December weather forecastCosmopolis, WA
December
Weather in December
December, the first month of the winter in Cosmopolis, is also a frosty month, with an average temperature fluctuating between 36.5°F (2.5°C) and 44.2°F (6.8°C).Temperature
December is the coldest month, exhibiting average temperatures of 44.2°F (6.8°C) at the peak and 36.5°F (2.5°C) at the base.Humidity
November and December, with an average relative humidity of 88%, are the most humid months.Rainfall
In Cosmopolis, in December, it is raining for 12.7 days, with typically 1.77" (45mm) of accumulated precipitation. In Cosmopolis, during the entire year, the rain falls for 113.5 days and collects up to 10.24" (260mm) of precipitation.Snowfall
April through December are months without snowfall.Daylight
The month with the shortest days is December, with an average of 8h and 36min of daylight.On the first day of the month, sunrise is at 7:40 am and sunset at 4:28 pm. On the last day of December, sunrise is at 8:00 am and sunset at 4:36 pm PST.
Sunshine
The average sunshine in December is 3.6h.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 reading of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the average person.Note: The UV index of 2 during December translates into the following guidance:
Protection from prolonged sun exposure is necessary for babies, children, and individuals with sensitive skin. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Cosmopolis, WA
- Average high temperature in December: 44.2°F
The warmest month (with the highest average high temperature) is August (71.4°F).
The month with the lowest average high temperature is December (44.2°F).
- Average low temperature in December: 36.5°F
The month with the highest average low temperature is August (51.1°F).
The coldest month (with the lowest average low temperature) is December (36.5°F).
Average pressure in December
Cosmopolis, WA
- Average pressure in December: 30.05"Hg
The month with the highest atmospheric pressure is July (30.08"Hg).
The month with the lowest atmospheric pressure is March (30.01"Hg).
Average wind speed in December
Cosmopolis, WA
- Average wind speed in December: 6.5mph
The windiest month (with the highest average wind speed) is January (7mph).
The calmest month (with the lowest average wind speed) is September (4.7mph).
Average humidity in December
Cosmopolis, WA
- Average humidity in December: 88%
The months with the highest relative humidity are November and December (88%).
The month with the lowest relative humidity is July (78%).
Average rainfall in December
Cosmopolis, WA
- Average rainfall in December: 1.77"
The wettest month (with the highest rainfall) is January (1.93").
The driest months (with the least rainfall) are July and August (0.12").
Average rainfall days in December
Cosmopolis, WA
- Average rainfall days in December: 12.7 days
The month with the highest number of rainy days is March (13.6 days).
The month with the least rainy days is August (3.2 days).
Average snowfall in December
Cosmopolis, WA
- Average snowfall in December: 0"
The months with the highest snowfall are January and February (0.28").
The months with the least snowfall are April, May, June, July, August, September, October, November and December (0").
Average snowfall days in December
Cosmopolis, WA
- Average snowfall days in December: 0.1 days
The month with the highest number of snowfall days is February (1.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Cosmopolis, WA
- Average daylight in December: 8h and 36min
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 36min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in December
Cosmopolis, WA
- Average sunshine days in December: 16.8 days
The month with the most sunshine days is August (25.4 days).
The months with the least sunshine days are February and March (14.1 days).
Average UV index in December
Cosmopolis, WA
- Average UV index in December: 2
The month with the highest UV index is 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
Cosmopolis, WA
- Average cloud cover in December: 62
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is July (Cloud cover 37).
Average visibility in December
Cosmopolis, WA
- Average visibility in December: 4mi
The months with the highest visibility are February, March, April, May, June and November (5mi).
The months with the lowest visibility are January, July, August, September, October and December (4mi).
