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
December brings a decrease in the average high-temperature, falling from November's cool 50.7°F (10.4°C) to a wintry 41.5°F (5.3°C). Throughout December, the temperature falls to an average low of 29.8°F (-1.2°C).Humidity
In December, the average relative humidity is 79%.Rainfall
In Gettysburg, in December, during 7.5 rainfall days, 0.87" (22mm) of precipitation is typically accumulated. Throughout the year, there are 125 rainfall days, and 12.13" (308mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. In Gettysburg, in December, snow falls for 3.4 days, with typically accumulated 0.83" (21mm) of snow. Throughout the year, there are 20.9 snowfall days, and 4.8" (122mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:11 am and sunset at 4:44 pm. On the last day of December, sunrise is at 7:30 am and sunset at 4:54 pm EST.
Sunshine
The average sunshine in December is 4.9h.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 reading of 2, and below, represents a minimal health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum high UV index of 2 in December translates into the following recommendations:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold does it get in December?
What is the average humidity in December?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When are sunrise and sunset in December?
How long on average sun shines in December?
What are the months with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Gettysburg, PA
- Average high temperature in December: 41.5°F
The warmest month (with the highest average high temperature) is July (84°F).
The month with the lowest average high temperature is January (35.6°F).
- Average low temperature in December: 29.8°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (22.6°F).
Average pressure in December
Gettysburg, 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
Gettysburg, PA
- Average wind speed in December: 7.6mph
The windiest months (with the highest average wind speed) are January, February and March (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Gettysburg, PA
- Average humidity in December: 79%
The month with the highest relative humidity is May (80%).
The months with the lowest relative humidity are April and July (75%).
Average rainfall in December
Gettysburg, PA
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is July (1.46").
The driest months (with the least rainfall) are January and February (0.71").
Average rainfall days in December
Gettysburg, PA
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is May (14.8 days).
The month with the least rainy days is January (5 days).
Average snowfall in December
Gettysburg, PA
- Average snowfall in December: 0.83"
The month with the highest snowfall is March (1.3").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Gettysburg, PA
- Average snowfall days in December: 3.4 days
The month with the highest number of snowfall days is February (6.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Gettysburg, PA
- Average daylight in December: 9h and 2min
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: 4h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Gettysburg, PA
- Average sunshine days in December: 20.6 days
The month with the most sunshine days is November (21.6 days).
The month with the least sunshine days is August (13.6 days).
Average UV index in December
Gettysburg, 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
Gettysburg, PA
- Average cloud cover in December: 47
The month with the most cloud cover is February (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in December
Gettysburg, PA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).
Gettysburg, Pennsylvania, USA
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