December weather forecastWest Jonestown, PA
December
Weather in December
December, the first month of the winter in West Jonestown, is still a cold month, with temperature in the range of an average high of 39.9°F (4.4°C) and an average low of 28.8°F (-1.8°C).Temperature
The onset of December introduces a moderate change in West Jonestown's weather, with average high-temperatures falling from November's frosty 49.5°F (9.7°C) to a cold 39.9°F (4.4°C). In West Jonestown, December nights cool down to an average of 28.8°F (-1.8°C).Humidity
The average relative humidity in December is 80%.Rainfall
In West Jonestown, in December, during 11 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. Throughout the year, there are 166.3 rainfall days, and 34.53" (877mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In West Jonestown, in December, snow falls for 5.9 days, with typically accumulated 1.97" (50mm) of snow. In West Jonestown, during the entire year, snow falls for 32.4 days and aggregates up to 16.69" (424mm) of snow.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:10 am and sunset at 4:40 pm. On the last day of the month, sunrise is at 7:28 am and sunset at 4:49 pm EST.
Sunshine
In West Jonestown, the average sunshine in December is 4.4h.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 low health risk from exposure to the Sun's UV radiation for the average person.Note: A maximum UV index of 2 in December translates into the following recommendations:
Prolonged exposure to sunlight rarely troubles the majority, but constant protection is vital for babies, children, and fair-skinned people. Minimize direct exposure to the Sun during midday when its radiation is at its peak. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
West Jonestown, PA
- Average high temperature in December: 39.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in December: 28.8°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (21.2°F).
Average pressure in December
West Jonestown, PA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
West Jonestown, PA
- Average wind speed in December: 7.8mph
The windiest month (with the highest average wind speed) is March (8.7mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
West Jonestown, PA
- Average humidity in December: 80%
The months with the highest relative humidity are February, May, June and October (81%).
The month with the lowest relative humidity is April (76%).
Average rainfall in December
West Jonestown, PA
- Average rainfall in December: 2.68"
The wettest months (with the highest rainfall) are May and July (3.58").
The driest month (with the least rainfall) is September (2.32").
Average rainfall days in December
West Jonestown, PA
- Average rainfall days in December: 11 days
The month with the highest number of rainy days is May (18.6 days).
The month with the least rainy days is January (9.1 days).
Average snowfall in December
West Jonestown, PA
- Average snowfall in December: 1.97"
The month with the highest snowfall is January (5.08").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
West Jonestown, PA
- Average snowfall days in December: 5.9 days
The month with the highest number of snowfall days is January (10.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
West Jonestown, PA
- Average daylight in December: 9h and 18min
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 24min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 18min).
Average sunshine days in December
West Jonestown, PA
- Average sunshine days in December: 14.8 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is May (10.1 days).
Average UV index in December
West Jonestown, PA
- Average UV index in December: 2
The month with the highest UV index is June (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
West Jonestown, PA
- Average cloud cover in December: 53
The months with the most cloud cover are February and December (Cloud cover 53).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in December
West Jonestown, PA
- Average visibility in December: 5mi
The months with the highest visibility are March, April, June, July and November (6mi).
The months with the lowest visibility are January, February, May, August, September, October and December (5mi).
