Simpson, IL Weather & Growing Conditions
Today
88°F
Sunny
Sunny. High near 88, with temperatures falling to around 86 in the afternoon. East northeast wind around 3 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 88°F | Sunny | 3 mph ENE | 0% |
| Tonight | 64°F | Mostly Clear | 3 mph ENE | 0% |
| Wednesday | 90°F | Patchy Fog then Sunny | 3 mph S | 0% |
| Wednesday Night | 69°F | Mostly Clear | 2 mph SSE | 0% |
| Thursday | 89°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 5 mph SW | 15% |
| Thursday Night | 71°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 2 mph SSW | 34% |
| Friday | 88°F | Chance Showers And Thunderstorms | 0 to 6 mph SW | 48% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 0 to 3 mph SW | 49% |
| Saturday | 89°F | Chance Showers And Thunderstorms | 1 to 5 mph SW | 49% |
| Saturday Night | 71°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 2 mph SSW | 15% |
| Sunday | 91°F | Sunny | 0 to 7 mph SSW | 8% |
| Sunday Night | 73°F | Mostly Clear | 5 mph SSW | 6% |
| Monday | 93°F | Sunny | 3 to 9 mph SSW | 6% |
| Monday Night | 74°F | Mostly Clear | 7 mph SSW | 6% |
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 Aug 4, 2026.