December weather forecastDeer Isle, ME
December
Weather in December
December symbolizes the official start of the winter period in Deer Isle, Maine. Temperatures aggressively decline to an average of 36.7°F (2.6°C), making it the second coldest month. With shorter daylight hours and occasional snowfall, the city turns into a winter wonderland. Despite the frosty temperatures, festivities during the holiday season bring warmth and joy to the city. It's a great time for winter sports and other snow-based activities.Temperature
During the shift to December, a minor reduction in average high-temperature is observed, shifting from a chilly 45.3°F (7.4°C) in November to an icy 36.7°F (2.6°C). The December nights show a slight decrease to a mean low-temperature of 27.7°F (-2.4°C).Humidity
In Deer Isle, Maine, the average relative humidity in December is 78%.Rainfall
In Deer Isle, in December, during 8.4 rainfall days, 1.89" (48mm) of precipitation is typically accumulated. In Deer Isle, during the entire year, the rain falls for 115.5 days and collects up to 17.95" (456mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In Deer Isle, in December, during 5.9 snowfall days, 1.81" (46mm) of snow is typically accumulated. Throughout the year, there are 29.2 snowfall days, and 9.65" (245mm) of snow is accumulated.Ocean temperature
In Deer Isle, the average seawater temperature in December is 45.5°F (7.5°C).Note: Engaging in a swim in 45.5°F (7.5°C) can threaten life. Brief exposure to 55.4°F (13°C) waters is uneasy, and submersion below 50°F (10°C) can lead to cold shock and disrupted breathing patterns, varying by individual.
Daylight
December has the shortest days of the year, with an average of 8h and 54min of daylight.On the first day of the month, sunrise is at 6:50 am and sunset at 3:57 pm. On the last day of December, sunrise is at 7:10 am and sunset at 4:05 pm EST.
Sunshine
December has the least sunshine of the year, with an average of 4.5h of sunshine.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index reading of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: In December, the UV index of 2 transforms into the following advice:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. A hat with a broad brim is indispensable, filtering out up to half of UV rays. Be mindful! The reflection from snow can increase the Sun's UV radiation nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Deer Isle, ME
- Average high temperature in December: 36.7°F
The warmest month (with the highest average high temperature) is August (68.9°F).
The month with the lowest average high temperature is January (31.5°F).
- Average low temperature in December: 27.7°F
The month with the highest average low temperature is August (59.9°F).
The coldest month (with the lowest average low temperature) is January (21°F).
Average pressure in December
Deer Isle, ME
- Average pressure in December: 30"Hg
The month with the highest atmospheric pressure is September (30.04"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Deer Isle, ME
- Average wind speed in December: 13.9mph
The windiest month (with the highest average wind speed) is January (14.4mph).
The calmest months (with the lowest average wind speed) are July and August (7.8mph).
Average humidity in December
Deer Isle, ME
- Average humidity in December: 78%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is November (76%).
Average rainfall in December
Deer Isle, ME
- Average rainfall in December: 1.89"
The wettest month (with the highest rainfall) is October (2.09").
The driest month (with the least rainfall) is September (0.91").
Average rainfall days in December
Deer Isle, ME
- Average rainfall days in December: 8.4 days
The month with the highest number of rainy days is July (12.8 days).
The month with the least rainy days is February (5.3 days).
Average snowfall in December
Deer Isle, ME
- Average snowfall in December: 1.81"
The month with the highest snowfall is February (2.32").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Deer Isle, ME
- Average snowfall days in December: 5.9 days
The month with the highest number of snowfall days is January (7.7 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average sea temperature in December
Deer Isle, ME
- Average sea temperature in December: 45.6°F
The best month for swimming (with the highest average sea temperature) is August (58.6°F).
The coldest month (with the lowest average sea temperature) is March (38.2°F).
Average daylight in December /
Average sunshine in December
Deer Isle, ME
- Average daylight in December: 8h and 54min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 4h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is December (Average sunshine: 4h and 30min).
Average sunshine days in December
Deer Isle, ME
- Average sunshine days in December: 16.3 days
The month with the most sunshine days is September (19.9 days).
The month with the least sunshine days is July (15.4 days).
Average UV index in December
Deer Isle, ME
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in December
Deer Isle, ME
- Average cloud cover in December: 51
The months with the most cloud cover are February and March (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in December
Deer Isle, ME
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





