| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 254 PM CDT Sat Aug 8 2026 | |
Tonight: Clear. Lows in the lower 70s. South winds around 5 mph. Sunday: Sunny with highs in the lower 90s. South winds 10 to 15 mph. Heat index values up to 104. Sunday Night: Mostly clear. Humid with lows in the mid 70s. South winds 5 to 10 mph. Heat index values up to 103 early in the evening. Monday: Mostly sunny. Hot with highs in the mid 90s. Southwest winds 5 to 10 mph. Heat index values up to 111 in the afternoon. Monday Night: Mostly clear. Humid with lows in the upper 70s. South winds 5 to 10 mph. Heat index values up to 109 early in the evening. Tuesday: Mostly sunny. Hot with highs in the mid 90s. Heat index values up to 110. Tuesday Night: Partly cloudy. A slight chance of showers and thunderstorms after midnight. Lows in the upper 70s. Chance of rain 20 percent. Heat index values up to 105 early in the evening. Wednesday: Partly sunny. A slight chance of showers and thunderstorms in the morning, then a chance of showers and thunderstorms in the afternoon. Highs in the lower 90s. Chance of rain 40 percent. Heat index values up to 105. Wednesday Night: Partly cloudy in the evening, then becoming mostly cloudy. A chance of showers and thunderstorms. Lows in the lower 70s. Chance of rain 50 percent. Heat index values up to 105 early in the evening. Thursday And Thursday Night: Showers and thunderstorms likely. Highs in the mid 80s. Lows around 70. Chance of rain 60 percent. Friday Through Saturday: Mostly cloudy with a chance of showers and thunderstorms. Highs in the mid 80s. Lows in the upper 60s. Chance of rain 50 percent. | |
| Zone Forecast: St. Clair County | |
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