Diagonal, IA Weather & Growing Conditions
Tonight
44°F
Rain Showers Likely then Cloudy
Rain showers likely before 9pm. Cloudy. Low around 44, with temperatures rising to around 46 overnight. Northwest wind 12 to 16 mph, with gusts as high as 23 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 44°F | Rain Showers Likely then Cloudy | 12 to 16 mph NW | 61% |
| Wednesday | 52°F | Mostly Cloudy | 13 to 16 mph W | 13% |
| Wednesday Night | 40°F | Mostly Cloudy | 10 mph W | 6% |
| Thursday | 52°F | Chance Rain Showers | 12 mph NW | 35% |
| Thursday Night | 39°F | Mostly Cloudy | 8 mph NNW | 11% |
| Friday | 52°F | Partly Sunny | 3 to 7 mph N | 5% |
| Friday Night | 34°F | Mostly Cloudy | 2 mph N | 0% |
| Saturday | 56°F | Mostly Sunny | 1 to 5 mph WSW | 3% |
| Saturday Night | 37°F | Mostly Clear | 5 mph W | 5% |
| Sunday | 62°F | Sunny | 6 mph W | 4% |
| Sunday Night | 39°F | Mostly Clear | 6 mph SW | 0% |
| Monday | 65°F | Sunny | 6 to 12 mph SW | 0% |
| Monday Night | 41°F | Mostly Clear | 6 mph WNW | 0% |
| Tuesday | 65°F | Sunny | 6 mph NE | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Diagonal, IA
Last spring frost
Apr 25
First fall frost
Oct 12
Growing season
169 days
Hardiness zone
5b
Explore more for Diagonal, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Mt Ayr, Ia (9.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.