December weather forecastGaithersburg, MD
December
Weather in December
December's chill becomes more pronounced, ushering in the true winter spirit with temperatures ranging from 32.2°F (0.1°C) to 44.2°F (6.8°C). Gaithersburg experiences a colder and festive atmosphere during this month. Snowfall makes a comeback after a long absence since early spring. Despite being the coldest month, December has its charm, courtesy of the holiday spirit, winter markets, and snow-covered scenery. This makes it the perfect time for snuggling indoors and partaking in festive cheer.Temperature
The start of December signals a gentle decrease in the average high-temperature, transitioning from a cool 53.1°F (11.7°C) in November to a chilly 44.2°F (6.8°C). Throughout the month of December, the average temperature dips to a cold 32.2°F (0.1°C) at night.Humidity
The months with the highest humidity are May, October and December, with an average relative humidity of 77%.Rainfall
In Gaithersburg, Maryland, during December, the rain falls for 10.5 days and regularly aggregates up to 2.09" (53mm) of precipitation. Throughout the year, there are 154.8 rainfall days, and 29.09" (739mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, November and December. In Gaithersburg, in December, snow falls for 2.5 days, with typically accumulated 1.38" (35mm) of snow. In Gaithersburg, during the entire year, snow falls for 16.7 days and aggregates up to 9.76" (248mm) 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 7:09 am and sunset at 4:46 pm. On the last day of December, sunrise is at 7:27 am and sunset at 4:56 pm EST.
Sunshine
January, February and December, with an average of 5.1h of sunshine, are months with the least sunshine.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The UV index of 2 during December leads to these advisories:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Experience reduced UV exposure by about half when donning a wide-brim hat. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Gaithersburg, MD
- Average high temperature in December: 44.2°F
The warmest month (with the highest average high temperature) is July (86.9°F).
The month with the lowest average high temperature is January (38.8°F).
- Average low temperature in December: 32.2°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in December
Gaithersburg, 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 (29.95"Hg).
Average wind speed in December
Gaithersburg, MD
- Average wind speed in December: 7.1mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in December
Gaithersburg, MD
- Average humidity in December: 77%
The months with the highest relative humidity are May, October and December (77%).
The month with the lowest relative humidity is July (72%).
Average rainfall in December
Gaithersburg, MD
- Average rainfall in December: 2.09"
The wettest month (with the highest rainfall) is August (3.82").
The driest month (with the least rainfall) is January (1.73").
Average rainfall days in December
Gaithersburg, MD
- Average rainfall days in December: 10.5 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (8.7 days).
Average snowfall in December
Gaithersburg, MD
- Average snowfall in December: 1.38"
The month with the highest snowfall is January (2.76").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Gaithersburg, MD
- Average snowfall days in December: 2.5 days
The month with the highest number of snowfall days is February (5.3 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Gaithersburg, 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 48min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 6min).
Average sunshine days in December
Gaithersburg, MD
- Average sunshine days in December: 18.4 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is July (11.5 days).
Average UV index in December
Gaithersburg, 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, February, November and December (UV index 2).
Average cloud cover in December
Gaithersburg, 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 30).
Average visibility in December
Gaithersburg, MD
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).





