December weather forecastHewlett Harbor, NY
December
Weather in December
The first month of the winter, December, is still a chilly month in Hewlett Harbor, New York, with an average temperature ranging between min 36°F (2.2°C) and max 43.5°F (6.4°C).Temperature
A moderate decline in average high-temperatures is noted in December, moving from a cool 51.6°F (10.9°C) in November to a frosty 43.5°F (6.4°C). With a barely noticeable fluctuation in temperature, Hewlett Harbor reaches an average low of 36°F (2.2°C) during the December nights.Humidity
In December, the average relative humidity in Hewlett Harbor, New York, is 75%.Rainfall
In Hewlett Harbor, during December, the rain falls for 10.7 days and regularly aggregates up to 1.65" (42mm) of precipitation. In Hewlett Harbor, during the entire year, the rain falls for 135.3 days and collects up to 18.62" (473mm) of precipitation.Snowfall
Months with snowfall are January through March, October through December. In December, it is snowing for 2.8 days. Throughout December, 0.59" (15mm) of snow is accumulated. In Hewlett Harbor, New York, during the entire year, snow falls for 15.8 days and aggregates up to 2.95" (75mm) of snow.Ocean temperature
In December, the average ocean temperature is 48°F (8.9°C).Note: With an efficient thermal swimsuit, one can navigate 48°F (8.9°C) even if it's colder than 50°F (10°C); otherwise, rapid cold shock and breathlessness might set in. Barely wading at 55.4°F (13°C) feels chilly.
Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year in Hewlett Harbor.On the first day of December, sunrise is at 6:59 am and sunset at 4:28 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 4:37 pm EST.
Sunshine
In Hewlett Harbor, the average sunshine in December is 5h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Hewlett Harbor. A UV Index value of 2, and less, symbolizes a low health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A typical high UV index of 2 in December suggests the following recommendations:
People with sensitive skin, children, and babies should always be protected from prolonged sun exposure. Avoid the Sun's strongest UV rays by seeking shade and limiting exposure during midday. Tightly woven clothing, when worn loosely, shields effectively against the Sun. Be on the lookout! Nearly twofold UV radiation from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Hewlett Harbor, NY
- Average high temperature in December: 43.5°F
The warmest month (with the highest average high temperature) is July (80.6°F).
The month with the lowest average high temperature is January (37°F).
- Average low temperature in December: 36°F
The month with the highest average low temperature is August (71.1°F).
The coldest month (with the lowest average low temperature) is January (28.2°F).
Average pressure in December
Hewlett Harbor, NY
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Hewlett Harbor, NY
- 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 July (8mph).
Average humidity in December
Hewlett Harbor, NY
- Average humidity in December: 75%
The month with the highest relative humidity is May (77%).
The month with the lowest relative humidity is November (72%).
Average rainfall in December
Hewlett Harbor, NY
- Average rainfall in December: 1.65"
The wettest months (with the highest rainfall) are July and August (2.32").
The driest month (with the least rainfall) is January (0.91").
Average rainfall days in December
Hewlett Harbor, NY
- Average rainfall days in December: 10.7 days
The month with the highest number of rainy days is July (15.1 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in December
Hewlett Harbor, NY
- Average snowfall in December: 0.59"
The month with the highest snowfall is March (1.02").
The months with the least snowfall are April, May, June, July, August and September (0").
Average snowfall days in December
Hewlett Harbor, NY
- Average snowfall days in December: 2.8 days
The month with the highest number of snowfall days is January (4.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average sea temperature in December
Hewlett Harbor, NY
- Average sea temperature in December: 48.1°F
The best month for swimming (with the highest average sea temperature) is August (74.1°F).
The coldest month (with the lowest average sea temperature) is February (39.9°F).
Average daylight in December /
Average sunshine in December
Hewlett Harbor, 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: 5h and 0min
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
Hewlett Harbor, NY
- Average sunshine days in December: 16.9 days
The month with the most sunshine days is January (19.8 days).
The month with the least sunshine days is July (13.6 days).
Average UV index in December
Hewlett Harbor, 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, November and December (UV index 2).
Average cloud cover in December
Hewlett Harbor, NY
- Average cloud cover in December: 47
The months with the most cloud cover are February and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Hewlett Harbor, 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).





