Current conditions at

Southern Illinois Airport (KMDH)

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

Fair

54°F

12°C

Humidity 93%
Wind Speed NW 5 mph
Barometer 29.96 in (1014.4 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Wind Chill53°F (12°C)
Last update 11 Oct 3:52 am CDT
Detailed forecast for

Union County

Overnight
Partly cloudy. Near steady temperature in the upper 50s. North winds around 5 mph.
Sunday
Sunny. Highs in the mid 80s. Northwest winds around 5 mph.
Sunday Night
Clear in the evening, then becoming partly cloudy. Lows around 60. South winds around 5 mph.
Columbus Day
Sunny. Highs around 90. Southwest winds 5 to 10 mph.
Monday Night
Clear. Lows in the mid 60s. Southwest winds 5 to 10 mph.
Tuesday
Sunny. Highs in the lower 90s.
Tuesday Night
Mostly clear. Lows in the upper 60s.
Wednesday
Partly sunny with a chance of thunderstorms. A chance of showers in the morning, then showers likely in the afternoon. Highs in the mid 80s. Chance of rain 60 percent.
Wednesday Night And Thursday
Mostly cloudy. A chance of showers. Lows in the mid 60s. Highs in the lower 80s. Chance of rain 50 percent.
Thursday Night
Mostly cloudy with a chance of showers and thunderstorms. Lows in the upper 50s. Chance of rain 50 percent.
Friday
Partly sunny. Highs around 70.
Friday Night
Partly cloudy. Lows in the mid 40s.
Saturday
Sunny. Highs in the lower 60s.



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122 AM CDT Sun Oct 11 2026
 
 

Additional Resources

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