Chillicothe, IL Weather & Growing Conditions
Today
84°F
Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 11am, then a slight chance of showers and thunderstorms between 11am and 1pm. Mostly cloudy, with a high near 84. Southeast wind around 7 mph. Chance of precipitation is 30%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 7 mph SE | 26% |
| Tonight | 67°F | Showers And Thunderstorms Likely | 5 mph SW | 80% |
| Sunday | 73°F | Showers And Thunderstorms Likely | 5 to 15 mph N | 72% |
| Sunday Night | 58°F | Chance Showers And Thunderstorms | 14 to 17 mph NE | 55% |
| Monday | 65°F | Showers And Thunderstorms Likely | 17 mph ENE | 64% |
| Monday Night | 53°F | Chance Rain Showers | 13 to 17 mph NE | 45% |
| Tuesday | 63°F | Slight Chance Rain Showers | 16 mph NE | 23% |
| Tuesday Night | 51°F | Partly Cloudy | 7 to 15 mph NNE | 11% |
| Wednesday | 67°F | Mostly Sunny | 12 mph NNE | 4% |
| Wednesday Night | 53°F | Partly Cloudy | 3 to 9 mph NNE | 1% |
| Thursday | 69°F | Mostly Sunny | 7 mph NNE | 4% |
| Thursday Night | 54°F | Mostly Cloudy | 6 mph NE | 4% |
| Friday | 72°F | Mostly Sunny | 5 to 8 mph NE | 3% |
| Friday Night | 54°F | Partly Cloudy | 6 mph ENE | 2% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Chillicothe, IL
Last spring frost
Apr 22
First fall frost
Oct 14
Growing season
174 days
Hardiness zone
5b
Explore more for Chillicothe, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Princeville, Il (7.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.