Simpson, IL Weather & Growing Conditions
Overnight
57°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms before 5am. Mostly cloudy. Low around 57, with temperatures rising to around 59 overnight. South southwest wind around 6 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 57°F | Slight Chance Showers And Thunderstorms | 6 mph SSW | 22% |
| Wednesday | 67°F | Partly Sunny | 5 to 9 mph WSW | 8% |
| Wednesday Night | 44°F | Mostly Clear | 0 to 3 mph WSW | 0% |
| Thursday | 69°F | Sunny | 1 to 7 mph SW | 0% |
| Thursday Night | 45°F | Partly Cloudy | 1 mph WNW | 0% |
| Friday | 62°F | Partly Sunny | 1 to 8 mph NNW | 0% |
| Friday Night | 37°F | Partly Cloudy | 1 to 6 mph N | 0% |
| Saturday | 58°F | Mostly Sunny | 1 to 6 mph N | 0% |
| Saturday Night | 33°F | Partly Cloudy | 1 mph NNW | 0% |
| Sunday | 61°F | Sunny | 0 to 5 mph NNW | 0% |
| Sunday Night | 34°F | Clear | 1 mph NNW | 0% |
| Monday | 65°F | Sunny | 0 to 5 mph WSW | 0% |
| Monday Night | 38°F | Clear | 1 mph WSW | 1% |
| Tuesday | 69°F | Sunny | 0 to 5 mph WSW | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Simpson, IL
Last spring frost
Apr 14
First fall frost
Oct 21
Growing season
189 days
Hardiness zone
7a
Explore more for Simpson, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Dixon Springs Agric Ctr, Il (2.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.