| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 1203 PM CDT Mon Jun 29 2026 |  |
This Afternoon: Mostly sunny. Hot with highs in the mid 90s. South winds 10 to 15 mph. Heat index values up to 110. Tonight: Partly cloudy in the evening, then clearing. Humid with lows in the mid 70s. South winds 10 to 15 mph. Heat index values up to 109 early in the evening. Tuesday: Sunny, hot with highs in the upper 90s. Southwest winds 5 to 10 mph. Heat index values up to 110. Tuesday Night: Clear with lows in the mid 70s. South winds 5 to 10 mph. Heat index values up to 109 early in the evening. Wednesday: Sunny, hot with highs in the upper 90s. South winds 5 to 10 mph. Heat index values up to 109. Wednesday Night Through Thursday Night: Mostly clear. Hot. Lows in the upper 70s. Highs in the upper 90s. Heat index values up to 110. Friday: Sunny with a slight chance of showers and thunderstorms. Hot with highs in the mid 90s. Chance of rain 20 percent. Heat index values up to 110. Friday Night: Partly cloudy in the evening, then becoming mostly clear. Lows in the mid 70s. Heat index values up to 110 early in the evening. Independence Day: Sunny. A slight chance of showers and thunderstorms in the afternoon. Hot with highs in the mid 90s. Chance of rain 20 percent. Heat index values up to 105. Saturday Night: Partly cloudy. A slight chance of showers and thunderstorms after midnight. Lows in the mid 70s. Chance of rain 20 percent. Heat index values up to 105 early in the evening. Sunday: Mostly 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 30 percent. Heat index values up to 100. | |
| Zone Forecast: St. Clair County | |
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