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
A change in temperatures is noted as November gives way to December, with average highs reducing from a frosty 49.5°F (9.7°C) to a wintry 39.9°F (4.4°C). During the nights in December, Gratztown observes an average low-temperature of 28.4°F (-2°C).Humidity
In Gratztown, the average relative humidity in December is 84%.Rainfall
In Gratztown, in December, during 12.7 rainfall days, 1.97" (50mm) of precipitation is typically accumulated. In Gratztown, Pennsylvania, during the entire year, the rain falls for 174.1 days and collects up to 23.82" (605mm) of precipitation.Snowfall
Months with snowfall are January through April, October through December. In Gratztown, in December, during 11.5 snowfall days, 2.91" (74mm) of snow is typically accumulated. Throughout the year, there are 54.8 snowfall days, and 13.58" (345mm) 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 the month, sunrise is at 7:23 am and sunset at 4:53 pm. On the last day of December, sunrise is at 7:41 am and sunset at 5:03 pm EST.
Sunshine
In December, the average sunshine in Gratztown is 3.6h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In December, an average UV index of 1 transforms into the following instructions:
Unlike children, who always need sun protection, most individuals can remain in the sun for up to an hour without getting burnt. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. Keep in mind! Snow's reflective quality can nearly double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
How many days does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Gratztown have in December?
When are sunrise and sunset in December?
How many hours of sunshine does Gratztown have in December?
What is the month with the lowest UV index?
What is the UV index reading in December in Gratztown?
Average temperature in December
Gratztown, PA
- Average high temperature in December: 39.9°F
The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in December: 28.4°F
The month with the highest average low temperature is July (60.8°F).
The coldest month (with the lowest average low temperature) is January (20.7°F).
Average pressure in December
Gratztown, PA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in December
Gratztown, PA
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is January (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in December
Gratztown, PA
- Average humidity in December: 84%
The month with the highest relative humidity is February (85%).
The months with the lowest relative humidity are April, July and August (77%).
Average rainfall in December
Gratztown, PA
- Average rainfall in December: 1.97"
The wettest month (with the highest rainfall) is May (2.83").
The driest month (with the least rainfall) is November (1.42").
Average rainfall days in December
Gratztown, PA
- Average rainfall days in December: 12.7 days
The month with the highest number of rainy days is May (19.7 days).
The month with the least rainy days is February (10 days).
Average snowfall in December
Gratztown, PA
- Average snowfall in December: 2.91"
The month with the highest snowfall is January (3.66").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Gratztown, PA
- Average snowfall days in December: 11.5 days
The month with the highest number of snowfall days is January (16.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Gratztown, 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: 3h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 3h and 0min).
Average sunshine days in December
Gratztown, PA
- Average sunshine days in December: 9.5 days
The month with the most sunshine days is November (15.8 days).
The month with the least sunshine days is January (7.3 days).
Average UV index in December
Gratztown, PA
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Gratztown, PA
- Average cloud cover in December: 64
The month with the most cloud cover is January (Cloud cover 68).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in December
Gratztown, 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).
Gratztown, Pennsylvania, USA
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