| NWS Forecast for: Jefferson County Issued by: National Weather Service Saint Louis, MO Last Update: 1127 AM CDT Tue Oct 13 2026 | |
| This Afternoon: Sunny. Highs in the lower 90s. Southwest winds 5 to 10 mph. Heat index values up to 100. Tonight: Mostly clear in the evening, then partly cloudy with showers likely with a chance of thunderstorms after midnight. Lows in the lower 70s. South winds 5 to 10 mph, becoming southwest after midnight. Chance of rain 70 percent. Wednesday: A chance of thunderstorms. Showers. Patchy fog. Much cooler. Humid with highs in the upper 70s. Northwest winds around 5 mph. Chance of rain 90 percent. Wednesday Night: Mostly cloudy. A chance of showers and thunderstorms in the evening, then showers likely with a slight chance of thunderstorms after midnight. Lows in the upper 60s. East winds around 5 mph. Chance of rain 70 percent. Thursday: A chance of thunderstorms. Showers. Highs in the mid 80s. South winds around 5 mph, becoming southwest in the afternoon. Chance of rain 90 percent. Thursday Night: A chance of thunderstorms in the evening. Mostly cloudy with a chance of showers. Much cooler with lows in the upper 40s. Chance of rain 50 percent. Friday: Mostly sunny. Much cooler with highs in the lower 60s. Friday Night Through Saturday Night: Mostly clear. Lows in the upper 30s. Highs in the lower 60s. Sunday: Sunny. Highs in the lower 70s. Sunday Night And Monday: Partly cloudy. Lows in the mid 40s. Highs in the mid 70s. | |
| Zone Forecast: Jefferson County | |
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