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
The arrival of December corresponds with a shift in temperature, down from a chilly 49.8°F (9.9°C) in November to an icy 40.1°F (4.5°C). Allentown observes an average nighttime low-temperature of 28.9°F (-1.7°C) during the month of December.Humidity
In Allentown, the average relative humidity in December is 81%.Rainfall
In December, the rain falls for 9.2 days. Throughout December, 2.32" (59mm) of precipitation is accumulated. In Allentown, during the entire year, the rain falls for 145.1 days and collects up to 27.24" (692mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Allentown, during December, snow falls for 2.5 days and regularly aggregates up to 2.28" (58mm) of snow. In Allentown, during the entire year, snow falls for 20.4 days and aggregates up to 13.82" (351mm) 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 the month, sunrise is at 7:06 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:25 am and sunset at 4:45 pm EST.
Sunshine
The average sunshine in December is 4.7h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Allentown. A UV Index reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for average individuals.Note: The maximum UV index of 2 during December leads to these instructions:
Most individuals can handle sun exposure for up to an hour without burning, but children must always be shielded from sun exposure. The solar radiation around mid-day is intense; avoid the Sun and stay safe. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Notice! The UV radiation of the Sun can be intensified nearly twofold due to the reflective quality of snow.
Frequently asked questions
How cold is it in Allentown in December?
What is the average humidity in December in Allentown?
How many days does it rain in December in Allentown?
How many days does it snow in December in Allentown?
What is the month with the shortest days in Allentown?
What is the average length of the day in December in Allentown?
What time are sunrise and sunset in December in Allentown?
How many hours of sunshine does Allentown have in December?
When is the lowest UV index in Allentown?
How high is the UV index in December in Allentown?
Average temperature in December
Allentown, PA
- Average high temperature in December: 40.1°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (34°F).
- Average low temperature in December: 28.9°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in December
Allentown, PA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Allentown, PA
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Allentown, 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
Allentown, PA
- Average rainfall in December: 2.32"
The wettest month (with the highest rainfall) is July (3.03").
The driest month (with the least rainfall) is September (1.61").
Average rainfall days in December
Allentown, PA
- Average rainfall days in December: 9.2 days
The month with the highest number of rainy days is May (16.9 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in December
Allentown, PA
- Average snowfall in December: 2.28"
The month with the highest snowfall is March (4.37").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Allentown, PA
- Average snowfall days in December: 2.5 days
The month with the highest number of snowfall days is February (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Allentown, 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 18min).
- 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 24min).
Average sunshine days in December
Allentown, PA
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is January (20.5 days).
The month with the least sunshine days is May (11.8 days).
Average UV index in December
Allentown, PA
- Average UV index in December: 2
The months with the highest UV index are June and July (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
Allentown, PA
- Average cloud cover in December: 51
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 34).
Average visibility in December
Allentown, PA
- Average visibility in December: 5mi
The months with the highest visibility are April, July and November (6mi).
The months with the lowest visibility are January, February, March, May, June, August, September, October and December (5mi).
Allentown, Pennsylvania, USA
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