Eureka, IL Weather & Growing Conditions
Tonight
53°F
Rain then Rain Showers
Rain and a slight chance of thunderstorms before midnight, then rain showers. Mostly cloudy. Low around 53, with temperatures rising to around 59 overnight. South wind 14 to 17 mph, with gusts as high as 28 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 53°F | Rain then Rain Showers | 14 to 17 mph S | 96% |
| Wednesday | 59°F | Slight Chance Light Rain then Mostly Cloudy | 16 mph SW | 23% |
| Wednesday Night | 45°F | Mostly Cloudy | 13 mph SW | 5% |
| Thursday | 58°F | Partly Sunny | 9 to 15 mph WSW | 9% |
| Thursday Night | 42°F | Mostly Cloudy then Chance Light Rain | 5 to 8 mph NW | 31% |
| Friday | 54°F | Slight Chance Light Rain | 8 to 12 mph N | 19% |
| Friday Night | 35°F | Partly Cloudy | 2 to 9 mph NNW | 4% |
| Saturday | 53°F | Mostly Sunny | 2 to 6 mph WNW | 3% |
| Saturday Night | 34°F | Partly Cloudy | 3 mph WSW | 3% |
| Sunday | 59°F | Sunny | 3 to 9 mph W | 14% |
| Sunday Night | 35°F | Mostly Clear | 3 to 7 mph W | 5% |
| Monday | 63°F | Sunny | 3 to 12 mph SW | 3% |
| Monday Night | 39°F | Mostly Clear | 5 to 8 mph WSW | 2% |
| Tuesday | 65°F | Sunny | 7 mph WNW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Eureka, IL
Last spring frost
Apr 21
First fall frost
Oct 17
Growing season
178 days
Hardiness zone
5b
Explore more for Eureka, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Congerville 2Nw, Il (6.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.