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
The coldest period tends to be December, when average temperatures fluctuate between a high of 42.6°F (5.9°C) and a low of 33.1°F (0.6°C).Humidity
In Grand Mound, the average relative humidity in December is 89%.Rainfall
In Grand Mound, in December, it is raining for 17.9 days, with typically 3.74" (95mm) of accumulated precipitation. Throughout the year, in Grand Mound, there are 168 rainfall days, and 23.94" (608mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through March, November and December. In Grand Mound, during December, snow falls for 1.2 days and regularly aggregates up to 0.31" (8mm) of snow. In Grand Mound, during the entire year, snow falls for 7.9 days and aggregates up to 4.02" (102mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 36min of daylight.On the first day of December, sunrise is at 7:37 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:56 am and sunset at 4:33 pm PST.
Sunshine
December has the least sunshine of the year, with an average of 3.5h of sunshine.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 value of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: An average maximum UV index of 2 in December leads to these recommendations:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Remember to consider! The UV radiation from the Sun can be intensified nearly twice by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What part of the year is the coldest?
How cold is December?
What is the average humidity in December?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When are sunrise and sunset in December?
What is the month with the least sunshine?
How long on average sun shines in December?
What are the months with the lowest UV index?
How high is the UV index in December?
Average temperature in December
Grand Mound, WA
- Average high temperature in December: 42.6°F
The warmest month (with the highest average high temperature) is August (77.4°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in December: 33.1°F
The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (33.1°F).
Average pressure in December
Grand Mound, WA
- Average pressure in December: 30.08"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.02"Hg).
Average wind speed in December
Grand Mound, WA
- Average wind speed in December: 4.2mph
The windiest months (with the highest average wind speed) are January, March and November (4.5mph).
The calmest month (with the lowest average wind speed) is September (3.6mph).
Average humidity in December
Grand Mound, WA
- Average humidity in December: 89%
The month with the highest relative humidity is November (90%).
The month with the lowest relative humidity is July (73%).
Average rainfall in December
Grand Mound, WA
- Average rainfall in December: 3.74"
The wettest month (with the highest rainfall) is January (3.86").
The driest month (with the least rainfall) is July (0.35").
Average rainfall days in December
Grand Mound, WA
- Average rainfall days in December: 17.9 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (5.6 days).
Average snowfall in December
Grand Mound, WA
- Average snowfall in December: 0.31"
The month with the highest snowfall is February (1.54").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Grand Mound, WA
- Average snowfall days in December: 1.2 days
The month with the highest number of snowfall days is February (2.7 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Grand Mound, WA
- Average daylight in December: 8h and 4min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in December: 3h and 3min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is December (Average sunshine: 3h and 30min).
Average sunshine days in December
Grand Mound, WA
- Average sunshine days in December: 10.8 days
The month with the most sunshine days is August (20.9 days).
The months with the least sunshine days are February and March (9.3 days).
Average UV index in December
Grand Mound, WA
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Grand Mound, WA
- Average cloud cover in December: 65
The month with the most cloud cover is January (Cloud cover 66).
The months with the least cloud cover are July and August (Cloud cover 38).
Average visibility in December
Grand Mound, WA
- Average visibility in December: 4mi
The month with the highest visibility is July (5mi).
The months with the lowest visibility are January, February, March, April, May, June, August, September, October, November and December (4mi).
Grand Mound, Washington, USA
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