Harman US

Iroquois, IL Weather & Growing Conditions

Tonight
63°F
Mostly Cloudy then Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 5am. Mostly cloudy, with a low around 63. East wind 5 to 10 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Tonight 63°F Mostly Cloudy then Slight Chance Showers And Thunderstorms 5 to 10 mph E 17%
Saturday 82°F Showers And Thunderstorms Likely 5 to 10 mph SE 58%
Saturday Night 68°F Chance Showers And Thunderstorms 5 mph WSW 64%
Sunday 76°F Showers And Thunderstorms Likely 5 to 10 mph NNE 67%
Sunday Night 55°F Showers And Thunderstorms Likely 10 mph NE 65%
Monday 66°F Showers And Thunderstorms Likely 10 mph ENE 65%
Monday Night 50°F Chance Showers And Thunderstorms 10 mph NE 41%
Tuesday 66°F Slight Chance Rain Showers 10 mph NE 23%
Tuesday Night 50°F Slight Chance Rain Showers then Mostly Cloudy 5 to 10 mph NNE 18%
Wednesday 68°F Partly Sunny 5 mph NNE 7%
Wednesday Night 51°F Mostly Cloudy 0 to 5 mph NNE 7%
Thursday 70°F Partly Sunny 0 to 5 mph NNE 3%
Thursday Night 52°F Mostly Cloudy 0 to 5 mph NNE 3%
Friday 72°F Mostly Sunny 0 to 5 mph NNE 3%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Iroquois, IL

Last spring frost
Apr 24
First fall frost
Oct 16
Growing season
174 days
Hardiness zone
5b

Explore more for Iroquois, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Watseka 2 Nw, Il (8.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.