Williamson, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Williamson, a village in Madison County, Illinois.
This Afternoon
58°F
Mostly Cloudy
Mostly cloudy, with a high near 58. West wind 7 to 10 mph.
7-day forecast for Williamson
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 58°F | Mostly Cloudy | 7 to 10 mph W | 0% |
| Tonight | 43°F | Mostly Cloudy | 6 mph SW | 0% |
| Thursday | 61°F | Mostly Sunny | 6 to 13 mph W | 9% |
| Thursday Night | 43°F | Isolated Rain Showers then Mostly Cloudy | 3 to 7 mph NW | 16% |
| Friday | 53°F | Partly Sunny | 7 to 12 mph N | 3% |
| Friday Night | 30°F | Mostly Clear | 2 to 6 mph N | 0% |
| Saturday | 53°F | Sunny | 5 mph N | 0% |
| Saturday Night | 30°F | Mostly Clear | 2 mph NW | 0% |
| Sunday | 58°F | Sunny | 1 to 5 mph W | 0% |
| Sunday Night | 33°F | Clear | 2 mph NW | 0% |
| Monday | 63°F | Sunny | 0 to 6 mph SW | 0% |
| Monday Night | 37°F | Clear | 2 mph SW | 0% |
| Tuesday | 64°F | Sunny | 3 mph W | 2% |
| Tuesday Night | 38°F | Mostly Clear | 1 mph N | 2% |
Forecast source: National Weather Service (api.weather.gov) for Williamson (38.985, -89.763). Updated through the day.
Growing snapshot for Williamson
Last spring frost
Apr 13
First fall frost
Oct 24
Growing season
192 days
Hardiness zone
6b
More local growing data for Williamson: nearby ZIP 62058 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
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Madison
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Climate data from the nearest NOAA station, Hillsboro, Il (19.8 mi from Williamson). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.