Harman US

Lake Summerset, IL Weather & Growing Conditions

Today
84°F
Mostly Sunny then Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 5pm. Mostly sunny. High near 84, with temperatures falling to around 80 in the afternoon. Southwest wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

7-day forecast

WhenTempForecastWindPrecip
Today 84°F Mostly Sunny then Slight Chance Showers And Thunderstorms 10 mph SW 16%
Tonight 64°F Showers And Thunderstorms Likely 5 mph WNW 84%
Wednesday 75°F Showers And Thunderstorms then Showers And Thunderstorms Likely 5 mph WNW 82%
Wednesday Night 58°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 0 to 5 mph NW 58%
Thursday 77°F Chance Rain Showers then Mostly Sunny 5 mph NE 26%
Thursday Night 58°F Mostly Clear 0 mph 7%
Friday 80°F Mostly Sunny 0 to 5 mph S 5%
Friday Night 62°F Mostly Clear 5 mph SSW 5%
Saturday 82°F Mostly Sunny 5 to 10 mph SSW 11%
Saturday Night 68°F Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms 10 mph SSW 23%
Sunday 84°F Slight Chance Showers And Thunderstorms 10 to 15 mph SW 23%
Sunday Night 67°F Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms 5 to 10 mph SW 43%
Monday 83°F Chance Showers And Thunderstorms 5 to 10 mph SSW 41%
Monday Night 67°F Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms 10 mph NW 42%

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

Growing snapshot for Lake Summerset, IL

Last spring frost
Apr 29
First fall frost
Oct 12
Growing season
165 days
Hardiness zone
5a

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

Climate data from the nearest NOAA station, Brodhead Wwtp, Wi (12.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.