Current conditions at

Southern Illinois Airport (KMDH)

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

Partly Cloudy

69°F

21°C

Humidity 87%
Wind Speed Calm
Barometer 29.94 in (1013.3 mb)
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Last update 20 Jun 11:52 pm CDT
Detailed forecast for

Union County

Tonight
Mostly clear. Lows in the mid 60s. Southeast winds around 5 mph.
Sunday
Mostly sunny in the morning, then becoming mostly cloudy. A chance of showers and thunderstorms. Highs in the upper 80s. South winds 10 to 15 mph. Gusts up to 30 mph in the afternoon. Chance of rain 50 percent.
Sunday Night
Thunderstorms likely. Showers. Lows in the lower 70s. Southwest winds 10 to 15 mph. Gusts up to 30 mph in the evening. Chance of rain 90 percent.
Monday
Becoming partly sunny in the afternoon. A chance of thunderstorms. Showers likely, mainly in the morning. Highs in the lower 80s. West winds 5 to 10 mph. Chance of rain 70 percent.
Monday Night
Partly cloudy. Lows in the lower 60s. North winds 5 to 10 mph.
Tuesday
Mostly sunny. Highs in the lower 80s.
Tuesday Night
Partly cloudy in the evening, then becoming mostly clear. Lows in the mid 60s.
Wednesday Through Thursday Night
Partly cloudy. Highs in the mid 80s. Lows in the mid 60s.
Friday
Mostly sunny. A chance of showers and thunderstorms in the afternoon. Highs in the mid 80s. Chance of rain 40 percent.
Friday Night
Partly cloudy in the evening, then becoming mostly cloudy. A chance of thunderstorms in the evening. A chance of showers. Lows in the upper 60s. Chance of rain 40 percent.
Saturday
Partly sunny with a chance of showers. A chance of thunderstorms in the afternoon. Highs in the mid 80s. Chance of rain 50 percent.



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1147 PM CDT Sat Jun 20 2026
 
 

Additional Resources

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