December weather forecastMukilteo, WA
December
Weather in December
December, the first month of the winter in Mukilteo, is also an icy month, with an average temperature varying between 42.6°F (5.9°C) and 35.4°F (1.9°C).Temperature
In Mukilteo, the month of December is known for its lowest average temperatures, reaching a high of 42.6°F (5.9°C) and a low of 35.4°F (1.9°C).Humidity
The months with the highest humidity are February and December, with an average relative humidity of 84%.Rainfall
The month with the most rainfall is December, when the rain falls for 18.1 days and typically aggregates up to 3.54" (90mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Mukilteo, in December, snow falls for 3.2 days, with typically accumulated 1.18" (30mm) of snow. Throughout the year, there are 16.3 snowfall days, and 10.08" (256mm) of snow is accumulated.Ocean temperature
In December, the average ocean temperature is 46.6°F (8.1°C).Note: Swimming in 46.6°F (8.1°C) poses a severe threat. Even short exposure to 55.4°F (13°C) is chilling, and going below 50°F (10°C) can cause breathing irregularities and intense cold shock, based on one's stamina.
Daylight
With an average of 8h and 30min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:38 am and sunset at 4:18 pm. On the last day of the month, sunrise is at 7:58 am and sunset at 4:26 pm PST.
Sunshine
The average sunshine in December is 4.5h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for average individuals.Note: A maximum high daily UV index of 2 during December translates into the following directions:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Take note! UV radiation from the Sun can double in intensity due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Mukilteo, WA
- Average high temperature in December: 42.6°F
The warmest month (with the highest average high temperature) is August (72.7°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in December: 35.4°F
The month with the highest average low temperature is August (54°F).
The coldest month (with the lowest average low temperature) is December (35.4°F).
Average pressure in December
Mukilteo, WA
- Average pressure in December: 30.08"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in December
Mukilteo, WA
- Average wind speed in December: 5.7mph
The windiest month (with the highest average wind speed) is November (6.2mph).
The calmest month (with the lowest average wind speed) is August (3.6mph).
Average humidity in December
Mukilteo, WA
- Average humidity in December: 84%
The months with the highest relative humidity are February and December (84%).
The month with the lowest relative humidity is July (72%).
Average rainfall in December
Mukilteo, WA
- Average rainfall in December: 3.54"
The wettest month (with the highest rainfall) is December (3.54").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in December
Mukilteo, WA
- Average rainfall days in December: 18.1 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in December
Mukilteo, WA
- Average snowfall in December: 1.18"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Mukilteo, WA
- Average snowfall days in December: 3.2 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in December
Mukilteo, WA
- Average sea temperature in December: 46.6°F
The best month for swimming (with the highest average sea temperature) is August (53.5°F).
The coldest month (with the lowest average sea temperature) is February (45.3°F).
Average daylight in December /
Average sunshine in December
Mukilteo, WA
- Average daylight in December: 8h and 30min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 4h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in December
Mukilteo, WA
- Average sunshine days in December: 10.7 days
The month with the most sunshine days is August (22.6 days).
The month with the least sunshine days is November (9.1 days).
Average UV index in December
Mukilteo, WA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Mukilteo, WA
- Average cloud cover in December: 54
The month with the most cloud cover is December (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in December
Mukilteo, WA
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
