Thornton, IL Weather & Growing Conditions
This Afternoon
75°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 5pm, then a slight chance of showers and thunderstorms. Cloudy, with a high near 75. East southeast wind around 5 mph, with gusts as high as 15 mph. Chance of precipitation is 40%. New rainfall amounts between a half and three quarters of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 75°F | Chance Showers And Thunderstorms | 5 mph ESE | 36% |
| Tonight | 65°F | Showers And Thunderstorms | 5 mph S | 94% |
| Sunday | 71°F | Showers And Thunderstorms Likely | 10 to 15 mph NNE | 65% |
| Sunday Night | 56°F | Chance Showers And Thunderstorms | 15 mph NE | 38% |
| Monday | 66°F | Chance Rain Showers | 15 mph NE | 36% |
| Monday Night | 53°F | Slight Chance Rain Showers then Mostly Cloudy | 10 to 15 mph NE | 22% |
| Tuesday | 64°F | Slight Chance Rain Showers | 10 to 15 mph NE | 17% |
| Tuesday Night | 53°F | Mostly Cloudy | 10 to 15 mph NE | 13% |
| Wednesday | 65°F | Partly Sunny | 10 mph NE | 12% |
| Wednesday Night | 54°F | Mostly Cloudy | 5 to 10 mph NNE | 6% |
| Thursday | 67°F | Partly Sunny | 5 to 10 mph NNE | 3% |
| Thursday Night | 54°F | Mostly Cloudy | 5 to 10 mph NNE | 3% |
| Friday | 70°F | Mostly Sunny | 5 to 10 mph NE | 3% |
| Friday Night | 54°F | Partly Cloudy | 0 to 10 mph NE | 3% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Thornton, IL
Last spring frost
Apr 23
First fall frost
Oct 20
Growing season
179 days
Hardiness zone
6a
Explore more for Thornton, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Park Forest, Il (6.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.