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
During Hackettstown's transition into December, the average high-temperature lessens, moving from a frosty 49.1°F (9.5°C) in November to an icy 40.1°F (4.5°C). In December, in Hackettstown, the average low-temperature is a subzero cold 28.4°F (-2°C).Humidity
The months with the highest humidity are February, October and December, with an average relative humidity of 81%.Rainfall
In Hackettstown, in December, it is raining for 7.1 days, with typically 0.87" (22mm) of accumulated precipitation. In Hackettstown, during the entire year, the rain falls for 106.9 days and collects up to 9.84" (250mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In December, in Hackettstown, it is snowing for 3.2 days. Throughout December, 0.71" (18mm) of snow is accumulated. In Hackettstown, New Jersey, during the entire year, snow falls for 21.7 days and aggregates up to 3.94" (100mm) 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 7:05 am and sunset at 4:32 pm. On the last day of December, sunrise is at 7:23 am and sunset at 4:41 pm EST.
Sunshine
The average sunshine in December in Hackettstown is 4.7h.UV index
With an average maximum UV index of 1, December is the month with the lowest UV index. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation for average individuals.Note: The UV index of 1 during December translates into the following guidance:
Though extended exposure to the sun typically does not concern most people, it is crucial to always shield children, infants, and those with sensitive skin. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Frequently asked questions
Is December cold in Hackettstown?
What are the most humid months in Hackettstown?
What is the average humidity in December in Hackettstown?
How much does it rain in Hackettstown in December?
How many days does it snow in December in Hackettstown?
What is the month with the shortest days in Hackettstown?
What is the average length of the day in December in Hackettstown?
When are sunrise and sunset in December in Hackettstown?
How many hours of sunshine does Hackettstown have in December?
When is the lowest UV index in Hackettstown?
How high is the UV index in December in Hackettstown?
Average temperature in December
Hackettstown, NJ
- Average high temperature in December: 40.1°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 (33.8°F).
- Average low temperature in December: 28.4°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (21°F).
Average pressure in December
Hackettstown, NJ
- Average pressure in December: 30.08"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Hackettstown, NJ
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in December
Hackettstown, NJ
- Average humidity in December: 81%
The months with the highest relative humidity are February, October and December (81%).
The month with the lowest relative humidity is April (76%).
Average rainfall in December
Hackettstown, NJ
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is July (1.18").
The driest month (with the least rainfall) is September (0.35").
Average rainfall days in December
Hackettstown, NJ
- Average rainfall days in December: 7.1 days
The month with the highest number of rainy days is May (12.2 days).
The month with the least rainy days is January (5.9 days).
Average snowfall in December
Hackettstown, NJ
- Average snowfall in December: 0.71"
The month with the highest snowfall is February (0.98").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Hackettstown, NJ
- Average snowfall days in December: 3.2 days
The month with the highest number of snowfall days is February (6.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Hackettstown, NJ
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 15h and 6min).
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 18min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in December
Hackettstown, NJ
- Average sunshine days in December: 21.3 days
The month with the most sunshine days is January (21.5 days).
The month with the least sunshine days is May (15.4 days).
Average UV index in December
Hackettstown, NJ
- 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
Hackettstown, NJ
- 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 35).
Average visibility in December
Hackettstown, NJ
- Average visibility in December: 6mi
The months with the highest visibility are January, March, April, November and December (6mi).
The months with the lowest visibility are February, May, June, July, August, September and October (5mi).
Hackettstown, New Jersey, USA
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