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
Williamson's weather in December involves a decrease in the average high-temperature, moving down from November's cool 50.5°F (10.3°C) to an icy 41.2°F (5.1°C). Williamson observes an average low-temperature of 28.9°F (-1.7°C) during December nights.Humidity
The months with the highest humidity are February, May, October and December, with an average relative humidity of 79%.Rainfall
In Williamson, in December, during 10.3 rainfall days, 2.01" (51mm) of precipitation is typically accumulated. Throughout the year, in Williamson, Pennsylvania, there are 161.8 rainfall days, and 28.07" (713mm) of precipitation is accumulated.Snowfall
Months with snowfall in Williamson are January through April, October through December. In December, in Williamson, it is snowing for 4.7 days. Throughout December, 2.13" (54mm) of snow is accumulated. In Williamson, during the entire year, snow falls for 26.6 days and aggregates up to 14.69" (373mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of December in Williamson, sunrise is at 7:14 am and sunset at 4:46 pm. On the last day of the month, sunrise is at 7:32 am and sunset at 4:56 pm EST.
Sunshine
In December, the average sunshine is 4.8h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Williamson. A UV Index estimate of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: During December, 2 as the daily maximum UV index converts into the following advice:
Long-term sun exposure is typically not a concern for most. However, those with sensitive skin, infants, and children must always have protection. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays. Consider carefully! The reflective quality of snow can almost double the intensity of the Sun's UV radiation.
Frequently asked questions
Is December cold in Williamson?
What are the most humid months in Williamson?
What is the average humidity in December in Williamson?
How many days does it rain in December in Williamson?
How much does it snow in Williamson in December?
What is the month with the shortest days in Williamson?
How many hours of daylight does Williamson have in December?
What time are sunrise and sunset in December in Williamson?
How many hours of sunshine does Williamson have in December?
What is the month with the lowest UV index in Williamson?
What is the UV index reading in December in Williamson?
Average temperature in December
Williamson, PA
- Average high temperature in December: 41.2°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in December: 28.9°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (22.5°F).
Average pressure in December
Williamson, 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
Williamson, PA
- Average wind speed in December: 7mph
The windiest month (with the highest average wind speed) is January (7.7mph).
The calmest months (with the lowest average wind speed) are July and August (4.5mph).
Average humidity in December
Williamson, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February, May, October and December (79%).
The months with the lowest relative humidity are April and July (75%).
Average rainfall in December
Williamson, PA
- Average rainfall in December: 2.01"
The wettest month (with the highest rainfall) is May (3.15").
The driest month (with the least rainfall) is January (1.85").
Average rainfall days in December
Williamson, PA
- Average rainfall days in December: 10.3 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is November (9 days).
Average snowfall in December
Williamson, PA
- Average snowfall in December: 2.13"
The month with the highest snowfall is January (4.53").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Williamson, PA
- Average snowfall days in December: 4.7 days
The month with the highest number of snowfall days is January (8.1 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Williamson, 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 24min).
- Average sunshine in December: 4h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Williamson, PA
- Average sunshine days in December: 17.1 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10.4 days).
Average UV index in December
Williamson, PA
- Average UV index in December: 2
The months with the highest UV index are May, June and July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Williamson, PA
- Average cloud cover in December: 50
The months with the most cloud cover are January, February and December (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in December
Williamson, PA
- Average visibility in December: 5mi
The months with the highest visibility are April, June, July, August and November (6mi).
The months with the lowest visibility are January, February, March, May, September, October and December (5mi).
Williamson, Pennsylvania, USA
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