Lewistown, IL Weather & Growing Conditions
Today
89°F
Mostly Sunny
Mostly sunny, with a high near 89. South wind 2 to 6 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 89°F | Mostly Sunny | 2 to 6 mph S | 0% |
| Tonight | 68°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 5 mph SSE | 15% |
| Wednesday | 86°F | Chance Showers And Thunderstorms | 2 to 6 mph SSW | 43% |
| Wednesday Night | 66°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 5 mph N | 88% |
| Thursday | 82°F | Showers And Thunderstorms | 2 mph S | 80% |
| Thursday Night | 64°F | Partly Cloudy | 1 mph SE | 12% |
| Friday | 84°F | Mostly Sunny | 0 mph | 6% |
| Friday Night | 66°F | Slight Chance Showers And Thunderstorms | 0 mph | 17% |
| Saturday | 87°F | Slight Chance Showers And Thunderstorms then Sunny | 0 to 3 mph SSW | 16% |
| Saturday Night | 70°F | Mostly Clear | 3 mph S | 9% |
| Sunday | 89°F | Sunny | 5 to 9 mph SSW | 5% |
| Sunday Night | 71°F | Mostly Clear then Slight Chance Showers And Thunderstorms | 3 to 7 mph SSW | 17% |
| Monday | 90°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 5 to 8 mph SSW | 17% |
| Monday Night | 71°F | Slight Chance Showers And Thunderstorms | 7 mph SW | 28% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Lewistown, IL
Last spring frost
Apr 17
First fall frost
Oct 19
Growing season
185 days
Hardiness zone
6a
Explore more for Lewistown, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Havana, Il (6.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.