The highest day temperature in August 2025 was 100°F. The lowest night temperature was 50°F. The average values for day and night temperatures during August were 85.7°F и 66.6°F respectivly.

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

Precipitation total in August for Naperville is 0.8 in.

The average wind speed in August is 6.8 mph. It makes August one of the most windless months of the year for Naperville.

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 Naperville in August is 9.0 hours.