Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78° N Lon: 89.25° W Elev: 400 ft.

Overcast

45°F

7°C

Humidity 63%
Wind Speed SE 5 mph
Barometer 30.35 in (1027.9 mb)
Dewpoint 33°F (1°C)
Visibility 10.00 mi
Wind Chill42°F (6°C)
Last update 29 Mar 12:52 am CDT
Detailed forecast for

Union County

Overnight
Partly cloudy. Near steady temperature in the lower 40s. Southeast winds around 5 mph.
Sunday
Mostly sunny. Highs around 70. South winds 10 to 15 mph with gusts up to 25 mph.
Sunday Night
Partly cloudy in the evening, then clearing. Not as cool with lows in the mid 50s. South winds around 10 mph.
Monday
Mostly sunny. Highs in the upper 70s. South winds 15 to 20 mph with gusts up to 30 mph.
Monday Night
Mostly clear. Lows in the mid 60s. South winds around 15 mph with gusts up to 30 mph.
Tuesday
Mostly sunny. Highs in the lower 80s.
Tuesday Night
Partly cloudy in the evening, then mostly cloudy with showers likely after midnight. Lows in the upper 50s. Chance of rain 60 percent.
Wednesday
A chance of thunderstorms. Showers. Highs in the upper 60s. Chance of rain 80 percent.
Wednesday Night And Thursday
Showers likely with a chance of thunderstorms. Lows in the mid 50s. Highs in the upper 60s. Chance of rain 70 percent.
Thursday Night
Showers likely. Lows in the lower 50s. Chance of rain 70 percent.
Friday
Mostly cloudy with a 50 percent chance of showers. Highs in the mid 70s.
Friday Night
Mostly cloudy with a chance of showers. Lows in the upper 50s. Chance of rain 50 percent.
Saturday
Showers likely. Highs in the lower 70s. Chance of rain 60 percent.



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1214 AM CDT Sun Mar 29 2026
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database