Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December's onset corresponds with a subtle shift in the average high-temperature, slightly moving from a cool 52.5°F (11.4°C) in November to a chilly 44.4°F (6.9°C). Riverhead's average nighttime temperature in December modestly descends to an icy 37°F (2.8°C).Humidity
In December, the average relative humidity is 74%.Rainfall
December is the month with the most rainfall. Rain falls for 13.1 days and accumulates 3.27" (83mm) of precipitation.Snowfall
Months with snowfall are January through March, May, November and December. In Riverhead, New York, in December, during 2.9 snowfall days, 0.59" (15mm) of snow is typically accumulated. Throughout the year, there are 18.6 snowfall days, and 4.45" (113mm) 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, sunrise is at 6:56 am and sunset at 4:23 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 4:32 pm EST.
Sunshine
In Riverhead, the average sunshine in December is 4.8h.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 reading of 2, and below, represents a minimal health hazard from exposure to the Sun's UV rays for average individuals.Note: The average daily UV index of 2 in December transforms into the following instructions:
People with sensitive skin, children, and babies should always be protected from prolonged sun exposure. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold does it get in December?
What is the average humidity in December?
What is the rainiest month?
How many days does it rain in December in Riverhead?
How many days does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Riverhead have in December?
When is the sunrise / sunset in December?
How long on average sun shines in December?
What is the month with the lowest UV index?
How high is the UV index in December?
Average temperature in December
Riverhead, NY
- Average high temperature in December: 44.4°F
The warmest month (with the highest average high temperature) is August (77.5°F).
The month with the lowest average high temperature is January (38.7°F).
- Average low temperature in December: 37°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 (30.6°F).
Average pressure in December
Riverhead, 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
Riverhead, NY
- Average wind speed in December: 14.2mph
The windiest month (with the highest average wind speed) is January (14.5mph).
The calmest month (with the lowest average wind speed) is July (9.5mph).
Average humidity in December
Riverhead, NY
- Average humidity in December: 74%
The month with the highest relative humidity is May (80%).
The month with the lowest relative humidity is November (71%).
Average rainfall in December
Riverhead, NY
- Average rainfall in December: 3.27"
The wettest month (with the highest rainfall) is December (3.27").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Riverhead, NY
- Average rainfall days in December: 13.1 days
The month with the highest number of rainy days is July (15.6 days).
The month with the least rainy days is February (9 days).
Average snowfall in December
Riverhead, NY
- Average snowfall in December: 0.59"
The month with the highest snowfall is March (1.54").
The months with the least snowfall are April, June, July, August, September and October (0").
Average snowfall days in December
Riverhead, NY
- Average snowfall days in December: 2.9 days
The month with the highest number of snowfall days is January (5.5 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Riverhead, NY
- Average daylight in December: 9h and 2min
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 5min
The months with the most sunshine are July and August (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
Riverhead, NY
- Average sunshine days in December: 13.5 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is February (13.2 days).
Average UV index in December
Riverhead, 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
Riverhead, NY
- Average cloud cover in December: 49
The month with the most cloud cover is December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Riverhead, 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).
Riverhead, New York, USA
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