Dahlgren, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Dahlgren, a village in Jefferson County, Illinois.
Tonight
57°F
Showers And Thunderstorms
Showers and thunderstorms before 4am. Mostly cloudy. Low around 57, with temperatures rising to around 59 overnight. South wind 9 to 15 mph, with gusts as high as 23 mph. Chance of precipitation is 100%.
7-day forecast for Dahlgren
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 57°F | Showers And Thunderstorms | 9 to 15 mph S | 98% |
| Wednesday | 68°F | Partly Sunny | 7 to 13 mph SW | 12% |
| Wednesday Night | 44°F | Partly Cloudy | 3 mph WSW | 0% |
| Thursday | 69°F | Sunny | 3 to 12 mph WSW | 0% |
| Thursday Night | 44°F | Mostly Cloudy | 2 mph WNW | 5% |
| Friday | 61°F | Mostly Cloudy | 3 to 12 mph NNW | 2% |
| Friday Night | 39°F | Partly Cloudy | 2 to 7 mph NNW | 1% |
| Saturday | 57°F | Mostly Sunny | 2 to 6 mph NNW | 0% |
| Saturday Night | 35°F | Partly Cloudy | 1 mph NW | 1% |
| Sunday | 62°F | Sunny | 1 to 8 mph W | 6% |
| Sunday Night | 34°F | Mostly Clear | 3 mph NW | 5% |
| Monday | 65°F | Sunny | 1 to 9 mph W | 3% |
| Monday Night | 38°F | Mostly Clear | 5 mph SW | 0% |
| Tuesday | 69°F | Sunny | 2 to 7 mph WSW | 1% |
Forecast source: National Weather Service (api.weather.gov) for Dahlgren (38.198, -88.685). Updated through the day.
Growing snapshot for Dahlgren
Last spring frost
Apr 11
First fall frost
Oct 22
Growing season
193 days
Hardiness zone
6b
More local growing data for Dahlgren: nearby ZIP 62810 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Mt Vernon 3 Ne, Il (11.5 mi from Dahlgren). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.