December weather forecastChantilly, VA
December
Weather in December
The first month of the winter, December, is also a frosty month in Chantilly, Virginia, with temperature in the range of an average low of 32.2°F (0.1°C) and an average high of 45.3°F (7.4°C).Temperature
The beginning of December brings a slight decrease in the average high-temperature, transitioning from a fresh 53.6°F (12°C) in November to a frosty 45.3°F (7.4°C). Chantilly records a mean low-temperature of 32.2°F (0.1°C) in December.Humidity
October and December, with an average relative humidity of 77%, are the most humid months.Rainfall
In Chantilly, in December, it is raining for 10.4 days, with typically 2.68" (68mm) of accumulated precipitation. In Chantilly, during the entire year, the rain falls for 156 days and collects up to 31.18" (792mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Chantilly, in December, snow falls for 2.7 days, with typically accumulated 1.97" (50mm) of snow. In Chantilly, during the entire year, snow falls for 16.8 days and aggregates up to 12.48" (317mm) 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 4:48 pm. On the last day of December, sunrise is at 7:28 am and sunset at 4:57 pm EST.
Sunshine
The months with the least sunshine are January, February and December, with an average of 5.1h of 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 of 2, and less, symbolizes a low health risk from exposure to the Sun's UV radiation for average individuals.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Although prolonged sun exposure does not typically bother most people, children, babies, and those with sensitive skin should always have protection. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Chantilly, VA
- Average high temperature in December: 45.3°F
The warmest month (with the highest average high temperature) is July (88.2°F).
The month with the lowest average high temperature is January (39.7°F).
- Average low temperature in December: 32.2°F
The month with the highest average low temperature is July (67.3°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in December
Chantilly, VA
- 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
Chantilly, VA
- Average wind speed in December: 6.5mph
The windiest months (with the highest average wind speed) are March and April (7.3mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in December
Chantilly, VA
- Average humidity in December: 77%
The months with the highest relative humidity are October and December (77%).
The month with the lowest relative humidity is July (71%).
Average rainfall in December
Chantilly, VA
- Average rainfall in December: 2.68"
The wettest month (with the highest rainfall) is August (3.74").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Chantilly, VA
- Average rainfall days in December: 10.4 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in December
Chantilly, VA
- Average snowfall in December: 1.97"
The month with the highest snowfall is January (3.58").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Chantilly, VA
- Average snowfall days in December: 2.7 days
The month with the highest number of snowfall days is February (5.3 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
Chantilly, VA
- 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 42min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 6min).
Average sunshine days in December
Chantilly, VA
- Average sunshine days in December: 17.8 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is July (12.1 days).
Average UV index in December
Chantilly, VA
- 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
Chantilly, VA
- Average cloud cover in December: 46
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in December
Chantilly, VA
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and May (5mi).
