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 arrival comes with a mild decrease in the average high-temperature, moving subtly from a cool 54.5°F (12.5°C) in November to a frosty 46.6°F (8.1°C). Rio witnesses a consistent average low-temperature of 31.8°F (-0.1°C) throughout December.Humidity
The months with the highest humidity in Rio are May, September, October and December, with an average relative humidity of 76%.Rainfall
In December, in Rio, the rain falls for 9.2 days. Throughout December, 2.36" (60mm) of precipitation is accumulated. Throughout the year, in Rio, there are 155.9 rainfall days, and 27.99" (711mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In Rio, in December, snow falls for 1.9 days, with typically accumulated 1.38" (35mm) of snow. In Rio, during the entire year, snow falls for 14.6 days and aggregates up to 10.43" (265mm) of snow.Daylight
With an average of 9h and 36min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:11 am and sunset at 4:54 pm. On the last day of December, in Rio, sunrise is at 7:29 am and sunset at 5:04 pm EST.
Sunshine
The months with the least sunshine are January and December, with an average of 5.4h of sunshine.UV index
The months with the lowest UV index in Rio are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Boost your sun resistance with garments that are densely woven yet spacious. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Frequently asked questions
What are the temperatures in Rio in December?
What is the most humid month in Rio?
What is the average humidity in December in Rio?
How many days does it rain in December in Rio?
How much does it snow in Rio in December?
What is the month with the shortest days in Rio?
What is the average length of the day in December in Rio?
When are sunrise and sunset in December in Rio?
What are the months with the least sunshine in Rio?
How long on average sun shines in December in Rio?
When is the lowest UV index in Rio?
How high is the UV index in December in Rio?
Average temperature in December
Rio, VA
- Average high temperature in December: 46.6°F
The warmest month (with the highest average high temperature) is July (88.2°F).
The month with the lowest average high temperature is January (41.5°F).
- Average low temperature in December: 31.8°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in December
Rio, 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 (29.96"Hg).
Average wind speed in December
Rio, VA
- Average wind speed in December: 5.2mph
The windiest month (with the highest average wind speed) is April (6.3mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in December
Rio, VA
- Average humidity in December: 76%
The months with the highest relative humidity are May, September, October and December (76%).
The month with the lowest relative humidity is July (71%).
Average rainfall in December
Rio, VA
- Average rainfall in December: 2.36"
The wettest months (with the highest rainfall) are April and May (2.91").
The driest month (with the least rainfall) is January (1.69").
Average rainfall days in December
Rio, VA
- Average rainfall days in December: 9.2 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is November (8.9 days).
Average snowfall in December
Rio, VA
- Average snowfall in December: 1.38"
The month with the highest snowfall is March (3.07").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Rio, VA
- Average snowfall days in December: 1.9 days
The month with the highest number of snowfall days is January (4.6 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
Rio, VA
- Average daylight in December: 9h and 4min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The months with the least sunshine are January and December (Average sunshine: 5h and 24min).
Average sunshine days in December
Rio, VA
- Average sunshine days in December: 19.9 days
The month with the most sunshine days is December (19.9 days).
The month with the least sunshine days is May (11.4 days).
Average UV index in December
Rio, VA
- 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
Rio, VA
- Average cloud cover in December: 42
The month with the most cloud cover is March (Cloud cover 45).
The months with the least cloud cover are June and July (Cloud cover 31).
Average visibility in December
Rio, VA
- Average visibility in December: 5mi
The months with the highest visibility are February, March, April, June, July, August and November (6mi).
The months with the lowest visibility are January, May, September, October and December (5mi).
Rio, Virginia, USA
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