December weather forecastWilliamstown, WV
December
Weather in December
December witnesses a significant drop in temperatures, tumbling to the frigid range of 30.4°F (-0.9°C) to 41.7°F (5.4°C). Snowfall makes a comeback with an average accumulation of 1.46" (37mm). The decrease in daylight hours to 9.4, the shortest in the year, indicates the arrival of winter. In addition, atmospheric pressure reaches 30.13" (765mm), one of the highest readings of the year. As the year wraps up, anticipation for the New Year's weather commences.Temperature
In Williamstown, entering December brings a temperature decrement, reducing from November's fresh 51.1°F (10.6°C) to a wintry 41.7°F (5.4°C). Williamstown's nights in December cool down to an average low-temperature of 30.4°F (-0.9°C).Humidity
In December, the average relative humidity in Williamstown is 82%.Rainfall
In Williamstown, West Virginia, in December, it is raining for 11.3 days, with typically 2.24" (57mm) of accumulated precipitation. In Williamstown, during the entire year, the rain falls for 156.1 days and collects up to 24.8" (630mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In December, in Williamstown, it is snowing for 5.4 days. Throughout December, 1.46" (37mm) of snow is accumulated. Throughout the year, there are 31.3 snowfall days, and 9.37" (238mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:27 am and sunset at 5:02 pm. On the last day of December, in Williamstown, sunrise is at 7:45 am and sunset at 5:12 pm EST.
Sunshine
In Williamstown, West Virginia, the average sunshine in December is 3.8h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Williamstown. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's UV radiation for the average person.Note: In December, a daily UV index of 2 turns into the following recommendations:
Extended time in the sun generally does not harm most, but those with sensitive skin, infants, and children should always be protected. Around midday, solar radiation is most harmful; hence, exposure should be limited. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Williamstown, WV
- Average high temperature in December: 41.7°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in December: 30.4°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in December
Williamstown, WV
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.96"Hg).
Average wind speed in December
Williamstown, WV
- Average wind speed in December: 6.2mph
The windiest month (with the highest average wind speed) is February (6.8mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in December
Williamstown, WV
- Average humidity in December: 82%
The months with the highest relative humidity are January and February (83%).
The months with the lowest relative humidity are June, July and August (76%).
Average rainfall in December
Williamstown, WV
- Average rainfall in December: 2.24"
The wettest month (with the highest rainfall) is May (3.19").
The driest month (with the least rainfall) is September (1.46").
Average rainfall days in December
Williamstown, WV
- Average rainfall days in December: 11.3 days
The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is November (8.4 days).
Average snowfall in December
Williamstown, WV
- Average snowfall in December: 1.46"
The month with the highest snowfall is February (2.8").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Williamstown, WV
- Average snowfall days in December: 5.4 days
The month with the highest number of snowfall days is January (9.5 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
Williamstown, WV
- Average daylight in December: 9h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 3h and 48min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in December
Williamstown, WV
- Average sunshine days in December: 15.8 days
The month with the most sunshine days is November (19.9 days).
The month with the least sunshine days is May (9.8 days).
Average UV index in December
Williamstown, WV
- Average UV index in December: 2
The months with the highest UV index are 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
Williamstown, WV
- Average cloud cover in December: 61
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in December
Williamstown, WV
- Average visibility in December: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).
