Chillicothe, IL Weather & Growing Conditions
Tonight
45°F
Slight Chance Drizzle then Mostly Cloudy
A slight chance of drizzle before 10pm. Mostly cloudy, with a low around 45. Southwest wind around 10 mph, with gusts as high as 18 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 45°F | Slight Chance Drizzle then Mostly Cloudy | 10 mph SW | 10% |
| Thursday | 55°F | Mostly Cloudy then Chance Light Rain | 7 to 14 mph W | 33% |
| Thursday Night | 39°F | Slight Chance Light Rain then Cloudy | 8 mph NNW | 21% |
| Friday | 49°F | Mostly Sunny | 6 to 10 mph N | 2% |
| Friday Night | 30°F | Mostly Clear | 0 to 5 mph NNW | 0% |
| Saturday | 51°F | Sunny | 0 to 3 mph NW | 0% |
| Saturday Night | 32°F | Mostly Clear | 1 mph W | 0% |
| Sunday | 58°F | Sunny | 1 to 6 mph W | 0% |
| Sunday Night | 34°F | Mostly Clear | 2 mph W | 0% |
| Monday | 62°F | Sunny | 0 to 8 mph SW | 0% |
| Monday Night | 39°F | Clear | 2 to 6 mph WSW | 0% |
| Tuesday | 63°F | Sunny | 3 mph WNW | 2% |
| Tuesday Night | 39°F | Mostly Clear | 1 mph NNW | 1% |
| Veterans Day | 62°F | Mostly Sunny | 0 to 5 mph N | 2% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Chillicothe, IL
Last spring frost
Apr 20
First fall frost
Oct 17
Growing season
178 days
Hardiness zone
6a
Explore more for Chillicothe, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Lacon, Il (9.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 5, 2026.