Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December's onset corresponds with a subtle shift in the average high-temperature, slightly moving from a cool 53.4°F (11.9°C) in November to a chilly 45.3°F (7.4°C). During December, Rockville experiences an average low-temperature of 32.9°F (0.5°C) at night.Humidity
December is the most humid month, with an average relative humidity of 77%.Rainfall
In Rockville, in December, during 9.9 rainfall days, 2.44" (62mm) of precipitation is typically accumulated. In Rockville, during the entire year, the rain falls for 156.4 days and collects up to 30.79" (782mm) of precipitation.Snowfall
Months with snowfall in Rockville are January through April, November and December. In December, it is snowing for 3.2 days. Throughout December, 1.42" (36mm) of snow is accumulated. Throughout the year, in Rockville, Maryland, there are 17.7 snowfall days, and 9.92" (252mm) 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 7:09 am and sunset at 4:46 pm. On the last day of December, in Rockville, sunrise is at 7:27 am and sunset at 4:56 pm EST.
Sunshine
The months with the least sunshine are January, February and December, with an average of 5.1h of sunshine.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: The maximum daily UV index of 2 in December interprets into the following recommendations:
While many people can endure lengthy sun exposure, it remains imperative to safeguard babies, children, and fair-skinned individuals. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Alert! The snow's reflection can amplify the UV radiation of the Sun nearly twice.
Frequently asked questions
What is the average December temperature in Rockville?
What is the most humid month in Rockville?
What is the average humidity in December in Rockville?
How many days does it rain in December in Rockville?
How many days does it snow in December in Rockville?
What is the month with the shortest days in Rockville?
How many hours of daylight does Rockville have in December?
When is the sunrise / sunset in December in Rockville?
What is the month with the least sunshine in Rockville?
How long on average sun shines in December in Rockville?
When is the lowest UV index in Rockville?
How high is the UV index in December in Rockville?
Average temperature in December
Rockville, MD
- Average high temperature in December: 45.3°F
The warmest month (with the highest average high temperature) is July (87.1°F).
The month with the lowest average high temperature is January (39°F).
- Average low temperature in December: 32.9°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).
Average pressure in December
Rockville, 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
Rockville, MD
- Average wind speed in December: 7mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Rockville, MD
- Average humidity in December: 77%
The month with the highest relative humidity is December (77%).
The month with the lowest relative humidity is July (70%).
Average rainfall in December
Rockville, MD
- Average rainfall in December: 2.44"
The wettest month (with the highest rainfall) is August (3.9").
The driest month (with the least rainfall) is January (1.97").
Average rainfall days in December
Rockville, MD
- Average rainfall days in December: 9.9 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is November (9.2 days).
Average snowfall in December
Rockville, MD
- Average snowfall in December: 1.42"
The month with the highest snowfall is March (3.03").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Rockville, MD
- Average snowfall days in December: 3.2 days
The months with the highest number of snowfall days are January and February (5.3 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
Rockville, MD
- Average daylight in December: 9h and 3min
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 1min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 6min).
Average sunshine days in December
Rockville, MD
- Average sunshine days in December: 17.7 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is July (12 days).
Average UV index in December
Rockville, 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
Rockville, 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
Rockville, 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).
Rockville, Maryland, USA
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