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Walnut, IA Weather & Growing Conditions

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

Overnight
70°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy. Low around 70, with temperatures rising to around 72 overnight. South southwest wind around 7 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Walnut

WhenTempForecastWindPrecip
Overnight 70°F Showers And Thunderstorms Likely 7 mph SSW 62%
Saturday 79°F Showers And Thunderstorms Likely 5 to 8 mph W 56%
Saturday Night 60°F Chance Showers And Thunderstorms 8 to 12 mph N 47%
Sunday 64°F Chance Rain Showers 13 mph NNE 41%
Sunday Night 55°F Chance Rain Showers 12 mph NE 37%
Monday 59°F Rain Showers Likely 12 mph NE 57%
Monday Night 50°F Chance Rain Showers then Mostly Cloudy 6 to 10 mph NE 53%
Tuesday 59°F Partly Sunny 8 mph ENE 3%
Tuesday Night 46°F Partly Cloudy 2 to 7 mph E 1%
Wednesday 63°F Mostly Sunny 6 mph ESE 1%
Wednesday Night 51°F Partly Cloudy then Slight Chance Rain Showers 5 mph ESE 16%
Thursday 64°F Chance Rain Showers 3 to 7 mph SE 27%
Thursday Night 55°F Mostly Cloudy then Slight Chance Rain Showers 5 mph SE 21%
Friday 66°F Slight Chance Rain Showers 5 to 8 mph ESE 21%

Forecast source: National Weather Service (api.weather.gov) for Walnut (41.489, -95.220). Updated through the day.

Growing snapshot for Walnut

Last spring frost
Apr 30
First fall frost
Oct 2
Growing season
153 days
Hardiness zone
5a

More local growing data for Walnut: nearby ZIP 51577 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Atlantic 1 Ne, Ia (10.8 mi from Walnut). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.