December weather forecastBlackrock Hills, MD
December
Weather in December
The first month of the winter, December, is still a chilly month in Blackrock Hills, Maryland, with an average temperature fluctuating between 31.8°F (-0.1°C) and 44.2°F (6.8°C).Temperature
In December, the meteorological conditions change slightly, with the average high-temperature moving from a fresh 53.1°F (11.7°C) in November to a frosty 44.2°F (6.8°C). Blackrock Hills, during December nights, observes an average temperature of 31.8°F (-0.1°C).Humidity
October and December, with an average relative humidity of 78%, are the most humid months.Rainfall
In Blackrock Hills, in December, during 10.5 rainfall days, 2.36" (60mm) of precipitation is typically accumulated. Throughout the year, there are 159.4 rainfall days, and 30.71" (780mm) of precipitation is accumulated.Snowfall
January through May, November and December are months with snowfall. In December, it is snowing for 3 days. Throughout December, 1.57" (40mm) of snow is accumulated. Throughout the year, there are 19.1 snowfall days, and 10.04" (255mm) 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 the month, sunrise is at 7:10 am and sunset at 4:46 pm. On the last day of December, sunrise is at 7:28 am and sunset at 4:56 pm EST.
Sunshine
In December, the average sunshine is 5.2h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Blackrock Hills. A UV Index reading of 2, and below, represents a minimal health hazard from exposure to the Sun's UV rays for ordinary individuals.Note: In December, the maximum UV index of 2 transforms into these recommendations:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. Guard yourself! Snow reflection 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
Blackrock Hills, MD
- Average high temperature in December: 44.2°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The month with the lowest average high temperature is January (38.8°F).
- Average low temperature in December: 31.8°F
The month with the highest average low temperature is July (66.9°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in December
Blackrock Hills, 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
Blackrock Hills, MD
- Average wind speed in December: 7mph
The windiest month (with the highest average wind speed) is March (7.8mph).
The calmest months (with the lowest average wind speed) are July and August (4.8mph).
Average humidity in December
Blackrock Hills, MD
- Average humidity in December: 78%
The months with the highest relative humidity are October and December (78%).
The month with the lowest relative humidity is July (72%).
Average rainfall in December
Blackrock Hills, MD
- Average rainfall in December: 2.36"
The wettest month (with the highest rainfall) is August (3.78").
The driest months (with the least rainfall) are January and February (1.97").
Average rainfall days in December
Blackrock Hills, MD
- Average rainfall days in December: 10.5 days
The month with the highest number of rainy days is May (17.5 days).
The months with the least rainy days are January and November (9.5 days).
Average snowfall in December
Blackrock Hills, MD
- Average snowfall in December: 1.57"
The month with the highest snowfall is March (2.83").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Blackrock Hills, MD
- Average snowfall days in December: 3 days
The months with the highest number of snowfall days are January and February (5.8 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
Blackrock Hills, 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 January (Average sunshine: 5h and 0min).
Average sunshine days in December
Blackrock Hills, MD
- Average sunshine days in December: 18.2 days
The month with the most sunshine days is November (19 days).
The month with the least sunshine days is July (11.3 days).
Average UV index in December
Blackrock Hills, 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
Blackrock Hills, 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
Blackrock Hills, 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).
