Rain Showers 5 mph ESE 17%
Thursday Night 56°F Mostly Cloudy then Slight Chance Rain Showers 3 mph ESE 20%
Friday 68°F Slight Chance Rain Showers 6 mph E 20%
Friday Night 57°F Mostly Cloudy 5 mph ESE 12%

Forecast source: National Weather Service (api.weather.gov) for Decatur (40.743, -93.833). Updated through the day.

Growing snapshot for Decatur

Last spring frost
Apr 16
First fall frost
Oct 21
Growing season
186 days
Hardiness zone
5b

More local growing data for Decatur: nearby ZIP 50067 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Lamoni Muni Ap, Ia (4.2 mi from Decatur). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.