Expires:202607260900;;606806 FPUS53 KFSD 260104 ZFPFSD Zone Forecasts for SE South Dakota/NW Iowa/SW Minnesota National Weather Service Sioux Falls SD 803 PM CDT Sat Jul 25 2026 SDZ069-260900- Yankton- Including the city of Yankton 803 PM CDT Sat Jul 25 2026 ...EXTREME HEAT WARNING IN EFFECT UNTIL 8 PM CDT SUNDAY... ...SEVERE THUNDERSTORM WATCH 513 IN EFFECT UNTIL 11 PM CDT THIS EVENING... .TONIGHT...Mostly cloudy with a chance of showers. A chance of thunderstorms. Some thunderstorms may be severe with damaging winds and large hail. Some thunderstorms may be severe. Lows in the mid 70s. South winds around 10 mph, becoming east after midnight. Chance of rain 50 percent. Heat index values up to 114 early this evening. .SUNDAY...Mostly cloudy in the morning, then clearing. Hot with highs around 100. South winds 10 to 15 mph. Gusts up to 30 mph in the afternoon. Heat index values up to 113 in the afternoon. .SUNDAY NIGHT...Partly cloudy with a slight chance of showers and thunderstorms in the evening, then mostly clear after midnight. Humid with lows in the mid 70s. South winds 10 to 15 mph, becoming west 5 to 10 mph after midnight. Chance of rain 20 percent. Heat index values up to 114 early in the evening. .MONDAY...Sunny, hot with highs in the upper 90s. North winds 5 to 10 mph, becoming northeast in the afternoon. .MONDAY NIGHT...Mostly clear in the evening, then becoming mostly cloudy. Humid with lows in the lower 70s. East winds 5 to 10 mph. Heat index values in the upper 90s early in the evening. .TUESDAY...Mostly sunny. Highs in the lower 90s. .TUESDAY NIGHT...Mostly clear in the evening, then becoming partly cloudy. Lows in the upper 60s. .WEDNESDAY...Partly sunny in the morning, then clearing. Highs in the mid 90s. .WEDNESDAY NIGHT...Mostly clear in the evening, then becoming partly cloudy. Lows in the lower 70s. .THURSDAY...Mostly cloudy in the morning, then becoming mostly sunny. A chance of thunderstorms in the morning. A chance of showers. Highs in the lower 90s. Chance of rain 40 percent. Heat index values in the upper 90s in the afternoon. .THURSDAY NIGHT...Partly cloudy with a chance of showers. Lows in the upper 60s. Chance of rain 50 percent. .FRIDAY...Partly sunny in the morning, then clearing. Highs around 90. .FRIDAY NIGHT...Mostly clear. Lows in the mid 60s. .SATURDAY...Mostly sunny. Highs around 90. $$