| NWS Forecast for: St. Clair County Issued by: National Weather Service Saint Louis, MO Last Update: 228 AM CDT Sat Jun 27 2026 | |
Rest Of Tonight: Mostly cloudy with a slight chance of showers and thunderstorms. Patchy fog. Near steady temperature in the lower 70s. Light and variable winds. Chance of rain 20 percent. Saturday: Mostly cloudy in the morning, then becoming partly sunny. A slight chance of thunderstorms. A chance of showers, mainly in the morning. Humid with highs in the mid 80s. Southwest winds around 5 mph. Chance of rain 40 percent. Saturday Night: Mostly clear in the evening, then becoming mostly cloudy. A chance of showers and thunderstorms. Humid with lows in the lower 70s. Southeast winds around 5 mph. Chance of rain 40 percent. Sunday: Sunny with highs in the mid 90s. South winds 5 to 10 mph. Heat index values up to 111 in the afternoon. Sunday Night: Mostly clear. Humid with lows in the mid 70s. South winds 5 to 10 mph. Heat index values up to 111 early in the evening. Monday And Monday Night: Mostly clear. Hot. Highs in the mid 90s. Lows in the mid 70s. Heat index values up to 115. Tuesday Through Wednesday: Clear, hot. Highs in the upper 90s. Lows in the mid 70s. Heat index values up to 110. Wednesday Night Through Thursday Night: Mostly clear. Hot. Lows in the upper 70s. Highs in the mid 90s. Heat index values up to 110. Friday: Mostly sunny with a slight chance of showers and thunderstorms. Highs in the mid 90s. Chance of rain 20 percent. Heat index values up to 105. | |
| Zone Forecast: St. Clair County | |
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