December weather forecastCrystal Spring, PA
December
Weather in December
December, the first month of the winter in Crystal Spring, is still a cold month, with an average temperature fluctuating between 38.5°F (3.6°C) and 27.5°F (-2.5°C).Temperature
The onset of December brings a small change in high-temperatures, falling from a frosty 48.2°F (9°C) in November to an icy 38.5°F (3.6°C). Crystal Spring's average low-temperature for the month of December records at a subzero cold 27.5°F (-2.5°C).Humidity
In December, the average relative humidity is 81%.Rainfall
In Crystal Spring, during December, the rain falls for 7.3 days and regularly aggregates up to 1.14" (29mm) of precipitation. Throughout the year, in Crystal Spring, there are 126 rainfall days, and 15.47" (393mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, October through December. In Crystal Spring, during December, snow falls for 4.5 days and regularly aggregates up to 1.14" (29mm) of snow. In Crystal Spring, during the entire year, snow falls for 28.3 days and aggregates up to 9.57" (243mm) of snow.Daylight
With an average of 9h and 24min of daylight, December has the shortest days of the year in Crystal Spring.On the first day of the month, sunrise is at 7:16 am and sunset at 4:48 pm. On the last day of December, sunrise is at 7:34 am and sunset at 4:58 pm EST.
Sunshine
The average sunshine in December in Crystal Spring is 4.3h.UV index
The months with the lowest UV index in Crystal Spring are January through March, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for the ordinary person.Note: The maximum UV index of 2 during December translates into these guidelines:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Opt for tightly woven and loose clothing to enhance protection from the Sun. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Crystal Spring, PA
- Average high temperature in December: 38.5°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (32.7°F).
- Average low temperature in December: 27.5°F
The month with the highest average low temperature is July (60.1°F).
The coldest month (with the lowest average low temperature) is January (20.1°F).
Average pressure in December
Crystal Spring, 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
Crystal Spring, PA
- Average wind speed in December: 8mph
The windiest month (with the highest average wind speed) is January (8.6mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in December
Crystal Spring, 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
Crystal Spring, PA
- Average rainfall in December: 1.14"
The wettest month (with the highest rainfall) is May (1.81").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in December
Crystal Spring, PA
- Average rainfall days in December: 7.3 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is January (6 days).
Average snowfall in December
Crystal Spring, PA
- Average snowfall in December: 1.14"
The month with the highest snowfall is January (2.76").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Crystal Spring, PA
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is January (7.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Crystal Spring, PA
- Average daylight in December: 9h and 24min
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 18min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in December
Crystal Spring, PA
- Average sunshine days in December: 20.2 days
The month with the most sunshine days is December (20.2 days).
The month with the least sunshine days is May (12.8 days).
Average UV index in December
Crystal Spring, 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
Crystal Spring, PA
- Average cloud cover in December: 55
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is July (Cloud cover 35).
Average visibility in December
Crystal Spring, PA
- 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).





