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
With December's arrival, Lancaster's weather changes as the average high-temperature falls from a cool 51.3°F (10.7°C) in November to an icy 42.1°F (5.6°C). Throughout the nights in December, Lancaster experiences an average low-temperature of 30°F (-1.1°C).Humidity
In December, the average relative humidity is 79%.Rainfall
In Lancaster, in December, during 10.7 rainfall days, 2.09" (53mm) of precipitation is typically accumulated. In Lancaster, during the entire year, the rain falls for 153.4 days and collects up to 28.27" (718mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Lancaster, during December, snow falls for 3.5 days and regularly aggregates up to 1.22" (31mm) of snow. Throughout the year, there are 20.8 snowfall days, and 11.46" (291mm) of snow is accumulated.Daylight
With an average of 9h and 24min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:08 am and sunset at 4:40 pm. On the last day of the month, sunrise is at 7:27 am and sunset at 4:50 pm EST.
Sunshine
In Lancaster, Pennsylvania, the average sunshine in December is 4.7h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV rays for the ordinary person.Note: In December, the maximum UV index of 2 translates into these guidelines:
Children, babies, and those with sensitive skin should always be shielded from long periods of sun exposure. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in December?
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 in Lancaster?
When are sunrise and sunset in December in Lancaster?
How many hours of sunshine does Lancaster have in December?
When is the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Lancaster, PA
- Average high temperature in December: 42.1°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in December: 30°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (23.2°F).
Average pressure in December
Lancaster, 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
Lancaster, PA
- Average wind speed in December: 8.4mph
The windiest month (with the highest average wind speed) is March (9mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in December
Lancaster, PA
- Average humidity in December: 79%
The month with the highest relative humidity is May (81%).
The month with the lowest relative humidity is April (76%).
Average rainfall in December
Lancaster, PA
- Average rainfall in December: 2.09"
The wettest month (with the highest rainfall) is August (3.35").
The driest months (with the least rainfall) are February and September (1.89").
Average rainfall days in December
Lancaster, PA
- Average rainfall days in December: 10.7 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is February (8 days).
Average snowfall in December
Lancaster, PA
- Average snowfall in December: 1.22"
The month with the highest snowfall is March (3.66").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Lancaster, PA
- Average snowfall days in December: 3.5 days
The month with the highest number of snowfall days is January (6.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Lancaster, 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 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 30min).
Average sunshine days in December
Lancaster, PA
- Average sunshine days in December: 17.1 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is May (11.3 days).
Average UV index in December
Lancaster, 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
Lancaster, PA
- Average cloud cover in December: 49
The month with the most cloud cover is February (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in December
Lancaster, PA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, October, November and December (6mi).
The months with the lowest visibility are May, August and September (5mi).
Lancaster, Pennsylvania, USA
Weather forecast for your location
2. Allow the app to use your location