December weather forecastBrook Hollow, MD
December
Weather in December
The first month of the winter, December, is also a frosty month in Brook Hollow, Maryland, with an average temperature ranging between max 43.5°F (6.4°C) and min 31.1°F (-0.5°C).Temperature
As December begins, there is a minor decrease in the average high-temperature, softly falling from a fresh 52.3°F (11.3°C) in November to a chilly 43.5°F (6.4°C). An average nighttime temperature of 31.1°F (-0.5°C) is noted during the month of December.Humidity
In Brook Hollow, the average relative humidity in December is 78%.Rainfall
In Brook Hollow, in December, it is raining for 10.4 days, with typically 2.24" (57mm) of accumulated precipitation. In Brook Hollow, during the entire year, the rain falls for 158.7 days and collects up to 30.91" (785mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Brook Hollow, in December, snow falls for 3.5 days, with typically accumulated 2.01" (51mm) of snow. In Brook Hollow, during the entire year, snow falls for 21.3 days and aggregates up to 13.31" (338mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 30min of daylight.On the first day of December, sunrise is at 7:09 am and sunset at 4:46 pm. On the last day of the month, sunrise is at 7:27 am and sunset at 4:55 pm EST.
Sunshine
In Brook Hollow, the average sunshine in December is 5.1h.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 estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for average individuals.Note: In December, a regular UV index of 2 translates into these guidelines:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Brook Hollow, MD
- Average high temperature in December: 43.5°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 (37.8°F).
- Average low temperature in December: 31.1°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (24.8°F).
Average pressure in December
Brook Hollow, 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
Brook Hollow, MD
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Brook Hollow, MD
- Average humidity in December: 78%
The months with the highest relative humidity are May and October (79%).
The months with the lowest relative humidity are April and July (74%).
Average rainfall in December
Brook Hollow, MD
- Average rainfall in December: 2.24"
The wettest month (with the highest rainfall) is August (3.82").
The driest month (with the least rainfall) is January (1.93").
Average rainfall days in December
Brook Hollow, MD
- Average rainfall days in December: 10.4 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in December
Brook Hollow, MD
- Average snowfall in December: 2.01"
The month with the highest snowfall is March (4.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Brook Hollow, MD
- Average snowfall days in December: 3.5 days
The month with the highest number of snowfall days is January (6.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Brook Hollow, 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 month with the least sunshine is February (Average sunshine: 4h and 54min).
Average sunshine days in December
Brook Hollow, MD
- Average sunshine days in December: 17.6 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is May (10.8 days).
Average UV index in December
Brook Hollow, 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
Brook Hollow, MD
- Average cloud cover in December: 45
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in December
Brook Hollow, 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).





