Harman US

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

WhenTempForecastWindPrecip
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.