The highest day temperature in September 2023 was 104°F. The lowest night temperature was 79°F. The average values for day and night temperatures during September were 95.8°F и 82.8°F respectivly.

The average sea surface temperature in September 2023 for Galveston Island was 90.6°F. The maximum and minimum values were 88.8°F and 93.0°F respectively.

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

Precipitation total in September for Galveston Island is 1.5 in. It makes september one of the most rainy months of the year.

The average wind speed in September is 7.6 mph. It makes September the most windless month of the year for Galveston Island.

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 Galveston Island in September is 7.8 hours.