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, having an average high-temperature of 36.1°F (2.3°C) and an average low-temperature of 25.3°F (-3.7°C), is the coldest month.Humidity
In Sunnyside, Washington, the average relative humidity in December is 81%.Rainfall
In Sunnyside, during December, the rain falls for 10.4 days and regularly aggregates up to 1.06" (27mm) of precipitation. Throughout the year, there are 104.5 rainfall days, and 8.23" (209mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through March, September, November and December. The month with the most snowfall is December, when snow falls for 5 days and typically aggregates up to 2.24" (57mm) of snow.Daylight
December has the shortest days of the year, with an average of 8h and 42min of daylight.On the first day of the month, sunrise is at 7:23 am and sunset at 4:15 pm. On the last day of December, sunrise is at 7:43 am and sunset at 4:23 pm PST.
Sunshine
The average sunshine in December is 5.1h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for average individuals.Note: In December, a daily maximum UV index of 2 leads to the following instructions:
Most individuals face no major issues with lengthy exposure to the sun, but children, infants, and individuals with fair skin always require protection. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the coldest month?
How cold is it in December?
What is the average humidity in December?
How many days does it rain in December?
What is the snowiest month?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
What time are sunrise and sunset in December?
How many hours of sunshine does Sunnyside have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Sunnyside, WA
- Average high temperature in December: 36.1°F
The warmest month (with the highest average high temperature) is July (87.1°F).
The month with the lowest average high temperature is December (36.1°F).
- Average low temperature in December: 25.3°F
The month with the highest average low temperature is August (61.5°F).
The coldest month (with the lowest average low temperature) is December (25.3°F).
Average pressure in December
Sunnyside, WA
- Average pressure in December: 30.15"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is August (29.92"Hg).
Average wind speed in December
Sunnyside, WA
- Average wind speed in December: 5mph
The windiest month (with the highest average wind speed) is April (8.3mph).
The calmest month (with the lowest average wind speed) is December (5mph).
Average humidity in December
Sunnyside, WA
- Average humidity in December: 81%
The month with the highest relative humidity is January (83%).
The months with the lowest relative humidity are July and August (38%).
Average rainfall in December
Sunnyside, WA
- Average rainfall in December: 1.06"
The wettest month (with the highest rainfall) is May (1.1").
The driest month (with the least rainfall) is July (0.24").
Average rainfall days in December
Sunnyside, WA
- Average rainfall days in December: 10.4 days
The month with the highest number of rainy days is March (13.3 days).
The month with the least rainy days is July (4.1 days).
Average snowfall in December
Sunnyside, WA
- Average snowfall in December: 2.24"
The month with the highest snowfall is December (2.24").
The months with the least snowfall are April, May, June, July, August and October (0").
Average snowfall days in December
Sunnyside, WA
- Average snowfall days in December: 5 days
The month with the highest number of snowfall days is December (5 days).
The months with the least snowfall days are April, May, June, July, August and October (0 days).
Average daylight in December /
Average sunshine in December
Sunnyside, WA
- Average daylight in December: 8h and 4min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in December: 5h and 1min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 54min).
Average sunshine days in December
Sunnyside, WA
- Average sunshine days in December: 16.2 days
The month with the most sunshine days is July (26.2 days).
The month with the least sunshine days is March (15.4 days).
Average UV index in December
Sunnyside, WA
- 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, November and December (UV index 2).
Average cloud cover in December
Sunnyside, WA
- Average cloud cover in December: 47
The month with the most cloud cover is January (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 10).
Average visibility in December
Sunnyside, WA
- Average visibility in December: 5mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
Sunnyside, Washington, USA
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