St. Elmo, IL Weather & Growing Conditions
Tonight
71°F
Partly Cloudy
Partly cloudy, with a low around 71. South wind 1 to 5 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 71°F | Partly Cloudy | 1 to 5 mph S | 6% |
| Sunday | 92°F | Mostly Sunny then Chance Showers And Thunderstorms | 3 to 8 mph W | 27% |
| Sunday Night | 63°F | Chance Showers And Thunderstorms | 5 to 9 mph NE | 71% |
| Monday | 78°F | Showers And Thunderstorms Likely | 9 mph NE | 71% |
| Monday Night | 57°F | Chance Showers And Thunderstorms | 6 to 10 mph NE | 40% |
| Tuesday | 71°F | Chance Rain Showers | 10 mph NE | 25% |
| Tuesday Night | 54°F | Mostly Cloudy | 5 to 10 mph N | 5% |
| Wednesday | 72°F | Partly Sunny | 6 to 9 mph N | 3% |
| Wednesday Night | 54°F | Partly Cloudy | 2 to 9 mph N | 1% |
| Thursday | 75°F | Mostly Sunny | 3 to 7 mph N | 0% |
| Thursday Night | 56°F | Mostly Cloudy | 2 to 7 mph N | 7% |
| Friday | 78°F | Partly Sunny then Slight Chance Rain Showers | 3 to 7 mph NE | 15% |
| Friday Night | 55°F | Slight Chance Rain Showers then Partly Cloudy | 2 to 7 mph NE | 15% |
| Saturday | 80°F | Mostly Sunny | 5 mph NE | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Elmo, IL
Last spring frost
Apr 3
First fall frost
Oct 24
Growing season
202 days
Hardiness zone
6b
Explore more for St. Elmo, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Brownstown 4 Sw, Il (7.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.