Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average sea temperature in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December brings a decrease in the average high-temperature, falling from November's chilly 44.8°F (7.1°C) to an icy 35.1°F (1.7°C). During December, the average low-temperature is a subzero cold 25.7°F (-3.5°C).Humidity
In December, the average relative humidity is 78%.Rainfall
December is the month with the most rainfall. Rain falls for 11.5 days and accumulates 3.94" (100mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In December, it is snowing for 7.9 days. Throughout December, 3.78" (96mm) of snow is accumulated. In Sullivan, during the entire year, snow falls for 48.1 days and aggregates up to 23.82" (605mm) of snow.Ocean temperature
In Sullivan, the average seawater temperature in December is 45.3°F (7.4°C).Note: It is advised against swimming in 45.3°F (7.4°C) when it drops below 50°F (10°C). Such temperatures can cause extreme cold shock, leading to hyperventilation.
Daylight
The month with the shortest days is December, with an average of 8h and 54min of daylight.On the first day of December, sunrise is at 6:49 am and sunset at 3:54 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 4:02 pm EST.
Sunshine
In Sullivan, the average sunshine in December is 4.4h.UV index
The months with the lowest UV index in Sullivan are January through March, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for average individuals.Note: The maximum UV index, 2 during December, leads to the following recommendations:
While most can endure approximately an hour in the sun without burning, children always require protection from sunlight. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
What is the rainiest month?
How much does it rain in December?
How many days does it snow in December?
How cold is the water in December?
What is the month with the shortest days?
How many hours of daylight does Sullivan have in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Sullivan, ME
- Average high temperature in December: 35.1°F
The warmest month (with the highest average high temperature) is August (73.4°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in December: 25.7°F
The month with the highest average low temperature is July (58.1°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in December
Sullivan, ME
- Average pressure in December: 29.99"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
Sullivan, ME
- Average wind speed in December: 10.1mph
The windiest month (with the highest average wind speed) is January (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in December
Sullivan, ME
- Average humidity in December: 78%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is November (76%).
Average rainfall in December
Sullivan, ME
- Average rainfall in December: 3.94"
The wettest month (with the highest rainfall) is December (3.94").
The driest month (with the least rainfall) is July (1.57").
Average rainfall days in December
Sullivan, ME
- Average rainfall days in December: 11.5 days
The month with the highest number of rainy days is April (15.5 days).
The month with the least rainy days is February (7.5 days).
Average snowfall in December
Sullivan, ME
- Average snowfall in December: 3.78"
The month with the highest snowfall is February (5.75").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Sullivan, ME
- Average snowfall days in December: 7.9 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average sea temperature in December
Sullivan, ME
- Average sea temperature in December: 45.3°F
The best month for swimming (with the highest average sea temperature) is August (56.8°F).
The coldest month (with the lowest average sea temperature) is March (38°F).
Average daylight in December /
Average sunshine in December
Sullivan, ME
- Average daylight in December: 8h and 5min
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 2min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is February (Average sunshine: 4h and 6min).
Average sunshine days in December
Sullivan, ME
- Average sunshine days in December: 14.1 days
The month with the most sunshine days is August (18.7 days).
The month with the least sunshine days is April (11.2 days).
Average UV index in December
Sullivan, 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
Sullivan, ME
- Average cloud cover in December: 53
The month with the most cloud cover is February (Cloud cover 56).
The months with the least cloud cover are August and September (Cloud cover 35).
Average visibility in December
Sullivan, ME
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Sullivan, Maine, USA
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