December weather forecastRockville Centre, NY
December
Weather in December
December, the first month of the winter in Rockville Centre, is still a chilly month, with an average temperature fluctuating between 43.7°F (6.5°C) and 36.7°F (2.6°C).Temperature
During the shift to December, Rockville Centre records a mild decrease in average high-temperature, moving from a fresh 51.6°F (10.9°C) in November to a frosty 43.7°F (6.5°C). In December, Rockville Centre's nighttime temperatures demonstrate a slight decrease, stabilizing at an average of 36.7°F (2.6°C).Humidity
The average relative humidity in December in Rockville Centre is 74%.Rainfall
In Rockville Centre, in December, during 11.5 rainfall days, 3.74" (95mm) of precipitation is typically accumulated. In Rockville Centre, during the entire year, the rain falls for 159.2 days and collects up to 37.17" (944mm) of precipitation.Snowfall
Months with snowfall are January through April, October through December. In Rockville Centre, in December, during 2.1 snowfall days, 0.98" (25mm) of snow is typically accumulated. Throughout the year, in Rockville Centre, there are 15.3 snowfall days, and 5.04" (128mm) of snow is accumulated.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December in Rockville Centre, 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 Rockville Centre, 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. A UV Index estimate of 2, and below, represents a minimal health hazard from unsafe exposure to UV radiation for the ordinary person.Note: A maximum high daily UV index of 2 during December translates into the following directions:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Take careful note! The UV radiation of the Sun can be nearly doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rockville Centre, NY
- Average high temperature in December: 43.7°F
The warmest month (with the highest average high temperature) is July (79°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in December: 36.7°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 (29.7°F).
Average pressure in December
Rockville Centre, 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
Rockville Centre, NY
- Average wind speed in December: 13.1mph
The windiest month (with the highest average wind speed) is January (13.6mph).
The calmest month (with the lowest average wind speed) is July (8.9mph).
Average humidity in December
Rockville Centre, 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
Rockville Centre, NY
- Average rainfall in December: 3.74"
The wettest month (with the highest rainfall) is July (4.17").
The driest month (with the least rainfall) is January (2.17").
Average rainfall days in December
Rockville Centre, NY
- Average rainfall days in December: 11.5 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is January (7.8 days).
Average snowfall in December
Rockville Centre, NY
- Average snowfall in December: 0.98"
The month with the highest snowfall is March (1.5").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Rockville Centre, NY
- Average snowfall days in December: 2.1 days
The months with the highest number of snowfall days are January and February (4.5 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Rockville Centre, 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
Rockville Centre, NY
- Average sunshine days in December: 16.6 days
The month with the most sunshine days is November (19.1 days).
The month with the least sunshine days is July (10.7 days).
Average UV index in December
Rockville Centre, 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
Rockville Centre, 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
Rockville Centre, 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).





