| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 1027 AM CDT Mon Aug 31 2026 |  |
Rest Of Today: Sunny, hot with highs in the upper 90s. Southwest winds 5 to 10 mph. Tonight: Clear. Lows in the mid 70s. South winds 5 to 10 mph. Heat index values up to 100 early in the evening. Tuesday: Sunny, hot with highs in the upper 90s. Southwest winds around 5 mph. Tuesday Night: Mostly clear. Lows in the upper 70s. South winds around 5 mph. Heat index values up to 102 early in the evening. Wednesday: Sunny, hot with highs in the upper 90s. Southwest winds 5 to 10 mph. Wednesday Night Through Thursday Night: Mostly clear. Hot. Lows in the upper 70s. Highs in the upper 90s. Heat index values up to 105. Friday: Sunny. A slight chance of showers and thunderstorms in the afternoon. Highs in the mid 90s. Chance of rain 20 percent. Heat index values up to 100. Friday Night: Mostly clear. Lows in the mid 70s. Saturday: Sunny with a slight chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the lower 90s. Chance of rain 20 percent. Saturday Night And Sunday: Mostly clear. Lows in the lower 70s. Highs in the lower 90s. | |
| Zone Forecast: St. Clair County | |
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