Irwin, IA Weather & Growing Conditions
This Afternoon
77°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Mostly cloudy. High near 77, with temperatures falling to around 72 in the afternoon. North wind around 7 mph. Chance of precipitation is 30%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 77°F | Chance Showers And Thunderstorms | 7 mph N | 28% |
| Tonight | 58°F | Slight Chance Showers And Thunderstorms | 8 mph N | 22% |
| Sunday | 63°F | Chance Rain Showers | 8 to 12 mph NE | 45% |
| Sunday Night | 53°F | Rain Showers Likely | 7 to 10 mph NE | 70% |
| Monday | 58°F | Rain Showers | 9 mph NE | 83% |
| Monday Night | 49°F | Rain Showers Likely then Mostly Cloudy | 3 to 8 mph NE | 67% |
| Tuesday | 60°F | Mostly Cloudy | 3 to 7 mph NE | 5% |
| Tuesday Night | 45°F | Partly Cloudy | 0 to 5 mph ENE | 1% |
| Wednesday | 64°F | Mostly Sunny | 1 to 5 mph ESE | 1% |
| Wednesday Night | 51°F | Mostly Cloudy then Slight Chance Showers And Thunderstorms | 3 mph SE | 16% |
| Thursday | 66°F | Chance Showers And Thunderstorms | 2 to 7 mph SSE | 36% |
| Thursday Night | 56°F | Chance Rain Showers | 0 to 5 mph SE | 26% |
| Friday | 69°F | Slight Chance Rain Showers | 0 to 6 mph ESE | 20% |
| Friday Night | 58°F | Mostly Cloudy then Chance Rain Showers | 3 mph ESE | 25% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Irwin, IA
Last spring frost
Apr 27
First fall frost
Oct 9
Growing season
165 days
Hardiness zone
5a
Explore more for Irwin, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Harlan, Ia (11.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.