| NWS Forecast for: Union County Issued by: National Weather Service Sioux Falls, SD Last Update: 539 PM CDT Wed Sep 16 2026 |  |
| Tonight: Cloudy. A chance of sprinkles this evening. Patchy fog after midnight. Near steady temperature in the lower 60s. South winds around 5 mph. Thursday: Patchy fog in the morning. Mostly cloudy with a chance of sprinkles in the morning, then partly sunny in the afternoon. Humid with highs in the mid 70s. North winds around 5 mph, becoming east in the afternoon. Thursday Night: Mostly cloudy with a chance of thunderstorms. A chance of showers in the evening, then showers likely after midnight. Humid with lows in the mid 60s. East winds 10 to 15 mph with gusts up to 25 mph. Chance of rain 70 percent. Friday: Mostly cloudy with a chance of showers and thunderstorms in the morning, then mostly sunny with a slight chance of showers and thunderstorms in the afternoon. Warmer with highs in the mid 80s. Southeast winds 15 to 20 mph, becoming southwest 10 to 15 mph in the afternoon. Chance of rain 50 percent. Friday Night: Partly cloudy with a chance of showers with a slight chance of thunderstorms in the evening, then mostly cloudy after midnight. Humid with lows in the lower 60s. Northwest winds 5 to 10 mph. Chance of rain 50 percent. Saturday: Cloudy. Not as warm with highs around 70. Saturday Night: Mostly cloudy. Lows in the upper 50s. Sunday: Cloudy with a 40 percent chance of showers. Highs in the mid 60s. Sunday Night: Mostly cloudy. A chance of showers after midnight. Lows in the mid 50s. Chance of rain 40 percent. Monday: Mostly cloudy. A chance of showers in the morning. Highs in the mid 60s. Chance of rain 40 percent. Monday Night: Mostly cloudy. Lows in the lower 50s. Tuesday: Mostly cloudy in the morning, then becoming mostly sunny. Highs in the upper 60s. Tuesday Night: Partly cloudy in the evening, then becoming mostly cloudy. Lows in the mid 50s. Wednesday: Partly sunny. Highs in the lower 70s. | |
| Zone Forecast: Union County | |
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