December weather forecastMount Rainier, MD
December
Weather in December
December marks the official onset of winter in Mount Rainier, characterized by colder temperatures and increased precipitation compared to the preceding month. The city witnesses a dip in the temperature scale, ranging between 34.3°F (1.3°C) and 45.5°F (7.5°C). As the year draws to a close, it brings about the shortest daylight hours and fewest sunshine days, a reflection of the seasonal change. Although snowfall slightly increasess in December, the city won’t see a comparable level until the subsequent January. Consequently, December weather helps to usher in the new year under a canopy of clouds and a blanket of white snow.Temperature
The move into December in Mount Rainier indicates a slight reduction in the average high-temperature, down from November's cool 54.1°F (12.3°C) to a chilly 45.5°F (7.5°C). In December, Mount Rainier reports a consistent average low-temperature of 34.3°F (1.3°C) during the nights.Humidity
May, October and December, with an average relative humidity of 76%, are the most humid months.Rainfall
In December, the rain falls for 9.8 days. Throughout December, 2.6" (66mm) of precipitation is accumulated. Throughout the year, there are 157.9 rainfall days, and 31.14" (791mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April and December. December is the first month it typically snows. Throughout December, in the average 2.4 snowfall days, it receives 0.67" (17mm) of snow. In Mount Rainier, during the entire year, snow falls for 13.5 days and aggregates up to 7.2" (183mm) of snow.Daylight
With an average of 9h and 30min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:08 am and sunset at 4:46 pm. On the last day of December, sunrise is at 7:26 am and sunset at 4:55 pm EST.
Sunshine
In Mount Rainier, the average sunshine in December is 5.1h.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 2. A UV Index value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Most individuals face no major issues with lengthy exposure to the sun, but children, infants, and individuals with fair skin always require protection. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Mount Rainier, MD
- Average high temperature in December: 45.5°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.9°F).
- Average low temperature in December: 34.3°F
The month with the highest average low temperature is July (70°F).
The coldest month (with the lowest average low temperature) is January (27.7°F).
Average pressure in December
Mount Rainier, MD
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Mount Rainier, MD
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).
Average humidity in December
Mount Rainier, MD
- Average humidity in December: 76%
The months with the highest relative humidity are May, October and December (76%).
The months with the lowest relative humidity are April and July (71%).
Average rainfall in December
Mount Rainier, MD
- Average rainfall in December: 2.6"
The wettest month (with the highest rainfall) is August (3.58").
The driest month (with the least rainfall) is January (2.01").
Average rainfall days in December
Mount Rainier, MD
- Average rainfall days in December: 9.8 days
The month with the highest number of rainy days is May (17.9 days).
The month with the least rainy days is November (9 days).
Average snowfall in December
Mount Rainier, MD
- Average snowfall in December: 0.67"
The month with the highest snowfall is January (2.6").
The months with the least snowfall are May, June, July, August, September, October and November (0").
Average snowfall days in December
Mount Rainier, MD
- Average snowfall days in December: 2.4 days
The month with the highest number of snowfall days is January (4.1 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
Mount Rainier, MD
- Average daylight in December: 9h and 30min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in December: 5h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 54min).
The month with the least sunshine is February (Average sunshine: 5h and 0min).
Average sunshine days in December
Mount Rainier, MD
- Average sunshine days in December: 18.1 days
The month with the most sunshine days is November (19.1 days).
The month with the least sunshine days is May (11.8 days).
Average UV index in December
Mount Rainier, MD
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in December
Mount Rainier, MD
- Average cloud cover in December: 45
The month with the most cloud cover is March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 29).
Average visibility in December
Mount Rainier, MD
- 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).
