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South Wilmington, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for South Wilmington, a village in Grundy County, Illinois.

Today
83°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely before 8am, then showers and thunderstorms between 8am and 11am, then showers and thunderstorms likely. Cloudy. High near 83, with temperatures falling to around 81 in the afternoon. East southeast wind around 5 mph, with gusts as high as 15 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

7-day forecast for South Wilmington

WhenTempForecastWindPrecip
Today 83°F Showers And Thunderstorms Likely 5 mph ESE 80%
Tonight 67°F Showers And Thunderstorms Likely 0 to 5 mph SSW 83%
Sunday 74°F Showers And Thunderstorms Likely 5 to 15 mph N 70%
Sunday Night 58°F Chance Showers And Thunderstorms 10 to 15 mph NE 47%
Monday 67°F Rain Showers Likely 10 to 15 mph ENE 56%
Monday Night 53°F Chance Rain Showers 10 to 15 mph NE 46%
Tuesday 66°F Slight Chance Rain Showers 10 to 15 mph NE 23%
Tuesday Night 53°F Slight Chance Rain Showers then Mostly Cloudy 5 to 10 mph NE 17%
Wednesday 69°F Mostly Sunny 5 to 10 mph NNE 8%
Wednesday Night 54°F Mostly Cloudy 0 to 5 mph NNE 1%
Thursday 71°F Partly Sunny 5 mph NNE 3%
Thursday Night 55°F Partly Cloudy 0 to 5 mph NNE 3%
Friday 74°F Mostly Sunny 0 to 5 mph NE 3%
Friday Night 54°F Partly Cloudy 0 to 5 mph ENE 3%

Forecast source: National Weather Service (api.weather.gov) for South Wilmington (41.174, -88.279). Updated through the day.

Growing snapshot for South Wilmington

Last spring frost
Apr 27
First fall frost
Oct 15
Growing season
170 days
Hardiness zone
5b

More local growing data for South Wilmington: nearby ZIP 60474 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, Dwight, Il (8.9 mi from South Wilmington). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.