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 onset of December results in a decrease in the average high-temperature, receding from a frosty 49.8°F (9.9°C) in November to a cold 40.1°F (4.5°C). In December, Fullerton experiences a temperature dip to an average of 28.9°F (-1.7°C) at night.Humidity
The average relative humidity in December is 81%.Rainfall
In Fullerton, in December, during 9.2 rainfall days, 2.32" (59mm) of precipitation is typically accumulated. Throughout the year, there are 145.1 rainfall days, and 27.24" (692mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In December, it is snowing for 2.5 days. Throughout December, 2.28" (58mm) of snow is accumulated. Throughout the year, in Fullerton, there are 20.4 snowfall days, and 13.82" (351mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:06 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:25 am and sunset at 4:44 pm EST.
Sunshine
The average sunshine in December is 4.7h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: The daily maximum UV index of 2 in December interprets into the following advice:
Prolonged exposure to sunlight rarely troubles the majority, but constant protection is vital for babies, children, and fair-skinned people. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is December cold?
What is the average humidity in December?
How much does it rain in December?
How much 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?
How many hours of sunshine does Fullerton have in December?
When is the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Fullerton, PA
- Average high temperature in December: 40.1°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (34°F).
- Average low temperature in December: 28.9°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in December
Fullerton, PA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Fullerton, PA
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Fullerton, PA
- Average humidity in December: 81%
The month with the highest relative humidity is February (82%).
The months with the lowest relative humidity are April and July (76%).
Average rainfall in December
Fullerton, PA
- Average rainfall in December: 2.32"
The wettest month (with the highest rainfall) is July (3.03").
The driest month (with the least rainfall) is September (1.61").
Average rainfall days in December
Fullerton, PA
- Average rainfall days in December: 9.2 days
The month with the highest number of rainy days is May (16.9 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in December
Fullerton, PA
- Average snowfall in December: 2.28"
The month with the highest snowfall is March (4.37").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Fullerton, PA
- Average snowfall days in December: 2.5 days
The month with the highest number of snowfall days is February (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Fullerton, 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: 4h and 4min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days in December
Fullerton, PA
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is January (20.5 days).
The month with the least sunshine days is May (11.8 days).
Average UV index in December
Fullerton, PA
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in December
Fullerton, PA
- Average cloud cover in December: 51
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 34).
Average visibility in December
Fullerton, PA
- Average visibility in December: 5mi
The months with the highest visibility are April, July and November (6mi).
The months with the lowest visibility are January, February, March, May, June, August, September, October and December (5mi).
Fullerton, Pennsylvania, USA
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