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Diagonal, IA Weather & Growing Conditions

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

Tonight
62°F
Chance Showers And Thunderstorms then Showers And Thunderstorms Likely
A chance of showers and thunderstorms before 11pm, then showers and thunderstorms likely between 11pm and 2am, then a chance of showers and thunderstorms between 2am and 4am, then a chance of showers and thunderstorms. Mostly cloudy. Low around 62, with temperatures rising to around 65 overnight. North wind 7 to 10 mph. Chance of precipitation is 70%. New rainfall amounts between a half and three quarters of an inch possible.

7-day forecast for Diagonal

WhenTempForecastWindPrecip
Tonight 62°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 7 to 10 mph N 67%
Sunday 66°F Chance Showers And Thunderstorms 7 to 12 mph NNE 44%
Sunday Night 57°F Showers And Thunderstorms Likely 8 to 12 mph NE 65%
Monday 60°F Rain Showers Likely 12 mph NE 70%
Monday Night 52°F Rain Showers Likely 7 to 10 mph NNE 66%
Tuesday 59°F Mostly Cloudy 8 mph NE 7%
Tuesday Night 46°F Mostly Cloudy 3 to 7 mph NE 3%
Wednesday 62°F Mostly Sunny 5 mph ENE 0%
Wednesday Night 51°F Partly Cloudy 3 mph E 11%
Thursday 65°F Slight Chance Rain Showers 3 mph SE 23%
Thursday Night 57°F Slight Chance Rain Showers 2 mph ESE 23%
Friday 68°F Slight Chance Rain Showers 5 mph ESE 23%
Friday Night 59°F Slight Chance Rain Showers 5 mph E 19%
Saturday 68°F Chance Rain Showers 5 to 8 mph SE 26%

Forecast source: National Weather Service (api.weather.gov) for Diagonal (40.811, -94.342). Updated through the day.

Growing snapshot for Diagonal

Last spring frost
Apr 25
First fall frost
Oct 12
Growing season
169 days
Hardiness zone
5b

More local growing data for Diagonal: nearby ZIP 50845 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Mt Ayr, Ia (9.5 mi from Diagonal). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.