December weather forecastLynn, MA
December
Weather in December
Finally, December greets Lynn with a distinct winter chill, recording an average temperature drop to 30.2°F (-1°C). This month sees an upward spike in snowfall, reaching 3.43" (87mm) indicating that Christmas is round the corner. The sea temperature falls further, discouraging all but the bravest from taking a dip. Limited sunlight and increased rainfall make this month a perfect time for warm foods and indoor activities, wrapping up the year on a cosy note.Temperature
The average high-temperature drops in December, from November's frosty 49.5°F (9.7°C) to a cold 39.9°F (4.4°C). Nighttime temperatures consistently average a freezing cold 30.2°F (-1°C) during December.Humidity
In December, the average relative humidity is 76%.Rainfall
The month with the most rainfall is December, when the rain falls for 10.3 days and typically aggregates up to 2.99" (76mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In Lynn, in December, snow falls for 5.3 days, with typically accumulated 3.43" (87mm) of snow. Throughout the year, there are 29.9 snowfall days, and 15.59" (396mm) of snow is accumulated.Ocean temperature
In Lynn, the average seawater temperature in December is 46.2°F (7.9°C).Note: Swimming at temperatures less than 50°F (10°C) in 46.2°F (7.9°C) is feasible with the right swimsuit; if not, expect cold shock and breathlessness. A quick swim at 55.4°F (13°C) without adequate warmth can be discomforting.
Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year.On the first day of December in Lynn, sunrise is at 6:54 am and sunset at 4:11 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 4:21 pm EST.
Sunshine
February and December, with an average of 4.6h of sunshine, are months with the least sunshine.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: In December, the average maximum UV index of 2 translates into the following recommendations:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Caution! The reflection of snow 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
Average temperature in December
Lynn, MA
- Average high temperature in December: 39.9°F
The warmest month (with the highest average high temperature) is July (80.4°F).
The month with the lowest average high temperature is January (34.2°F).
- Average low temperature in December: 30.2°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure in December
Lynn, MA
- Average pressure in December: 30.03"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Lynn, MA
- Average wind speed in December: 10.3mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in December
Lynn, MA
- Average humidity in December: 76%
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is April (70%).
Average rainfall in December
Lynn, MA
- Average rainfall in December: 2.99"
The wettest month (with the highest rainfall) is December (2.99").
The driest month (with the least rainfall) is September (1.42").
Average rainfall days in December
Lynn, MA
- Average rainfall days in December: 10.3 days
The month with the highest number of rainy days is May (15.4 days).
The month with the least rainy days is January (7.1 days).
Average snowfall in December
Lynn, MA
- Average snowfall in December: 3.43"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Lynn, MA
- Average snowfall days in December: 5.3 days
The months with the highest number of snowfall days are January and February (7.7 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average sea temperature in December
Lynn, MA
- Average sea temperature in December: 46.3°F
The best month for swimming (with the highest average sea temperature) is August (67.6°F).
The coldest month (with the lowest average sea temperature) is March (38.8°F).
Average daylight in December /
Average sunshine in December
Lynn, MA
- Average daylight in December: 9h and 6min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 36min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The months with the least sunshine are February and December (Average sunshine: 4h and 36min).
Average sunshine days in December
Lynn, MA
- Average sunshine days in December: 16.1 days
The month with the most sunshine days is January (17.8 days).
The month with the least sunshine days is April (13.2 days).
Average UV index in December
Lynn, MA
- 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, November and December (UV index 2).
Average cloud cover in December
Lynn, MA
- Average cloud cover in December: 49
The month with the most cloud cover is March (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in December
Lynn, MA
- 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).
