December weather forecastWaterville, WA
December
Weather in December
December, the first month of the winter in Waterville, is still a freezing cold month, with temperature in the range of an average high of 30.2°F (-1°C) and an average low of 19°F (-7.2°C).Temperature
The lowest temperatures are recorded in December, with averages reaching a high of 30.2°F (-1°C) and a low of 19°F (-7.2°C).Humidity
In Waterville, the average relative humidity in December is 88%.Rainfall
December is the month with the most rainfall. Rain falls for 7.5 days and accumulates 1.65" (42mm) of precipitation.Snowfall
January through April, September through December are months with snowfall. The month with the most snowfall is December, when snow falls for 11.9 days and typically aggregates up to 9.06" (230mm) of snow.Daylight
With an average of 8h and 30min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:28 am and sunset at 4:10 pm. On the last day of December, sunrise is at 7:48 am and sunset at 4:18 pm PST.
Sunshine
In December, the average sunshine is 4.5h.UV index
The months with the lowest UV index are January through March, October through December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index, 2 during December, leads to the following recommendations:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Waterville, WA
- Average high temperature in December: 30.2°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is December (30.2°F).
- Average low temperature in December: 19°F
The month with the highest average low temperature is August (55.8°F).
The coldest months (with the lowest average low temperature) are January and December (19°F).
Average pressure in December
Waterville, WA
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is August (29.93"Hg).
Average wind speed in December
Waterville, WA
- Average wind speed in December: 3.5mph
The windiest month (with the highest average wind speed) is June (6.1mph).
The calmest months (with the lowest average wind speed) are January and December (3.5mph).
Average humidity in December
Waterville, WA
- Average humidity in December: 88%
The month with the highest relative humidity is January (90%).
The months with the lowest relative humidity are July and August (43%).
Average rainfall in December
Waterville, WA
- Average rainfall in December: 1.65"
The wettest month (with the highest rainfall) is December (1.65").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in December
Waterville, WA
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is March (12.8 days).
The month with the least rainy days is August (3.8 days).
Average snowfall in December
Waterville, WA
- Average snowfall in December: 9.06"
The month with the highest snowfall is December (9.06").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days in December
Waterville, WA
- Average snowfall days in December: 11.9 days
The month with the highest number of snowfall days is January (12 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Waterville, WA
- Average daylight in December: 8h and 30min
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 30min).
- Average sunshine in December: 4h and 30min
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 6min).
Average sunshine days in December
Waterville, WA
- Average sunshine days in December: 15.2 days
The month with the most sunshine days is July (25.7 days).
The month with the least sunshine days is March (13.2 days).
Average UV index in December
Waterville, WA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in December
Waterville, WA
- Average cloud cover in December: 52
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July and August (Cloud cover 12).
Average visibility in December
Waterville, WA
- Average visibility in December: 4mi
The months with the highest visibility are April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (4mi).





