National Weather Service Forecast for: Sioux Falls SD
Issued by: National Weather Service Sioux Falls, SD
Updated: 2:39 am CDT Aug 20, 2026
 
Overnight

Overnight: Mostly clear, with a low around 60. South wind around 5 mph.
Mostly Clear

 Thursday

Thursday: A 20 percent chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 86. South southwest wind 5 to 15 mph, with gusts as high as 25 mph.
Mostly Sunny
then Slight
Chance
T-storms
 Thursday
Night
Thursday Night: A 20 percent chance of showers and thunderstorms before 9pm. Mostly clear, with a low around 62. West southwest wind 5 to 10 mph becoming light and variable in the evening.
Slight Chance
T-storms then
Mostly Clear
 Friday

Friday: Sunny, with a high near 86. Calm wind becoming north around 5 mph in the afternoon.
Sunny

 Friday
Night
Friday Night: Mostly clear, with a low around 61. North northeast wind around 5 mph becoming calm in the evening.
Mostly Clear

 Saturday

Saturday: Sunny, with a high near 82. North wind 5 to 10 mph.
Sunny

 Saturday
Night
Saturday Night: Partly cloudy, with a low around 58.
Partly Cloudy

 Sunday

Sunday: Partly sunny, with a high near 80.
Partly Sunny

 Sunday
Night
Sunday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 62.
Chance
T-storms
Lo 60 °F Hi 86 °F Lo 62 °F Hi 86 °F Lo 61 °F Hi 82 °F Lo 58 °F Hi 80 °F Lo 62 °F

Hazardous Weather Outlook
 

Overnight
 
 Mostly clear, with a low around 60. South wind around 5 mph.
Thursday
 
 A 20 percent chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 86. South southwest wind 5 to 15 mph, with gusts as high as 25 mph.
Thursday Night
 
 A 20 percent chance of showers and thunderstorms before 9pm. Mostly clear, with a low around 62. West southwest wind 5 to 10 mph becoming light and variable in the evening.
Friday
 
 Sunny, with a high near 86. Calm wind becoming north around 5 mph in the afternoon.
Friday Night
 
 Mostly clear, with a low around 61. North northeast wind around 5 mph becoming calm in the evening.
Saturday
 
 Sunny, with a high near 82. North wind 5 to 10 mph.
Saturday Night
 
 Partly cloudy, with a low around 58.
Sunday
 
 Partly sunny, with a high near 80.
Sunday Night
 
 A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 62.
Monday
 
 Partly sunny, with a high near 82.
Monday Night
 
 Partly cloudy, with a low around 64.
Tuesday
 
 Mostly sunny, with a high near 84.
Tuesday Night
 
 Mostly clear, with a low around 62.
Wednesday
 
 Mostly sunny, with a high near 82.

 

Forecast from NOAA-NWS for Sioux Falls SD.