Current conditions at

Southern Illinois Airport (KMDH)

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

Fair

33°F

1°C

Humidity 54%
Wind Speed NW 10 mph
Barometer 30.29 in (1026.1 mb)
Dewpoint 18°F (-8°C)
Visibility 10.00 mi
Wind Chill25°F (-4°C)
Last update 11 Jan 2:52 am CST
Detailed forecast for

Union County

Overnight
Partly cloudy. Cooler with lows in the upper 20s. Northwest winds 10 to 15 mph with gusts up to 30 mph.
Sunday
Sunny. Highs around 40. Northwest winds 10 to 15 mph. Gusts up to 30 mph in the morning.
Sunday Night
Mostly clear. Lows in the mid 20s. Calm winds, becoming southwest around 5 mph after midnight.
Monday
Sunny. Highs around 50. Southwest winds 5 to 10 mph.
Monday Night
Mostly clear. Lows in the mid 30s. Southwest winds 5 to 10 mph.
Tuesday
Mostly sunny. Highs in the upper 50s.
Tuesday Night And Wednesday
Mostly cloudy. Lows in the lower 40s. Highs in the mid 40s.
Wednesday Night
Mostly cloudy in the evening, then becoming partly cloudy. Much cooler with lows around 20.
Thursday And Thursday Night
Partly cloudy. Highs in the upper 30s. Lows in the upper 20s.
Friday
Partly sunny. Highs in the mid 40s.
Friday Night
Mostly cloudy in the evening, then becoming partly cloudy. Lows in the mid 20s.
Saturday
Partly sunny. Highs in the mid 30s.



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143 AM CST Sun Jan 11 2026
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database