Knoxville, IL Weather & Growing Conditions
Today
88°F
Mostly Sunny
Mostly sunny, with a high near 88. South southwest wind around 8 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 88°F | Mostly Sunny | 8 mph SSW | 0% |
| Tonight | 67°F | Mostly Cloudy then Chance Showers And Thunderstorms | 5 mph SSE | 47% |
| Wednesday | 82°F | Chance Showers And Thunderstorms | 2 to 6 mph SSW | 72% |
| Wednesday Night | 64°F | Showers And Thunderstorms | 2 to 6 mph N | 83% |
| Thursday | 81°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 3 mph NE | 65% |
| Thursday Night | 63°F | Partly Cloudy | 2 mph NNE | 8% |
| Friday | 83°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 2 mph S | 16% |
| Friday Night | 65°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 1 mph SSE | 16% |
| Saturday | 86°F | Sunny | 2 to 6 mph SSW | 11% |
| Saturday Night | 70°F | Mostly Clear | 3 to 8 mph S | 9% |
| Sunday | 88°F | Sunny | 7 to 12 mph SSW | 7% |
| Sunday Night | 70°F | Partly Cloudy then Chance Showers And Thunderstorms | 6 to 10 mph S | 28% |
| Monday | 87°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 6 to 10 mph SSW | 28% |
| Monday Night | 71°F | Slight Chance Showers And Thunderstorms | 9 mph SSW | 29% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Knoxville, IL
Last spring frost
Apr 21
First fall frost
Oct 20
Growing season
181 days
Hardiness zone
5b
Explore more for Knoxville, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Knoxville, Il (3.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.