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City of St. Clair, MOSt. Clair, MO 7-Day Night Weather Forecast
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St. Clair, MO Weather Forecast
St. Clair, MO Weather Forecast Date: 127 PM CDT Sun Sep 06 2026
The area/counties/county of: Franklin County Mo, including the cities of: Washington, Union, and Sullivan.or toggle through each period.
This Afternoon... Sunny. Near steady temperature around 90. Northeast winds around 5 mph.
Tonight... Partly cloudy in the evening, then clearing. Cooler with lows in the lower 60s. East winds around 5 mph.
Labor Day... Sunny. Highs in the upper 80s. East winds around 5 mph.
Monday Night... Mostly clear in the evening, then becoming partly cloudy. Lows in the lower 60s. East winds around 5 mph in the evening, becoming light and variable.
Tuesday... Mostly sunny. Highs in the mid 90s. South winds around 5 mph.
Tuesday Night... Mostly clear. Not as cool with lows in the lower 70s.
Wednesday... Sunny. A slight chance of showers and thunderstorms in the afternoon. Hot with highs in the mid 90s. Chance of rain 20%. Heat index values up to 105 in the afternoon.
Wednesday Night... Mostly cloudy with a chance of thunderstorms. Showers. Lows in the upper 60s. Chance of rain 80%. Heat index values up to 100 early in the evening.
Thursday... Mostly cloudy with a chance of showers with a slight chance of thunderstorms in the morning, then partly sunny with a chance of showers and thunderstorms in the afternoon. Cooler with highs in the lower 80s. Chance of rain 50%.
Thursday Night... Mostly clear. A 20% chance of showers. Lows in the lower 60s. Highs in the mid 80s.
Friday... Mostly clear. A 20% chance of showers. Lows in the lower 60s. Highs in the mid 80s.
Friday Night... Mostly clear in the evening, then partly cloudy with a chance of showers with a slight chance of thunderstorms after midnight. Lows in the lower 60s. Chance of rain 30%.
POP = Probability of Precipitation
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