| NWS Forecast for: Jefferson County Issued by: National Weather Service Saint Louis, MO Last Update: 553 AM CDT Fri Jul 31 2026 |  |
| Today: A chance of thunderstorms. Showers. Highs in the mid 80s. South winds 5 to 10 mph. Chance of rain near 100 percent. Tonight: Mostly cloudy. Showers with thunderstorms likely in the evening, then a chance of showers and thunderstorms after midnight. Humid with lows in the upper 60s. South winds 5 to 10 mph, becoming southwest after midnight. Chance of rain 90 percent. Saturday: Mostly cloudy. Showers likely with a slight chance of thunderstorms in the afternoon. Highs in the mid 70s. West winds around 10 mph with gusts up to 25 mph. Chance of rain 60 percent. Saturday Night: Showers likely, mainly in the evening. Lows in the mid 60s. Northwest winds 5 to 10 mph with gusts up to 25 mph. Chance of rain 70 percent. Sunday: Partly sunny with a 40 percent chance of showers. Highs around 80. North winds 5 to 10 mph with gusts up to 20 mph. Sunday Night: Partly cloudy in the evening, then becoming mostly clear. Lows in the mid 60s. Monday: Mostly sunny. A slight chance of showers in the afternoon. Highs in the lower 80s. Chance of rain 20 percent. Monday Night: Mostly clear. Lows in the mid 60s. Tuesday: Sunny. A slight chance of showers in the afternoon. Highs in the upper 80s. Chance of rain 20 percent. Tuesday Night Through Wednesday Night: Mostly clear. Lows in the upper 60s. Highs around 90. Thursday: Mostly sunny. Highs in the lower 90s. Heat index values up to 105. | |
| Zone Forecast: Jefferson County | |
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