December weather forecastRosalia, WA
December
Weather in December
December, the first month of the winter in Rosalia, is also an icy month, with temperature in the range of an average high of 33.1°F (0.6°C) and an average low of 23.9°F (-4.5°C).Temperature
December, characterized by an average high temperature of 33.1°F (0.6°C) and a low temperature of 23.9°F (-4.5°C), is generally the coldest month.Humidity
The average relative humidity in December is 85%.Rainfall
In Rosalia, in December, during 6.5 rainfall days, 0.79" (20mm) of precipitation is typically accumulated. Throughout the year, there are 84.3 rainfall days, and 7.24" (184mm) of precipitation is accumulated.Snowfall
January through May, September, November and December are months with snowfall. In December, it is snowing for 9.3 days. Throughout December, 2.91" (74mm) of snow is accumulated. Throughout the year, there are 32.5 snowfall days, and 14.09" (358mm) of snow is accumulated.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 7:16 am and sunset at 4:01 pm. On the last day of December, sunrise is at 7:36 am and sunset at 4:09 pm PST.
Sunshine
December has the least sunshine of the year, with an average of 4.3h of sunshine.UV index
The months with the lowest UV index in Rosalia, Washington, are January, February, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for average individuals.Note: An average UV index of 2 in December transforms into this advice:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. Around midday, solar radiation is most harmful; hence, exposure should be limited. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Be on the lookout! Nearly twofold UV radiation from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rosalia, WA
- Average high temperature in December: 33.1°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is December (33.1°F).
- Average low temperature in December: 23.9°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is December (23.9°F).
Average pressure in December
Rosalia, WA
- Average pressure in December: 30.17"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is August (29.9"Hg).
Average wind speed in December
Rosalia, WA
- Average wind speed in December: 7.1mph
The windiest month (with the highest average wind speed) is March (8.8mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in December
Rosalia, WA
- Average humidity in December: 85%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is August (36%).
Average rainfall in December
Rosalia, WA
- Average rainfall in December: 0.79"
The wettest months (with the highest rainfall) are January and May (0.91").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in December
Rosalia, WA
- Average rainfall days in December: 6.5 days
The month with the highest number of rainy days is March (10.1 days).
The month with the least rainy days is July (3.5 days).
Average snowfall in December
Rosalia, WA
- Average snowfall in December: 2.91"
The month with the highest snowfall is February (3.82").
The months with the least snowfall are June, July, August and October (0").
Average snowfall days in December
Rosalia, WA
- Average snowfall days in December: 9.3 days
The month with the highest number of snowfall days is December (9.3 days).
The months with the least snowfall days are June, July, August and October (0 days).
Average daylight in December /
Average sunshine in December
Rosalia, WA
- Average daylight in December: 8h and 36min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in December: 4h and 18min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in December
Rosalia, WA
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is July (26.6 days).
The month with the least sunshine days is February (15.9 days).
Average UV index in December
Rosalia, WA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Rosalia, WA
- Average cloud cover in December: 55
The months with the most cloud cover are January and December (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in December
Rosalia, 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).
