The highest day temperature in September 2026 was 93°F. The lowest night temperature was 54°F. The average values for day and night temperatures during September were 73.1°F и 63.8°F respectivly.

The average sea surface temperature in September 2026 for Mystic was 70.3°F. The maximum and minimum values were 65.4°F and 72.6°F respectively.

You can expect various weather conditions during September. Be ready for sunny, cloudy or even gloomy days.

Precipitation total in September for Mystic is 1.2 in.

The average wind speed in September is 8.6 mph.

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 Mystic in September is 7.0 hours.