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
Transition into December subtly marks a drop in the average high-temperature, moderately moving from a fresh 51.4°F (10.8°C) in November to a chilly 43.3°F (6.3°C). In December, Smithtown temperatures settle at a low of 36°F (2.2°C) during the nights, reflecting a minor change from daytime highs.Humidity
In December, the average relative humidity in Smithtown is 74%.Rainfall
In Smithtown, in December, during 12 rainfall days, 3.78" (96mm) of precipitation is typically accumulated. Throughout the year, there are 155.9 rainfall days, and 35.94" (913mm) of precipitation is accumulated.Snowfall
January through March, November and December are months with snowfall. In December, in Smithtown, it is snowing for 2.5 days. Throughout December, 1.42" (36mm) of snow is accumulated. Throughout the year, there are 15.4 snowfall days, and 5.71" (145mm) 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 6:58 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:17 am and sunset at 4:35 pm EST.
Sunshine
In December, the average sunshine is 4.9h.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 estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for the average person.Note: In December, the maximum UV index of 2 translates into these guidelines:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Boost your sun resistance with garments that are densely woven yet spacious. Remember this! The UV radiation of the Sun can be nearly doubled by the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold does it get in Smithtown in December?
What is the average humidity in December?
How much does it rain in Smithtown in December?
How many days does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Smithtown have in December?
What time are sunrise and sunset in December?
How many hours of sunshine does Smithtown have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Smithtown, NY
- Average high temperature in December: 43.3°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (37.6°F).
- Average low temperature in December: 36°F
The month with the highest average low temperature is August (71.6°F).
The coldest month (with the lowest average low temperature) is January (28.9°F).
Average pressure in December
Smithtown, 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
Smithtown, NY
- Average wind speed in December: 12.4mph
The windiest month (with the highest average wind speed) is January (12.8mph).
The calmest month (with the lowest average wind speed) is July (8.3mph).
Average humidity in December
Smithtown, NY
- Average humidity in December: 74%
The month with the highest relative humidity is May (77%).
The month with the lowest relative humidity is November (71%).
Average rainfall in December
Smithtown, NY
- Average rainfall in December: 3.78"
The wettest month (with the highest rainfall) is July (3.94").
The driest month (with the least rainfall) is January (2.2").
Average rainfall days in December
Smithtown, NY
- Average rainfall days in December: 12 days
The month with the highest number of rainy days is July (17.4 days).
The month with the least rainy days is January (7.8 days).
Average snowfall in December
Smithtown, NY
- Average snowfall in December: 1.42"
The month with the highest snowfall is March (1.85").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Smithtown, NY
- Average snowfall days in December: 2.5 days
The month with the highest number of snowfall days is February (4.8 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
Smithtown, 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 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
Smithtown, NY
- Average sunshine days in December: 17 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in December
Smithtown, 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
Smithtown, 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 28).
Average visibility in December
Smithtown, 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).
Smithtown, New York, USA
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