The highest day temperature in July 2025 was 94°F. The lowest night temperature was 49°F. The average values for day and night temperatures during July were 79.8°F и 61.1°F respectivly.

The average sea surface temperature in July 2025 for Duluth was 64.9°F. The maximum and minimum values were 59.0°F and 73.6°F respectively.

Most of the days in July are cloudy but you can also expect sunny or gloomy days.

Precipitation total in July for Duluth is 1.3 in. It makes july the most rainy month of the year.

The average wind speed in July is 6.0 mph. This value is relatively stable throughout the year.

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 Duluth in July is 9.2 hours.