December weather forecastShelter Island, NY
December
Weather in December
The first month of the winter, December, is also a frosty month in Shelter Island, New York, with an average temperature varying between 45°F (7.2°C) and 37.9°F (3.3°C).Temperature
With the arrival of December, Shelter Island notices a mild change in the average high-temperature, sliding from November's fresh 52.7°F (11.5°C) to a chilly 45°F (7.2°C). Shelter Island's average low temperature, barely cooler than the daytime high, steadies at an icy 37.9°F (3.3°C) during December.Humidity
The average relative humidity in December is 74%.Rainfall
December is the month with the most rainfall. Rain falls for 12.8 days and accumulates 3.82" (97mm) of precipitation.Snowfall
Months with snowfall are January through March, November and December. In December, in Shelter Island, it is snowing for 2.3 days. Throughout December, 0.91" (23mm) of snow is accumulated. In Shelter Island, during the entire year, snow falls for 13.9 days and aggregates up to 6.61" (168mm) 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 6:55 am and sunset at 4:21 pm. On the last day of December, in Shelter Island, sunrise is at 7:14 am and sunset at 4:31 pm EST.
Sunshine
December has the least sunshine of the year, with an average of 4.6h of sunshine.UV index
The months with the lowest UV index are January through March and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum high daily UV index of 2 during December translates into the following directions:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Shelter Island, NY
- Average high temperature in December: 45°F
The warmest month (with the highest average high temperature) is August (75.9°F).
The month with the lowest average high temperature is January (38.8°F).
- Average low temperature in December: 37.9°F
The month with the highest average low temperature is August (71.2°F).
The coldest month (with the lowest average low temperature) is January (31.3°F).
Average pressure in December
Shelter Island, NY
- Average pressure in December: 30.05"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
Shelter Island, NY
- Average wind speed in December: 15.7mph
The windiest month (with the highest average wind speed) is January (16mph).
The calmest month (with the lowest average wind speed) is July (10.4mph).
Average humidity in December
Shelter Island, NY
- Average humidity in December: 74%
The months with the highest relative humidity are May and June (81%).
The month with the lowest relative humidity is November (72%).
Average rainfall in December
Shelter Island, NY
- Average rainfall in December: 3.82"
The wettest month (with the highest rainfall) is December (3.82").
The driest month (with the least rainfall) is September (2.17").
Average rainfall days in December
Shelter Island, NY
- Average rainfall days in December: 12.8 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is January (9.1 days).
Average snowfall in December
Shelter Island, NY
- Average snowfall in December: 0.91"
The month with the highest snowfall is March (2.36").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Shelter Island, NY
- Average snowfall days in December: 2.3 days
The month with the highest number of snowfall days is January (4.2 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Shelter Island, NY
- Average daylight in December: 9h and 18min
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 36min
The months with the most sunshine are July and August (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 4h and 36min).
Average sunshine days in December
Shelter Island, NY
- Average sunshine days in December: 13.7 days
The month with the most sunshine days is November (16.8 days).
The month with the least sunshine days is February (12.8 days).
Average UV index in December
Shelter Island, NY
- 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
Shelter Island, NY
- Average cloud cover in December: 52
The month with the most cloud cover is December (Cloud cover 52).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Shelter Island, NY
- 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).





