Grafton, IL Weather & Growing Conditions
Tonight
55°F
Light Rain Likely
Rain likely before 3am, then a slight chance of drizzle. Cloudy, with a low around 55. Southwest wind 9 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 55°F | Light Rain Likely | 9 to 14 mph SW | 71% |
| Wednesday | 61°F | Slight Chance Drizzle then Mostly Cloudy | 10 to 15 mph W | 12% |
| Wednesday Night | 46°F | Partly Cloudy | 9 mph SW | 0% |
| Thursday | 64°F | Sunny | 8 to 13 mph W | 4% |
| Thursday Night | 46°F | Slight Chance T-storms then Mostly Cloudy | 8 mph NW | 15% |
| Friday | 57°F | Mostly Cloudy | 8 to 12 mph NW | 6% |
| Friday Night | 41°F | Partly Cloudy | 3 to 8 mph N | 1% |
| Saturday | 56°F | Mostly Sunny | 5 mph NW | 0% |
| Saturday Night | 39°F | Partly Cloudy | 3 mph W | 1% |
| Sunday | 62°F | Sunny | 3 to 8 mph W | 8% |
| Sunday Night | 40°F | Mostly Clear | 6 mph W | 4% |
| Monday | 65°F | Sunny | 5 to 9 mph SW | 2% |
| Monday Night | 44°F | Mostly Clear | 6 mph SW | 1% |
| Tuesday | 68°F | Sunny | 7 mph W | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Grafton, IL
Last spring frost
Apr 5
First fall frost
Oct 27
Growing season
203 days
Hardiness zone
6b
Explore more for Grafton, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, St Charles Co Ap, Mo (6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.