December weather forecastWillowbrook, MD
December
Weather in December
December, the first month of the winter in Willowbrook, is also a frosty month, with an average temperature varying between 34.7°F (1.5°C) and 45.5°F (7.5°C).Temperature
December's onset introduces a mild reduction in the average high-temperature, from a fresh 53.8°F (12.1°C) in November to a chilly 45.5°F (7.5°C). Throughout December nights, Willowbrook experiences a consistent temperature average of 34.7°F (1.5°C).Humidity
In December, the average relative humidity in Willowbrook is 75%.Rainfall
In Willowbrook, Maryland, during December, the rain falls for 11.4 days and regularly aggregates up to 2.83" (72mm) of precipitation. Throughout the year, there are 155.7 rainfall days, and 31.22" (793mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 2.4 days. Throughout December, 0.63" (16mm) of snow is accumulated. Throughout the year, there are 14 snowfall days, and 6.14" (156mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 30min of daylight.On the first day of December, sunrise is at 7:06 am and sunset at 4:43 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:53 pm EST.
Sunshine
The average sunshine in December is 5.2h.UV index
The months with the lowest UV index are January, November and December, with an average maximum UV index of 2. A UV Index value of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: The daily maximum UV index of 2 in December interprets into the following advice:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. To protect against the Sun's most potent rays, avoid direct exposure around midday. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Willowbrook, MD
- Average high temperature in December: 45.5°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in December: 34.7°F
The month with the highest average low temperature is July (70.7°F).
The coldest month (with the lowest average low temperature) is January (28.4°F).
Average pressure in December
Willowbrook, 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
Willowbrook, MD
- Average wind speed in December: 8.6mph
The windiest month (with the highest average wind speed) is March (9.4mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity in December
Willowbrook, MD
- Average humidity in December: 75%
The month with the highest relative humidity is May (78%).
The months with the lowest relative humidity are January, March, April and November (72%).
Average rainfall in December
Willowbrook, MD
- Average rainfall in December: 2.83"
The wettest month (with the highest rainfall) is August (3.54").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Willowbrook, MD
- Average rainfall days in December: 11.4 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is November (9.4 days).
Average snowfall in December
Willowbrook, MD
- Average snowfall in December: 0.63"
The month with the highest snowfall is January (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Willowbrook, MD
- Average snowfall days in December: 2.4 days
The month with the highest number of snowfall days is January (4.4 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
Willowbrook, 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 12min
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 6min).
Average sunshine days in December
Willowbrook, MD
- Average sunshine days in December: 16.9 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is May (10.8 days).
Average UV index in December
Willowbrook, 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
Willowbrook, MD
- Average cloud cover in December: 44
The months with the most cloud cover are February and March (Cloud cover 45).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in December
Willowbrook, 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).





