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Sister Lake, SC 7-Day Night Weather Forecast
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Sister Lake, SC Weather Forecast
Sister Lake, SC Weather Forecast Date: 608 PM EDT Sat Aug 15 2026
The area/counties/county of: Barnwell, including the cities of: Barnwell, Williston, and Blackville.or toggle through each period.
Tonight... Partly cloudy. A slight chance of showers and thunderstorms this evening. Patchy fog after midnight. Lows in the mid 70s. Light and variable winds. Chance of rain 20%.
Sunday... Mostly sunny. Patchy fog in the morning. A chance of showers and thunderstorms in the afternoon. Humid with highs in the mid 90s. Light and variable winds. Chance of rain 30%. Heat index values up to 108.
Sunday Night... Partly cloudy. A chance of thunderstorms in the evening. Humid with lows in the mid 70s. Light and variable winds, becoming southwest around 5 mph after midnight. Chance of precipitation 30%.
Monday... Sunny with highs in the upper 90s. West winds around 5 mph. Heat index values up to 109.
Monday Night... Mostly clear. Lows in the upper 70s. Southwest winds around 5 mph.
Tuesday... Sunny. Highs in the upper 90s. Heat index values up to 110.
Tuesday Night... Partly cloudy with a chance of showers and thunderstorms. Lows in the mid 70s. Chance of rain 30%.
Wednesday... Sunny. Highs in the mid 90s.
Wednesday Night... Mostly clear. Lows in the mid 70s.
Thursday... Sunny. Highs in the upper 90s.
Thursday Night... Partly cloudy with a chance of showers. Lows in the mid 70s. Chance of rain 30%.
Friday... Mostly sunny. A chance of showers and thunderstorms in the afternoon. Highs in the mid 90s. Chance of rain 40%.
Friday Night... Mostly cloudy in the evening, then becoming partly cloudy. A chance of thunderstorms in the evening. A chance of showers. Lows in the lower 70s. Chance of rain 40%.
POP = Probability of Precipitation
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