Harman US

Clayton, IL Weather & Growing Conditions

Today
91°F
Mostly Cloudy
Mostly cloudy, with a high near 91. Southwest wind 6 to 9 mph.

7-day forecast

WhenTempForecastWindPrecip
Today 91°F Mostly Cloudy 6 to 9 mph SW 5%
Tonight 69°F Mostly Cloudy then Slight Chance Showers And Thunderstorms 5 mph SW 58%
Sunday 79°F Chance Showers And Thunderstorms 3 to 10 mph N 54%
Sunday Night 61°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 12 mph NE 72%
Monday 67°F Showers And Thunderstorms Likely 13 mph NE 72%
Monday Night 55°F Chance Rain Showers 12 mph NE 35%
Tuesday 64°F Chance Rain Showers 12 mph NE 26%
Tuesday Night 50°F Partly Cloudy 5 to 10 mph N 4%
Wednesday 68°F Mostly Sunny 8 mph N 1%
Wednesday Night 53°F Partly Cloudy 3 to 7 mph NE 1%
Thursday 71°F Partly Sunny 6 mph NE 4%
Thursday Night 56°F Partly Cloudy 5 mph NE 4%
Friday 73°F Mostly Sunny 3 to 7 mph NE 7%
Friday Night 56°F Partly Cloudy 6 mph NE 7%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Clayton, IL

Last spring frost
Apr 18
First fall frost
Oct 21
Growing season
187 days
Hardiness zone
6a

Explore more for Clayton, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Golden, Il (8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.