December weather forecastJefferson, MD
December
Weather in December
The first month of the winter, December, is also a frosty month in Jefferson, Maryland, with an average temperature varying between 33.1°F (0.6°C) and 45.5°F (7.5°C).Temperature
A decrease in the average high-temperature is observed during December, shifting from a cool 54.5°F (12.5°C) in November to a chilly 45.5°F (7.5°C). In Jefferson, the December nights cool down to an average low of 33.1°F (0.6°C).Humidity
In December, the average relative humidity is 76%.Rainfall
In Jefferson, in December, it is raining for 10.8 days, with typically 2.68" (68mm) of accumulated precipitation. Throughout the year, there are 161.2 rainfall days, and 31.54" (801mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In Jefferson, during December, snow falls for 2.6 days and regularly aggregates up to 1.73" (44mm) of snow. In Jefferson, during the entire year, snow falls for 16.1 days and aggregates up to 10.39" (264mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:11 am and sunset at 4:47 pm. On the last day of December, sunrise is at 7:29 am and sunset at 4:56 pm EST.
Sunshine
January, February and December, with an average of 5.2h of sunshine, are months with the least sunshine.UV index
January, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index reading of 2, and below, represents a minimal health hazard from exposure to the Sun's UV rays for the average person.Note: In December, a regular UV index of 2 translates into these guidelines:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Stay alert! Snow's reflective properties can almost double the UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Jefferson, MD
- Average high temperature in December: 45.5°F
The warmest month (with the highest average high temperature) is July (87.6°F).
The month with the lowest average high temperature is January (40.5°F).
- Average low temperature in December: 33.1°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (27.1°F).
Average pressure in December
Jefferson, 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
Jefferson, MD
- Average wind speed in December: 6.6mph
The windiest month (with the highest average wind speed) is March (7.6mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Jefferson, MD
- Average humidity in December: 76%
The month with the highest relative humidity is October (77%).
The months with the lowest relative humidity are April and July (71%).
Average rainfall in December
Jefferson, MD
- Average rainfall in December: 2.68"
The wettest month (with the highest rainfall) is August (3.78").
The driest month (with the least rainfall) is January (2.05").
Average rainfall days in December
Jefferson, MD
- Average rainfall days in December: 10.8 days
The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is November (8.9 days).
Average snowfall in December
Jefferson, MD
- Average snowfall in December: 1.73"
The month with the highest snowfall is January (3.31").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Jefferson, MD
- Average snowfall days in December: 2.6 days
The month with the highest number of snowfall days is January (4.9 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
Jefferson, MD
- Average daylight in December: 9h and 24min
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 24min).
- Average sunshine in December: 5h and 12min
The month with the most sunshine is July (Average sunshine: 10h and 54min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 12min).
Average sunshine days in December
Jefferson, MD
- Average sunshine days in December: 17.4 days
The month with the most sunshine days is November (19.2 days).
The month with the least sunshine days is July (10.9 days).
Average UV index in December
Jefferson, 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, November and December (UV index 2).
Average cloud cover in December
Jefferson, MD
- Average cloud cover in December: 44
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
Jefferson, 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).
