| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 902 PM CDT Sat Sep 5 2026 | |
| Tonight: Partly cloudy. A slight chance of showers and thunderstorms this evening. Lows in the lower 70s. Northeast winds around 5 mph. Gusts up to 20 mph after midnight. Chance of rain 20 percent. Heat index values up to 104 early this evening. Sunday: Mostly sunny. Highs in the lower 90s. Northeast winds 5 to 10 mph. Sunday Night: Mostly clear. Lows in the mid 60s. Northeast winds 5 to 10 mph. Labor Day: Sunny. Highs around 90. East winds around 5 mph. Monday Night: Mostly clear. Lows in the mid 60s. East winds around 5 mph. Tuesday Through Wednesday: Mostly clear. Hot. Highs in the upper 90s. Lows in the lower 70s. Heat index values up to 105. Wednesday Night: Partly cloudy. A slight chance of showers and thunderstorms in the evening, then a chance of showers and thunderstorms after midnight. Lows in the lower 70s. Chance of rain 50 percent. Heat index values up to 100 early in the evening. Thursday: Partly sunny. A chance of showers with a slight chance of thunderstorms in the morning. Not as warm with highs in the mid 80s. Chance of rain 50 percent. Thursday Night: Partly cloudy. A slight chance of showers and thunderstorms after midnight. Lows in the mid 60s. Chance of rain 20 percent. Friday: Mostly sunny. A slight chance of showers in the morning. Highs in the upper 80s. Chance of rain 20 percent. Friday Night: Partly cloudy. A chance of showers after midnight. Lows in the mid 60s. Chance of rain 30 percent. Saturday: Mostly sunny. A slight chance of showers in the morning. Highs in the lower 90s. Chance of rain 20 percent. | |
| Zone Forecast: St. Clair County | |
Visit your local NWS office at: https://www.weather.gov/lsx/ |