| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 417 AM CDT Sat Sep 5 2026 | |
Today: Mostly sunny. Isolated showers and thunderstorms this afternoon. Hot with highs around 100. Northwest winds around 5 mph. Chance of rain 20 percent. Heat index values up to 110. Tonight: Partly cloudy with isolated showers in the evening, then mostly clear after midnight. Humid with lows in the lower 70s. Northeast winds around 5 mph. Chance of rain 20 percent. Heat index values up to 106 early in the evening. Sunday: Mostly sunny. Highs in the lower 90s. Northeast winds 5 to 10 mph. Sunday Night: Mostly clear. Lows in the mid 60s. East winds 5 to 10 mph. Labor Day: Sunny. Highs in the upper 80s. East winds around 5 mph. Monday Night And Tuesday: Mostly clear. Hot. Lows in the mid 60s. Highs in the mid 90s. Tuesday Night And Wednesday: Mostly clear. Hot. Lows in the mid 70s. Highs in the upper 90s. Heat index values up to 105. Wednesday Night: Mostly clear in the evening, then becoming partly cloudy. A slight chance of thunderstorms. A slight chance of showers in the evening, then a chance of showers after midnight. Lows in the lower 70s. Chance of rain 50 percent. Heat index values up to 100 early in the evening. Thursday: Mostly sunny with a slight chance of thunderstorms. A chance of showers, mainly in the morning. Highs around 90. Chance of rain 50 percent. Thursday Night: Partly cloudy in the evening, then mostly clear with a slight chance of showers and thunderstorms after midnight. Lows in the mid 60s. Chance of rain 20 percent. Friday: Mostly sunny with a slight chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the upper 80s. Chance of rain 20 percent. | |
| Zone Forecast: St. Clair County | |
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