December weather forecastSaint John, VI

December
Weather in December
Closing the year, December in Saint John brings the cool breath of winter mixed with a tropical climate. The slower pace of the city matches the gentle coolness in the air. While the temperature sees a minor dip, December’s significant change lies in its reduced rainfall, going down to 4.7" (119mm). Captivating locals and tourists alike, Saint John’s December weather, with its mix of warm days and cool nights, provides an ideal setting for holiday festivities and year-end celebrations.Temperature
January through March and December are identified as the coldest months, with an average high-temperature of 82.4°F (28°C).Rainfall
In December, the rain falls for 14 days. Throughout December, 4.69" (119mm) of precipitation is accumulated. In Saint John, during the entire year, the rain falls for 156 days and collects up to 49.69" (1262mm) of precipitation.Ocean temperature
In Saint John, the average seawater temperature in December is 80.6°F (27°C).Note: For swimming, diving, and other water activities, temperatures between 77°F (25°C) and 84.2°F (29°C) are perceived as very enjoyable and pleasurable for prolonged periods without feeling uncomfortable.
Daylight
With an average of 11h and 6min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 6:35 am and sunset at 5:41 pm. On the last day of December, sunrise is at 6:50 am and sunset at 5:53 pm AST.
Sunshine
The months with the least sunshine are November and December, with an average of 7h of sunshine.UV index
With an average maximum UV index of 7, December is the month with the lowest UV index. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV radiation for average individuals.Note: The maximum UV index, 7 during December, leads to the following recommendations:
Persist with safeguards and heed sun safety doctrines. Keeping sunburn at bay is of prime importance. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Be careful! The Sun's UV radiation is accentuated by reflecting off sand and water.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Saint John, VI
- Average high temperature in December: 82°F
The warmest months (with the highest average high temperature) are August and September (88°F).
The months with the lowest average high temperature are January, February, March and December (82°F).
- Average low temperature in December: 72°F
The months with the highest average low temperature are June, July, August, September and October (75°F).
The coldest months (with the lowest average low temperature) are January, February and March (70°F).
Average rainfall in December
Saint John, VI
- Average rainfall in December: 4.7"
The wettest months (with the highest rainfall) are October and November (6.3").
The driest month (with the least rainfall) is February (2.1").
Average rainfall days in December
Saint John, VI
- Average rainfall days in December: 14 days
The months with the highest number of rainy days are September and October (16 days).
The month with the least rainy days is April (9 days).
Average sea temperature in December
Saint John, VI
- Average sea temperature in December: 81°F
The best months for swimming (with the highest average sea temperature) are September and October (84°F).
The coldest months (with the lowest average sea temperature) are January, February, March and April (79°F).
Average daylight in December /
Average sunshine in December
Saint John, VI
- Average daylight in December: 11h and 6min
The month with the longest days is June (Average daylight: 13h and 12min).
The month with the shortest days is December (Average daylight: 11h and 6min).
- Average sunshine in December: 7h
The months with the most sunshine are March, April, July and August (Average sunshine: 9h).
The months with the least sunshine are November and December (Average sunshine: 7h).
Average UV index in December
Saint John, VI
- Average UV index in December: 7
The months with the highest UV index are March, April, May, June, July, August and September (UV index 12).
The month with the lowest UV index is December (UV index 7).





