The highest day temperature in August 2025 was 95°F. The lowest night temperature was 40°F. The average values for day and night temperatures during August were 83.5°F и 63.5°F respectivly.

Most of the days in August are sunny but you can also expect cloudy and gloomy days.

Precipitation total in August for Sioux Falls is 0.7 in.

The average wind speed in August is 9.4 mph. It makes August one of the most windless months of the year for Sioux Falls.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Sioux Falls in August is 9.0 hours.