Current conditions at

Southern Illinois Airport (KMDH)

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

Light Rain

72°F

22°C

Humidity 94%
Wind Speed SE 6 mph
Barometer 30.06 in
Dewpoint 70°F (21°C)
Visibility 7.00 mi
Last update 25 Jul 8:52 am CDT
Detailed forecast for

Union County

Today
Partly sunny. A chance of showers and thunderstorms this morning. Highs in the mid 80s. South winds around 5 mph. Chance of rain 50 percent.
Tonight
Partly cloudy in the evening, then becoming mostly cloudy. Humid with lows in the lower 70s. Calm winds.
Sunday
Partly sunny in the morning, then clearing. Humid with highs in the lower 90s. Calm winds.
Sunday Night
Mostly clear in the evening, then becoming partly cloudy. Humid with lows in the mid 70s. Calm winds, becoming south around 5 mph after midnight.
Monday
Sunny, hot with highs in the mid 90s. Southwest winds 5 to 10 mph. Highest heat index readings heat index readings up to 108 in the afternoon.
Monday Night And Tuesday
Mostly clear. Hot. Lows in the upper 70s. Highs in the mid 90s.
Tuesday Night
Mostly clear in the evening, then becoming partly cloudy. Lows in the lower 70s.
Wednesday And Wednesday Night
Mostly clear. Highs in the lower 90s. Lows around 70.
Thursday Through Friday
Partly cloudy. Highs in the lower 90s. Lows in the lower 70s.



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837 AM CDT Sat Jul 25 2026
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database