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Grass Lake, SD 7-Day Night Weather Forecast
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Grass Lake, SD Weather Forecast
Grass Lake, SD Weather Forecast Date: 221 PM CDT Fri Sep 18 2026
The area/counties/county of: Codington, including the city of Watertown.or toggle through each period.
This Afternoon... Cloudy with a 50% chance of showers. Patchy fog. Cooler. Near steady temperature in the lower 60s. East winds 10 to 15 mph with gusts up to 25 mph.
Tonight... Cloudy. A chance of showers, mainly in the evening. Patchy fog in the evening, then areas of fog after midnight. Near steady temperature around 60. Northeast winds 5 to 10 mph. Chance of rain 50%.
Saturday... Areas of fog in the morning. Cloudy. Highs in the mid 60s. Northeast winds 10 to 15 mph with gusts up to 25 mph.
Saturday Night... Mostly cloudy. Lows in the lower 50s. Northeast winds 10 to 15 mph.
Sunday... Mostly cloudy. Highs in the mid 60s. Northeast winds 10 to 15 mph with gusts up to 25 mph.
Sunday Night... Cloudy. A slight chance of showers in the evening, then a chance of showers after midnight. Lows in the upper 40s. Chance of rain 50%.
Monday... Mostly cloudy. A slight chance of showers in the morning. Highs in the lower 60s. Chance of rain 20%.
Monday Night... Mostly cloudy. Lows in the mid 40s. Highs in the mid 60s.
Tuesday... Mostly cloudy. Lows in the mid 40s. Highs in the mid 60s.
Tuesday Night... Partly cloudy. Lows in the upper 40s.
Wednesday... Partly sunny. Highs in the upper 60s.
Wednesday Night... Mostly cloudy. A slight chance of showers in the evening, then a chance of showers after midnight. Lows in the lower 50s. Chance of rain 30%.
POP = Probability of Precipitation
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