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: 127 AM CDT Sun Jul 26 2026




Rest Of Tonight: Mostly cloudy. Near steady temperature in the mid 70s. Light and variable winds.

Sunday: Mostly cloudy with a slight chance of showers and thunderstorms in the morning, then mostly sunny in the afternoon. Hot with highs in the mid 90s. Southwest winds around 5 mph. Chance of rain 20 percent. Heat index values up to 117.

Sunday Night: Partly cloudy. Humid with lows in the upper 70s. South winds around 5 mph. Heat index values up to 116 early in the evening.

Monday: Sunny, hot with highs in the upper 90s. Southwest winds 5 to 10 mph. Heat index values up to 114.

Monday Night: Mostly clear. Humid with lows in the upper 70s. Southwest winds 5 to 10 mph. Heat index values up to 112 early in the evening.

Tuesday And Tuesday Night: Partly cloudy. Highs in the lower 90s. Lows in the lower 70s. Heat index values up to 105.

Wednesday Through Thursday: Mostly clear. Highs in the upper 80s. Lows in the upper 60s.

Thursday Night: Partly cloudy in the evening, then mostly cloudy with a slight chance of showers after midnight. Lows in the upper 60s. Chance of rain 20 percent.

Friday: Partly sunny with a slight chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the mid 80s. Chance of rain 20 percent.

Friday Night: A slight chance of thunderstorms in the evening. Partly cloudy with a chance of showers. Lows in the upper 60s. Chance of rain 40 percent.

Saturday: Mostly sunny with a slight chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the mid 80s. Chance of rain 20 percent.







Zone Forecast: St. Clair County

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