December weather forecastUnion, ME

December

Weather in December

The first month of the winter, December, is also an icy month in Union, Maine, with an average temperature fluctuating between 26.6°F (-3°C) and 35.8°F (2.1°C).

Temperature

The arrival of December signals a shift in temperature, down from a frosty 44.8°F (7.1°C) in November to a wintry 35.8°F (2.1°C). Nighttime temperatures in December average to a subzero cold 26.6°F (-3°C).

Humidity

In Union, the average relative humidity in December is 78%.

Rainfall

The wettest months are April, November and December, with an average 1.42" (36mm) of rainfall.

Snowfall

January through April, November and December are months with snowfall. In Union, Maine, during December, snow falls for 5.7 days and regularly aggregates up to 0.98" (25mm) of snow. In Union, during the entire year, snow falls for 32.6 days and aggregates up to 7.05" (179mm) of snow.

Daylight

With an average of 8h and 54min of daylight, December has the shortest days of the year in Union.
On the first day of December, sunrise is at 6:53 am and sunset at 3:59 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 4:08 pm EST.

Sunshine

December has the least sunshine of the year, with an average of 4.6h of sunshine.

UV index

The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A maximum high daily UV index of 2 during December translates into the following directions:
Babies, children, and individuals with sensitive skin should always have protection against extended sun exposure. Given the potency of the midday Sun's UV radiation, one should avoid prolonged exposure. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

Union in December has an average high-temperature of 35.8°F (2.1°C) and an average low-temperature of 26.6°F (-3°C).

In December, the average relative humidity in Union is 78%.

The wettest months in Union are April, November and December, with an average 1.42" (36mm) of rainfall.

In Union, Maine, during December, the rain falls for 9.7 days and regularly aggregates up to 1.42" (36mm) of precipitation.

In Union, Maine, in December, during 5.7 snowfall days, 0.98" (25mm) of snow is typically accumulated.

The month with the shortest days in Union, Maine, is December, with an average of 8h and 54min of daylight.

In Union, the average day length in December is 8h and 56min.

On the first day of December, sunrise is at 6:53 am and sunset at 3:59 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 4:08 pm EST.

December has the least sunshine of the year in Union, with an average of 4.6h of sunshine.

In December, the average sunshine duration in Union is 4.6h.

The months with the lowest UV index in Union, Maine, are January through March, November and December, with an average maximum UV index of 2.

In December, the average daily maximum UV index in Union is 2. A UV Index of 2, and less, symbolizes a low health threat from exposure to the Sun's UV radiation.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Union, ME

  • Average high temperature in December: 35.8°F

The warmest month (with the highest average high temperature) is August (70.7°F).
The month with the lowest average high temperature is January (29.8°F).

  • Average low temperature in December: 26.6°F

The months with the highest average low temperature are July and August (59.4°F).
The coldest month (with the lowest average low temperature) is January (19.9°F).

Average pressure in December
Union, 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
Union, ME

  • Average wind speed in December: 12.4mph

The windiest month (with the highest average wind speed) is January (12.9mph).
The calmest months (with the lowest average wind speed) are July and August (7.2mph).

Average humidity in December
Union, ME

  • Average humidity in December: 78%

The months with the highest relative humidity are June and July (84%).
The month with the lowest relative humidity is November (76%).

Average rainfall in December
Union, ME

  • Average rainfall in December: 1.42"

The wettest months (with the highest rainfall) are April, November and December (1.42").
The driest month (with the least rainfall) is September (0.75").

Average rainfall days in December
Union, ME

  • Average rainfall days in December: 9.7 days

The month with the highest number of rainy days is April (13.2 days).
The months with the least rainy days are January and February (6.8 days).

Average snowfall in December
Union, ME

  • Average snowfall in December: 0.98"

The month with the highest snowfall is January (1.69").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in December
Union, ME

  • Average snowfall days in December: 5.7 days

The month with the highest number of snowfall days is January (8 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Union, 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 36min

The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is December (Average sunshine: 4h and 36min).

Average sunshine days in December
Union, ME

  • Average sunshine days in December: 15.7 days

The month with the most sunshine days is September (19.9 days).
The month with the least sunshine days is April (13.8 days).

Average UV index in December
Union, 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
Union, ME

  • Average cloud cover in December: 51

The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 31).

Average visibility in December
Union, 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).