December weather forecast
Rota, Northern Mariana Islands, USA

December continues the trend from November, with reduced average rainfall of 5.7" (145mm) indicating a return to conditions seen at the beginning of the year. The sea temperatures start to come down subtly, although they remain relatively warm for aquatic activities in Rota. The daylight hours continue their decline, and sunshiners hours mirror those from February. However, the UV index lessens slightly, hinting at the mild cooling trend that will carry into the New Year. Overall, December embodies a return to less rainy conditions, wrapping the year with a gentle shift out of the wet season.

Temperature

The onset of December notes an average high-temperature of a still hot 86°F (30°C), subtly shifted from November's 87.8°F (31°C). Rota experiences a consistent average temperature of 75.2°F (24°C) throughout the nights in December.

Rainfall

In Rota, in December, during 22 rainfall days, 5.75" (146mm) of precipitation is typically accumulated. Throughout the year, in Rota, there are 247 rainfall days, and 94.29" (2395mm) of precipitation is accumulated.

Ocean temperature

In Rota, in December, the average water temperature is 82.4°F (28°C).
Note: For any water activity, surface water temperatures between 77°F (25°C) and 84.2°F (29°C) are considered as excellent and extremely pleasant for lengthened periods.

Daylight

With an average of 11h and 18min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 6:27 am and sunset at 5:48 pm. On the last day of December, in Rota, sunrise is at 6:43 am and sunset at 6:01 pm ChST.

Sunshine

In December, the average sunshine in Rota is 5h.

UV index

With an average maximum UV index of 9, December is the month with the lowest UV index. A UV Index of 8 to 10 symbolizes a very high threat to health from exposure to the Sun's UV radiation for the average person.
Note: The maximum UV index of 9 during December leads to these instructions:
Take special precautions, as unprotected skin can be damaged and can burn quickly. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Broad-spectrum sunscreen with an SPF of 30 or above should be applied generously and reapplied every two hours and right after any outdoor activity or swim. Heed this! UV intensity is much stronger when reflected off sand and water.