December weather forecastRenton, WA
December
Weather in December
December in Renton marks the on-set of winter with lower temperatures and decreased sunlight hours. For those who enjoy colder climates, this is the ideal time, with temperatures moving between 43.3°F (6.3°C) and 34.2°F (1.2°C). The short daylight span of 8.5 hours and heightened cloudiness at 58% render a typical winter atmosphere. Despite the cold narrative of December, there is almost no snowfall, just a trace amount. As the month progresses, higher pressure readings and robust winds pervade, bringing a sense of the cold winter blues to end the year.Temperature
In Renton, Washington, the month of December is known for its lowest average temperatures, reaching a high of 43.3°F (6.3°C) and a low of 34.2°F (1.2°C).Humidity
The months with the highest humidity are January and December, with an average relative humidity of 85%.Rainfall
The month with the most rainfall is December, when the rain falls for 11.2 days and typically aggregates up to 1.34" (34mm) of precipitation.Snowfall
January through March, November and December are months with snowfall. In Renton, in December, during 1.1 snowfall days, 0.04" (1mm) of snow is typically accumulated. Throughout the year, in Renton, Washington, there are 4.9 snowfall days, and 1.18" (30mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 8h and 30min of daylight.On the first day of December, sunrise is at 7:36 am and sunset at 4:19 pm. On the last day of the month, sunrise is at 7:56 am and sunset at 4:28 pm PST.
Sunshine
The months with the least sunshine are January and December, with an average of 4.1h of sunshine.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 value of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for average individuals.Note: In December, the maximum UV index of 2 transforms into these recommendations:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Renton, WA
- Average high temperature in December: 43.3°F
The warmest months (with the highest average high temperature) are July and August (77.4°F).
The month with the lowest average high temperature is December (43.3°F).
- Average low temperature in December: 34.2°F
The month with the highest average low temperature is August (53.6°F).
The coldest month (with the lowest average low temperature) is December (34.2°F).
Average pressure in December
Renton, WA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in December
Renton, WA
- Average wind speed in December: 4.6mph
The windiest month (with the highest average wind speed) is March (5.2mph).
The calmest month (with the lowest average wind speed) is August (3.6mph).
Average humidity in December
Renton, WA
- Average humidity in December: 85%
The months with the highest relative humidity are January and December (85%).
The months with the lowest relative humidity are July and August (68%).
Average rainfall in December
Renton, WA
- Average rainfall in December: 1.34"
The wettest month (with the highest rainfall) is December (1.34").
The driest month (with the least rainfall) is July (0.12").
Average rainfall days in December
Renton, WA
- Average rainfall days in December: 11.2 days
The month with the highest number of rainy days is March (11.9 days).
The month with the least rainy days is August (3 days).
Average snowfall in December
Renton, WA
- Average snowfall in December: 0.04"
The month with the highest snowfall is February (0.63").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Renton, WA
- Average snowfall days in December: 1.1 days
The month with the highest number of snowfall days is February (1.7 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Renton, WA
- Average daylight in December: 8h and 30min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 4h and 6min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are January and December (Average sunshine: 4h and 6min).
Average sunshine days in December
Renton, WA
- Average sunshine days in December: 17.1 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is February (15.5 days).
Average UV index in December
Renton, WA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Renton, WA
- Average cloud cover in December: 58
The months with the most cloud cover are January and December (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Renton, WA
- Average visibility in December: 5mi
The months with the highest visibility are June, July, August and September (6mi).
The months with the lowest visibility are January, February, March, April, May, October, November and December (5mi).
