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 implies a soft temperature shift, with average high-temperatures reducing from November's moderate 56.7°F (13.7°C) to a frosty 49.1°F (9.5°C). Nighttime temperatures in Rockville consistently average an icy 34.9°F (1.6°C) during December.Humidity
With an average relative humidity of 78%, December is the most humid month.Rainfall
In Rockville, Virginia, in December, it is raining for 10.1 days, with typically 1.93" (49mm) of accumulated precipitation. In Rockville, during the entire year, the rain falls for 151.1 days and collects up to 26.22" (666mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In December, in Rockville, it is snowing for 1.5 days. Throughout December, 1.5" (38mm) of snow is accumulated. Throughout the year, in Rockville, Virginia, there are 10.5 snowfall days, and 6.42" (163mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 36min of daylight.On the first day of the month, sunrise is at 7:07 am and sunset at 4:52 pm. On the last day of December, sunrise is at 7:25 am and sunset at 5:02 pm EST.
Sunshine
The month with the least sunshine in Rockville is December, with an average of 5.2h of sunshine.UV index
The months with the lowest UV index are January, February and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a minimal health hazard from exposure to the Sun's UV radiation for the average person.Note: A maximum daily UV index of 2 during December morphs into the following directions:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Frequently asked questions
What is the usual temperature for Rockville in December?
What is the most humid month in Rockville?
What is the average humidity in December in Rockville?
How much does it rain in Rockville in December?
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?
What time are sunrise and sunset in December in Rockville?
What is the month with the least sunshine in Rockville?
How many hours of sunshine does Rockville have in December?
What is the month with the lowest UV index in Rockville?
What is the UV index reading in December in Rockville?
Average temperature in December
Rockville, VA
- Average high temperature in December: 49.1°F
The warmest month (with the highest average high temperature) is July (90.7°F).
The month with the lowest average high temperature is January (44.2°F).
- Average low temperature in December: 34.9°F
The month with the highest average low temperature is July (69.6°F).
The coldest month (with the lowest average low temperature) is January (29.5°F).
Average pressure in December
Rockville, VA
- Average pressure in December: 30.12"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, VA
- Average wind speed in December: 6mph
The windiest month (with the highest average wind speed) is April (7.4mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in December
Rockville, VA
- Average humidity in December: 78%
The month with the highest relative humidity is December (78%).
The month with the lowest relative humidity is July (68%).
Average rainfall in December
Rockville, VA
- Average rainfall in December: 1.93"
The wettest month (with the highest rainfall) is August (2.72").
The driest month (with the least rainfall) is September (1.65").
Average rainfall days in December
Rockville, VA
- Average rainfall days in December: 10.1 days
The month with the highest number of rainy days is May (16.6 days).
The month with the least rainy days is November (8.8 days).
Average snowfall in December
Rockville, VA
- Average snowfall in December: 1.5"
The month with the highest snowfall is February (1.77").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Rockville, VA
- Average snowfall days in December: 1.5 days
The month with the highest number of snowfall days is February (3.5 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, VA
- Average daylight in December: 9h and 4min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 5h and 12min).
Average sunshine days in December
Rockville, VA
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is May (11.9 days).
Average UV index in December
Rockville, VA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in December
Rockville, VA
- Average cloud cover in December: 44
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in December
Rockville, VA
- 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, Virginia, USA
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