Fairfield, IL Weather & Growing Conditions
Tonight
70°F
Slight Chance Showers And Thunderstorms then Partly Cloudy
A slight chance of showers and thunderstorms before 10pm. Partly cloudy. Low around 70, with temperatures rising to around 72 overnight. East southeast wind around 3 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 70°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 3 mph ESE | 22% |
| Saturday | 97°F | Sunny | 2 to 7 mph SW | 11% |
| Saturday Night | 72°F | Partly Cloudy | 1 to 5 mph SSW | 8% |
| Sunday | 96°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 2 to 7 mph W | 17% |
| Sunday Night | 67°F | Chance Showers And Thunderstorms | 6 mph NNE | 30% |
| Monday | 85°F | Chance Rain Showers then Chance Showers And Thunderstorms | 5 to 10 mph NNE | 50% |
| Monday Night | 61°F | Chance Showers And Thunderstorms | 6 to 13 mph NNE | 50% |
| Tuesday | 75°F | Chance Showers And Thunderstorms | 9 to 13 mph NNE | 39% |
| Tuesday Night | 56°F | Mostly Cloudy | 5 to 13 mph NNE | 8% |
| Wednesday | 75°F | Mostly Sunny | 6 to 10 mph N | 3% |
| Wednesday Night | 56°F | Partly Cloudy | 2 to 9 mph NNE | 3% |
| Thursday | 77°F | Mostly Sunny | 2 to 9 mph N | 3% |
| Thursday Night | 57°F | Partly Cloudy | 2 to 8 mph NNE | 3% |
| Friday | 77°F | Mostly Sunny | 3 to 8 mph NNE | 4% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Fairfield, IL
Last spring frost
Apr 7
First fall frost
Oct 26
Growing season
201 days
Hardiness zone
6b
Explore more for Fairfield, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Fairfield Radio Wfiw, Il (2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.