South Wilmington, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for South Wilmington, a village in Grundy County, Illinois.
This Afternoon
73°F
Chance Rain
A chance of rain. Mostly cloudy. High near 73, with temperatures falling to around 69 in the afternoon. South wind 15 to 20 mph, with gusts as high as 35 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for South Wilmington
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 73°F | Chance Rain | 15 to 20 mph S | 42% |
| Tonight | 59°F | Rain | 15 mph S | 84% |
| Wednesday | 64°F | Chance Rain then Mostly Cloudy | 15 mph SSW | 44% |
| Wednesday Night | 47°F | Mostly Cloudy | 10 mph SW | 7% |
| Thursday | 60°F | Mostly Cloudy | 10 to 15 mph WSW | 11% |
| Thursday Night | 42°F | Chance Rain | 5 mph WNW | 32% |
| Friday | 56°F | Slight Chance Rain | 5 to 10 mph NNW | 21% |
| Friday Night | 35°F | Partly Cloudy | 0 to 5 mph NNW | 6% |
| Saturday | 54°F | Mostly Sunny | 0 to 5 mph WNW | 6% |
| Saturday Night | 33°F | Partly Cloudy | 0 mph | 3% |
| Sunday | 59°F | Mostly Sunny | 0 to 5 mph W | 10% |
| Sunday Night | 33°F | Mostly Clear | 0 to 5 mph WNW | 9% |
| Monday | 64°F | Sunny | 0 to 10 mph WSW | 4% |
| Monday Night | 38°F | Mostly Clear | 5 mph WSW | 2% |
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
Nearby towns & communities
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 Nov 3, 2026.