The highest day temperature in September 2025 was 76°F. The lowest night temperature was 54°F. The average values for day and night temperatures during September were 68.0°F и 64.4°F respectivly.

The average sea surface temperature in September 2025 for Provincetown was 66.8°F. The maximum and minimum values were 63.0°F and 69.4°F respectively.

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

Precipitation total in September for Provincetown is 0.9 in. It makes september one of the least rainy months of the year.

The average wind speed in September is 10.5 mph. It makes September one of the most windless months of the year for Provincetown.

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 Provincetown in September is 7.2 hours.