Williamson, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Williamson, a village in Madison County, Illinois.

Overnight

54°F

Chance Light Rain

A chance of rain. Mostly cloudy, with a low around 54. Southwest wind 9 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.

7-day forecast for Williamson

When	Temp	Forecast	Wind	Precip
Overnight	54°F	Chance Light Rain	9 to 14 mph SW	51%
Wednesday	61°F	Slight Chance Drizzle then Mostly Cloudy	8 to 14 mph W	12%
Wednesday Night	43°F	Partly Cloudy	3 to 7 mph W	1%
Thursday	62°F	Mostly Sunny	5 to 12 mph W	0%
Thursday Night	43°F	Mostly Cloudy	5 mph NW	1%
Friday	55°F	Partly Sunny	6 to 10 mph N	2%
Friday Night	33°F	Partly Cloudy	2 to 7 mph N	0%
Saturday	54°F	Mostly Sunny	5 mph N	0%
Saturday Night	32°F	Partly Cloudy	2 mph NW	0%
Sunday	60°F	Sunny	1 to 7 mph NW	1%
Sunday Night	34°F	Clear	2 mph W	0%
Monday	64°F	Sunny	0 to 6 mph SW	0%
Monday Night	38°F	Clear	2 mph SW	0%
Tuesday	67°F	Sunny	5 mph W	1%

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

More local growing data for Williamson: nearby ZIP 62058 weather · frost dates · planting calendar · Illinois frost dates

Nearby towns & communities

Alhambra Alton Bethalto Collinsville East Alton Edwardsville Glen Carbon Godfrey Granite City Grantfork Hamel Hartford Highland Holiday Shores Livingston Madison Marine Maryville Mitchell Moro New Douglas Pontoon Beach Prairietown Rosewood Heights Roxana South Roxana St. Jacob Troy Venice Wood River

All Illinois locations ›

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.