Weather in Sandakan in December

Shoulder season. December sits in between. You will get good days and you will lose some. You should expect rain on 29 days of the month, which is more days wet than dry.

Sandakan barely has seasons. December scores 54 out of 100 against a best of 57 in February — a gap small enough that the month you choose matters far less here than the week you choose.

Rain on 29 of the month's 31 days, 12 of them heavy. At that frequency a wet-weather backup is not a contingency, it is the itinerary — book the indoor things first and treat the clear days as the bonus. Natural fibres and a second shirt for the day. At 87% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average December reaches 30 °C; the day barely swings — 1.7 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest December day reached 29.7 °C and the coldest night fell to 24.1 °C, and the wettest single day dropped 81 mm — roughly 23% of the month's rain in one day.

December is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest December on record still delivered 569 mm against 132 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 359 mm average is a reasonable planning figure, not a promise.

Wind is light at 7 km/h, so the temperature on the page is close to the temperature on your skin, and humidity at 87% is the real story though — it is the number that decides how the day feels, not the 28 °C.

How December sits in the year

Temperatures hold steady either side: 28.2 °C in November, 28 here, 27.6 in January. Nothing about the timing within the month matters much.

Daylight in December

Sandakan sits close enough to the equator that daylight barely moves all year — 11.8 hours in December, against a range of just 0.7 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 28.7 °C in December — warm enough that the water offers no relief from the heat. The sea peaks at 29.7 °C in May and bottoms out at 27.8 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Shoulder. The value months — prices ease off and you get the place closer to itself.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

December in Sandakan versus nearby

If Sandakan is one option among several, the nearby comparison is worth making. Kota Kinabalu is the weaker option in December — 2.1 °C warmer, 4 days less rain. Zamboanga is close enough to be a coin toss — within a degree on temperature, 7 days less rain.

So: December is effectively as good as it gets here — 3 points behind February, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Sandakan

See all twelve months in Sandakan, or where else to go in December.