Sioux Falls, South Dakota – Thunderstorms and dangerous heat will dominate South Dakota’s weekend weather, with Sioux Falls caught in the crosshairs Saturday afternoon and evening.
According to the National Weather Service in Sioux Falls, temperatures on Saturday, June 28, will climb to 93°F, with heat index values possibly exceeding 105°F by mid-afternoon. A 30 to 60 percent chance of thunderstorms is expected by Saturday night, with gusty winds and heavy rainfall possible along major corridors like I-29 and Highway 42.
Strong storms could trigger localized flooding and dangerous lightning late Saturday. Residents with outdoor plans or travel scheduled Saturday evening should monitor alerts closely and prepare for rapid weather changes. Power outages and travel delays are possible, particularly during peak evening hours.
The summer pattern doesn’t let up quickly. Sunday brings another shot of thunderstorms and highs near 87°F, followed by mostly clear skies and a slight cooldown into early next week. Heat and humidity will ease slightly Monday and Tuesday, but more showers could arrive by midweek.
Five-Day Forecast for Sioux Falls (June 27 – July 2):
- Friday: Patchy fog, then sunny. High near 85°F.
- Saturday: High of 93°F. Chance of storms late (60%). Heat index may top 105°F.
- Sunday: High of 87°F. More thunderstorms likely, especially afternoon and evening.
- Monday: Sunny, high around 86°F.
- Tuesday (July 2): Sunny with highs in the upper 80s — ideal for July 4 prep.
