The highest day temperature in September 2026 was 72°F. The lowest night temperature was 47°F. The average values for day and night temperatures during September were 61.9°F и 53.2°F respectivly.

The average sea surface temperature in September 2026 for Whidbey Island was 58.8°F. The maximum and minimum values were 55.8°F and 61.0°F respectively.

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

Precipitation total in September for Whidbey Island is 0.8 in. It makes september one of the least rainy months of the year.

The average wind speed in September is 5.4 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 Whidbey Island in September is 7.3 hours.