December weather forecastTinian International Airport, Northern Mariana Islands, USA
December
Weather in December
December witnesses similar climatic conditions as November, setting the ground for cooler weather and shortening daylight hours. The month forecasts rainfall of 4.8" (122mm) over 22 days, providing the region with a moist and tranquil atmosphere. The noticeable drop in the UV Index suggests that the intensity of sunlight is less harsh. Even in the closing month of the year, sea temperature stays agreeably warm. This month's weather conditions make it an ideal time for visitors to explore the city without concern for excessive heat.Temperature
The shift into December reveals an average high-temperature of a still tropical 86°F (30°C), maintaining the same temperature as the previous month. Nighttime temperature experiences an average drop to a moderately hot 75.2°F (24°C) in December.Rainfall
In Tinian International Airport, during December, the rain falls for 22 days and regularly aggregates up to 4.76" (121mm) of precipitation. Throughout the year, there are 247 rainfall days, and 79.21" (2012mm) of precipitation is accumulated.Ocean temperature
In Tinian International Airport, in December, the average water temperature is 82.9°F (28.3°C).Note: Water temperature ranging between 77°F (25°C) and 84.2°F (29°C) is considered very warm and pleasing for everyone. It allows for enjoyable water activities over extended periods without discomfort.
Daylight
December has the shortest days of the year, with an average of 11h and 18min of daylight.On the first day of the month, sunrise is at 6:27 am and sunset at 5:45 pm. On the last day of December, sunrise is at 6:42 am and sunset at 5:58 pm ChST.
Sunshine
The months with the least sunshine are August through December, with an average of 5h of sunshine.UV index
The months with the lowest UV index are November and December, with an average maximum UV index of 9. A UV Index value of 8 to 10 symbolizes a very high health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index, 9 in December, converts into the following recommendations:
Take all necessary measures. Eyes and skin are at risk if left unprotected. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Directly after outdoor activities or swimming, a broad-spectrum sunscreen with SPF 30+ should be applied generously and reapplied frequently. Warning! The reflection of sand and water increases the UV dose.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Tinian International Airport, Northern Mariana Islands, USA
- Average high temperature in December: 86°F
The warmest months (with the highest average high temperature) are June, July, August, September and October (88°F).
The months with the lowest average high temperature are January, February and March (84°F).
- Average low temperature in December: 75°F
The months with the highest average low temperature are May, June, July, August, September, October and November (77°F).
The coldest months (with the lowest average low temperature) are February and March (73°F).
Average rainfall in December
Tinian International Airport, Northern Mariana Islands, USA
- Average rainfall in December: 4.8"
The wettest month (with the highest rainfall) is September (12.8").
The driest month (with the least rainfall) is February (2.9").
Average rainfall days in December
Tinian International Airport, Northern Mariana Islands, USA
- Average rainfall days in December: 22 days
The month with the highest number of rainy days is August (23 days).
The month with the least rainy days is April (18 days).
Average sea temperature in December
Tinian International Airport, Northern Mariana Islands, USA
- Average sea temperature in December: 83°F
The best month for swimming (with the highest average sea temperature) is July (85.4°F).
The coldest months (with the lowest average sea temperature) are January, February and March (82°F).
Average daylight in December /
Average sunshine in December
Tinian International Airport, Northern Mariana Islands, USA
- Average daylight in December: 11h and 18min
The month with the longest days is June (Average daylight: 13h and 0min).
The month with the shortest days is December (Average daylight: 11h and 18min).
- Average sunshine in December: 5h
The months with the most sunshine are March, April, May and June (Average sunshine: 7h).
The months with the least sunshine are August, September, October, November and December (Average sunshine: 5h).
Average UV index in December
Tinian International Airport, Northern Mariana Islands, USA
- Average UV index in December: 9
The months with the highest UV index are February, March, April, May, June, July, August and September (UV index 12).
The months with the lowest UV index are November and December (UV index 9).





