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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| 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.