December weather forecastSayville, NY
December
Weather in December
December, the first month of the winter in Sayville, is still a chilly month, with an average temperature fluctuating between 37.2°F (2.9°C) and 44.1°F (6.7°C).Temperature
December signifies a gentle decline in Sayville's average high-temperature, easing from a cool 52.3°F (11.3°C) in November to a chilly 44.1°F (6.7°C). In Sayville, the December nights are characterized by an average low-temperature of 37.2°F (2.9°C), a minor dip from daytime readings.Humidity
The average relative humidity in December is 74%.Rainfall
The month with the most rainfall in Sayville is December, when the rain falls for 12.3 days and typically aggregates up to 3.74" (95mm) of precipitation.Snowfall
January through March, May, October and December are months with snowfall in Sayville. December is the first month it typically snows in Sayville. Throughout December, in the average 2.4 snowfall days, it receives 1.22" (31mm) of snow. Throughout the year, in Sayville, there are 14.7 snowfall days, and 6.14" (156mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of December in Sayville, sunrise is at 6:57 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:16 am and sunset at 4:35 pm EST.
Sunshine
In Sayville, New York, the average sunshine in December is 4.9h.UV index
January through March and December, with an average maximum UV index of 2, are months with the lowest UV index in Sayville. A UV Index reading of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index, 2 in December, converts into the following recommendations:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Sayville, NY
- Average high temperature in December: 44.1°F
The warmest month (with the highest average high temperature) is August (78.1°F).
The month with the lowest average high temperature is January (37.9°F).
- Average low temperature in December: 37.2°F
The month with the highest average low temperature is August (71.8°F).
The coldest month (with the lowest average low temperature) is January (30.2°F).
Average pressure in December
Sayville, NY
- Average pressure in December: 30.06"Hg
The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Sayville, NY
- Average wind speed in December: 13.4mph
The windiest month (with the highest average wind speed) is January (13.8mph).
The calmest months (with the lowest average wind speed) are July and August (9mph).
Average humidity in December
Sayville, NY
- Average humidity in December: 74%
The months with the highest relative humidity are May and June (78%).
The month with the lowest relative humidity is November (71%).
Average rainfall in December
Sayville, NY
- Average rainfall in December: 3.74"
The wettest month (with the highest rainfall) is December (3.74").
The driest month (with the least rainfall) is January (2.17").
Average rainfall days in December
Sayville, NY
- Average rainfall days in December: 12.3 days
The month with the highest number of rainy days is July (17.7 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in December
Sayville, NY
- Average snowfall in December: 1.22"
The month with the highest snowfall is March (2.13").
The months with the least snowfall are April, June, July, August, September and November (0").
Average snowfall days in December
Sayville, NY
- Average snowfall days in December: 2.4 days
The month with the highest number of snowfall days is February (4.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Sayville, NY
- Average daylight in December: 9h and 18min
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 54min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in December
Sayville, NY
- Average sunshine days in December: 16.9 days
The month with the most sunshine days is November (18.8 days).
The month with the least sunshine days is July (11.3 days).
Average UV index in December
Sayville, 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
Sayville, NY
- Average cloud cover in December: 48
The month with the most cloud cover is December (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Sayville, 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).
