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 sea temperature 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
Transition into December subtly marks a drop in the average high-temperature, moderately moving from a fresh 51.3°F (10.7°C) in November to a wintry 42.3°F (5.7°C). In Mystic, December nights experience a modest descent in temperature from daily peaks, cooling down to an average of 33.4°F (0.8°C).Humidity
In Mystic, the average relative humidity in December is 75%.Rainfall
December is the month with the most rainfall. Rain falls for 13.4 days and accumulates 3.86" (98mm) of precipitation.Snowfall
Months with snowfall in Mystic are January through April, October through December. In Mystic, during December, snow falls for 4.5 days and regularly aggregates up to 1.18" (30mm) of snow. In Mystic, during the entire year, snow falls for 24.7 days and aggregates up to 7.87" (200mm) of snow.Ocean temperature
In Mystic, the average seawater temperature in December is 48.6°F (9.2°C).Note: With the appropriate swimsuit, one can swim in 48.6°F (9.2°C) even if temperatures dip below 50°F (10°C); otherwise, be ready for cold shock and breath issues. A fleeting swim around 55.4°F (13°C) is distressing.
Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of December in Mystic, sunrise is at 6:55 am and sunset at 4:19 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 4:28 pm EST.
Sunshine
February and December, with an average of 4.9h of sunshine, are months with the least sunshine in Mystic.UV index
January through March and December, with an average maximum UV index of 2, are months with the lowest UV index in Mystic. A UV Index reading of 2, and below, represents a low health risk from exposure to the Sun's UV rays for the average person.Note: During December, 2 as the daily maximum UV index converts into the following advice:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Remember this! The UV radiation of the Sun can be nearly doubled by the reflective properties of snow.
Frequently asked questions
Is December cold in Mystic?
What is the average humidity in December in Mystic?
What is the wettest month in Mystic?
How much does it rain in Mystic in December?
How many days does it snow in December in Mystic?
How cold is the water in December in Mystic?
What is the month with the shortest days in Mystic?
What is the average length of the day in December in Mystic?
What time are sunrise and sunset in December in Mystic?
What are the months with the least sunshine in Mystic?
How long on average sun shines in December in Mystic?
What is the month with the lowest UV index in Mystic?
What is the UV index intensity in December in Mystic?
Average temperature in December
Mystic, CT
- Average high temperature in December: 42.3°F
The warmest month (with the highest average high temperature) is July (77.9°F).
The month with the lowest average high temperature is January (36.5°F).
- Average low temperature in December: 33.4°F
The month with the highest average low temperature is July (66.9°F).
The coldest month (with the lowest average low temperature) is January (26.6°F).
Average pressure in December
Mystic, CT
- Average pressure in December: 30.04"Hg
The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Mystic, CT
- Average wind speed in December: 11.9mph
The windiest month (with the highest average wind speed) is January (12.4mph).
The calmest month (with the lowest average wind speed) is August (8.1mph).
Average humidity in December
Mystic, CT
- Average humidity in December: 75%
The month with the highest relative humidity is June (81%).
The months with the lowest relative humidity are January, March, April and November (74%).
Average rainfall in December
Mystic, CT
- Average rainfall in December: 3.86"
The wettest month (with the highest rainfall) is December (3.86").
The driest month (with the least rainfall) is September (1.73").
Average rainfall days in December
Mystic, CT
- Average rainfall days in December: 13.4 days
The month with the highest number of rainy days is July (17.1 days).
The month with the least rainy days is February (10.1 days).
Average snowfall in December
Mystic, CT
- Average snowfall in December: 1.18"
The month with the highest snowfall is March (2.44").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Mystic, CT
- Average snowfall days in December: 4.5 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 and September (0 days).
Average sea temperature in December
Mystic, CT
- Average sea temperature in December: 48.6°F
The best month for swimming (with the highest average sea temperature) is August (70.3°F).
The coldest month (with the lowest average sea temperature) is February (37.9°F).
Average daylight in December /
Average sunshine in December
Mystic, CT
- Average daylight in December: 9h and 1min
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 12min).
- Average sunshine in December: 4h and 5min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are February and December (Average sunshine: 4h and 54min).
Average sunshine days in December
Mystic, CT
- Average sunshine days in December: 14.2 days
The month with the most sunshine days is November (16.5 days).
The months with the least sunshine days are June and July (11.7 days).
Average UV index in December
Mystic, CT
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March and December (UV index 2).
Average cloud cover in December
Mystic, CT
- Average cloud cover in December: 47
The months with the most cloud cover are February, March and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in December
Mystic, CT
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Mystic, Connecticut, USA
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