Belleville, IL Weather & Growing Conditions
Today
88°F
Sunny
Sunny, with a high near 88. Southeast wind around 3 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 88°F | Sunny | 3 mph SE | 0% |
| Tonight | 68°F | Mostly Clear | 5 mph SE | 0% |
| Wednesday | 90°F | Sunny | 2 to 7 mph S | 6% |
| Wednesday Night | 72°F | Slight Chance Showers And Thunderstorms | 7 mph S | 60% |
| Thursday | 88°F | Showers And Thunderstorms Likely | 6 mph S | 69% |
| Thursday Night | 71°F | Chance Showers And Thunderstorms | 3 mph SE | 43% |
| Friday | 88°F | Chance Showers And Thunderstorms | 5 mph SW | 43% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 3 mph SW | 35% |
| Saturday | 90°F | Chance Showers And Thunderstorms then Mostly Sunny | 5 mph S | 35% |
| Saturday Night | 72°F | Partly Cloudy | 6 mph S | 8% |
| Sunday | 92°F | Sunny | 5 to 8 mph S | 7% |
| Sunday Night | 73°F | Mostly Clear | 8 mph S | 5% |
| Monday | 94°F | Sunny | 8 mph SW | 5% |
| Monday Night | 75°F | Slight Chance Showers And Thunderstorms | 9 mph SW | 15% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Belleville, IL
Last spring frost
Apr 8
First fall frost
Oct 26
Growing season
200 days
Hardiness zone
7a
Explore more for Belleville, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Cahokia St Louis Ap, Il (5.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.