| NWS Forecast for: Washington County Issued by: National Weather Service Saint Louis, MO Last Update: 728 AM CDT Mon May 18 2026 |  |
Today: Showers with a chance of thunderstorms this morning, then showers with thunderstorms likely this afternoon. Some thunderstorms may produce heavy rainfall. Locally heavy rainfall possible this afternoon. Highs in the upper 70s. South winds 10 to 15 mph with gusts up to 30 mph. Chance of rain near 100 percent. Tonight: Mostly cloudy. A chance of showers and thunderstorms in the evening, then a chance of thunderstorms with a slight chance of showers after midnight. Some thunderstorms may produce heavy rainfall in the evening. Lows in the upper 60s. South winds 10 to 15 mph with gusts up to 30 mph. Chance of rain 50 percent. Tuesday: Showers likely with a chance of thunderstorms in the morning, then showers with thunderstorms likely in the afternoon. Highs in the mid 80s. Temperature falling into the upper 70s in the afternoon. Southwest winds 10 to 15 mph with gusts up to 25 mph. Chance of rain near 100 percent. Tuesday Night: Showers with a chance of thunderstorms in the evening, then showers likely after midnight. Much cooler with lows in the mid 50s. North winds around 5 mph. Chance of rain near 100 percent. Wednesday: Mostly cloudy. A chance of showers, mainly in the morning. Much cooler with highs in the upper 60s. Northeast winds 5 to 10 mph. Chance of rain 50 percent. Wednesday Night: Mostly cloudy. Lows around 50. Thursday: Partly sunny. A slight chance of showers in the afternoon. Highs in the lower 70s. Chance of rain 20 percent. Thursday Night: Mostly cloudy. A slight chance of showers in the evening, then a chance of showers after midnight. Lows in the mid 50s. Chance of rain 40 percent. Friday: Mostly cloudy. A chance of showers in the morning, then showers likely with a chance of thunderstorms in the afternoon. Highs in the upper 70s. Chance of rain 60 percent. Friday Night: Mostly cloudy with a chance of showers with a slight chance of thunderstorms. Lows in the upper 50s. Chance of rain 50 percent. Saturday: Partly sunny. A slight chance of showers and thunderstorms in the afternoon. Highs in the lower 80s. Chance of rain 20 percent. Saturday Night: Partly cloudy. Lows in the upper 50s. Sunday: Mostly sunny. A slight chance of showers and thunderstorms in the afternoon. Highs in the mid 80s. Chance of rain 20 percent. | |
| Zone Forecast: Washington County | |
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