December weather forecastCrownsville, MD
December
Weather in December
The first month of the winter, December, is still a chilly month in Crownsville, Maryland, with an average temperature fluctuating between 34.7°F (1.5°C) and 45.5°F (7.5°C).Temperature
December's arrival aligns with a minor decrease in average high-temperatures, from November's fresh 53.8°F (12.1°C) to a frosty 45.5°F (7.5°C). Throughout December, Crownsville's nights cool down to an average of 34.7°F (1.5°C).Humidity
In December, the average relative humidity is 75%.Rainfall
In Crownsville, in December, during 11.4 rainfall days, 2.83" (72mm) of precipitation is typically accumulated. In Crownsville, during the entire year, the rain falls for 155.7 days and collects up to 31.22" (793mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Crownsville, in December, snow falls for 2.4 days, with typically accumulated 0.63" (16mm) of snow. In Crownsville, during the entire year, snow falls for 14 days and aggregates up to 6.14" (156mm) of snow.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 4:44 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:54 pm EST.
Sunshine
The average sunshine in December is 5.2h.UV index
January, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: A typical high UV index of 2 in December suggests the following recommendations:
Babies, children, and individuals with sensitive skin should always have protection against extended sun exposure. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. On your guard! Snow's reflection can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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
Crownsville, 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).





