The highest day temperature in September 2025 was 94°F. The lowest night temperature was 77°F. The average values for day and night temperatures during September were 89.4°F и 78.7°F respectivly.

The average sea surface temperature in September 2025 for Sandakan was 89.6°F. The maximum and minimum values were 88.8°F and 90.6°F respectively.

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

Precipitation total in September for Sandakan is 7.6 in. It makes september one of the most rainy months of the year.

The average wind speed in September is 4.5 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 Sandakan in September is 6.6 hours.