Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89° N Lon: 90.03° W Elev: 518 ft.

Partly Cloudy

88°F

31°C

Humidity 55%
Wind Speed N 9 mph
Barometer 29.84 in
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index93°F (34°C)
Last update 21 Jul 2:50 pm CDT
Detailed forecast for

Macoupin County

Tonight
Mostly clear. Cooler with lows in the mid 60s. North winds 10 to 15 mph.
Wednesday
Mostly sunny. Cooler with highs around 80. North winds 5 to 10 mph.
Wednesday Night
Partly cloudy in the evening, then clearing. Lows in the upper 50s. Northeast winds 5 to 10 mph.
Thursday
Sunny. Highs around 80. East winds around 5 mph.
Thursday Night
Partly cloudy. Lows in the upper 50s. East winds around 5 mph.
Friday
Partly sunny in the morning, then becoming mostly cloudy. A chance of showers and thunderstorms. Highs in the upper 70s. Chance of rain 50 percent.
Friday Night
Mostly cloudy with a slight chance of showers and thunderstorms. Lows in the lower 60s. Chance of rain 20 percent.
Saturday
Mostly sunny. Highs in the upper 80s.
Saturday Night And Sunday
Mostly clear. Lows in the upper 60s. Highs in the mid 90s. Heat index values up to 105.
Sunday Night And Monday
Mostly clear. Hot. Lows in the mid 70s. Highs in the upper 90s. Heat index values up to 105.
Monday Night
Mostly clear with a slight chance of showers and thunderstorms. Lows around 70. Chance of rain 20 percent. Heat index values up to 105 early in the evening.
Tuesday
Sunny. Highs in the lower 90s.



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253 PM CDT Tue Jul 21 2026
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database