7-Day Zone Forecast for St. Clair County (Text-Only)
NWS Forecast for: St. Clair County
Issued by: National Weather Service Saint Louis, MO
Last Update: 538 AM CDT Sat Jul 25 2026




Today: Partly sunny. Showers with a slight chance of thunderstorms this morning. Warmer with highs in the upper 80s. South winds around 5 mph. Chance of rain 80 percent. Heat index values up to 100 this afternoon.

Tonight: Partly cloudy in the evening, then becoming mostly clear. Humid with lows in the lower 70s. Southeast winds around 5 mph in the evening, becoming light and variable. Heat index values up to 101 early in the evening.

Sunday: Mostly sunny. Humid with highs in the mid 90s. South winds around 5 mph. Heat index values up to 110.

Sunday Night: Partly cloudy. Humid with lows in the mid 70s. South winds around 5 mph. Heat index values up to 109 early in the evening.

Monday: Sunny, hot with highs in the upper 90s. Southwest winds 5 to 10 mph. Heat index values up to 112.

Monday Night And Tuesday: Mostly clear. Lows in the upper 70s. Highs in the lower 90s. Heat index values up to 110.

Tuesday Night: Partly cloudy. Lows in the lower 70s. Heat index values up to 100 early in the evening.

Wednesday And Wednesday Night: Mostly clear. Highs in the lower 90s. Lows in the lower 70s.

Thursday: Mostly sunny. Highs in the lower 90s.

Thursday Night And Friday: Partly cloudy. A slight chance of showers and thunderstorms. Lows in the lower 70s. Highs around 90. Chance of rain 20 percent.







Zone Forecast: St. Clair County

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