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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| 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
Nearby towns & communities
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.