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
The shift from November to December involves a decrease in the average high-temperature, from a chilly 46.4°F (8°C) to a wintry 36.5°F (2.5°C). Twin Rocks cools down to an average low-temperature of 26.6°F (-3°C) throughout the month of December.Humidity
In Twin Rocks, the average relative humidity in December is 85%.Rainfall
In Twin Rocks, Pennsylvania, in December, during 10.8 rainfall days, 3.07" (78mm) of precipitation is typically accumulated. Throughout the year, there are 169.1 rainfall days, and 32.6" (828mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Twin Rocks, Pennsylvania, in December, snow falls for 12.4 days, with typically accumulated 6.38" (162mm) of snow. In Twin Rocks, during the entire year, snow falls for 65.6 days and aggregates up to 33.54" (852mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:20 am and sunset at 4:49 pm. On the last day of the month, sunrise is at 7:38 am and sunset at 4:58 pm EST.
Sunshine
In Twin Rocks, the average sunshine in December is 3.3h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index, 1 in December, converts into the following recommendations:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. To cut down UV radiation exposure by about half, sport a wide-brim hat. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in December?
What is the average humidity in December?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When is the sunrise / sunset in December in Twin Rocks?
How many hours of sunshine does Twin Rocks have in December?
What is the month with the lowest UV index?
What is the UV index reading in December?
Average temperature in December
Twin Rocks, PA
- Average high temperature in December: 36.5°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in December: 26.6°F
The month with the highest average low temperature is July (59°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in December
Twin Rocks, PA
- 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
Twin Rocks, PA
- Average wind speed in December: 9.4mph
The windiest month (with the highest average wind speed) is January (10.1mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).
Average humidity in December
Twin Rocks, PA
- Average humidity in December: 85%
The months with the highest relative humidity are January and February (86%).
The months with the lowest relative humidity are April and July (78%).
Average rainfall in December
Twin Rocks, PA
- Average rainfall in December: 3.07"
The wettest month (with the highest rainfall) is May (3.58").
The driest month (with the least rainfall) is November (1.85").
Average rainfall days in December
Twin Rocks, PA
- Average rainfall days in December: 10.8 days
The month with the highest number of rainy days is May (20.7 days).
The month with the least rainy days is February (9.3 days).
Average snowfall in December
Twin Rocks, PA
- Average snowfall in December: 6.38"
The month with the highest snowfall is January (8.27").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Twin Rocks, PA
- Average snowfall days in December: 12.4 days
The month with the highest number of snowfall days is January (17.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Twin Rocks, PA
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 3h and 2min
The months with the most sunshine are July and August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 2h and 54min).
Average sunshine days in December
Twin Rocks, PA
- Average sunshine days in December: 9.8 days
The month with the most sunshine days is November (14.8 days).
The month with the least sunshine days is January (7.5 days).
Average UV index in December
Twin Rocks, PA
- Average UV index in December: 1
The months with the highest UV index are May, June, July and August (UV index 5).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Twin Rocks, PA
- Average cloud cover in December: 68
The month with the most cloud cover is January (Cloud cover 72).
The months with the least cloud cover are July and August (Cloud cover 39).
Average visibility in December
Twin Rocks, PA
- Average visibility in December: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January and February (4mi).
Twin Rocks, Pennsylvania, USA
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