December weather forecastDayton, WA
December
Weather in December
The first month of the winter, December, is also a wintry month in Dayton, Washington, with an average temperature varying between 36.5°F (2.5°C) and 25.7°F (-3.5°C).Temperature
With average temperatures fluctuating between a high of 36.5°F (2.5°C) and a low of 25.7°F (-3.5°C), December stands out as the coldest month.Humidity
The average relative humidity in December is 80%.Rainfall
December is the month with the most rainfall. Rain falls for 13.6 days and accumulates 2.05" (52mm) of precipitation.Snowfall
Months with snowfall are January through May, September, November and December. In Dayton, during December, snow falls for 7.6 days and regularly aggregates up to 3.31" (84mm) of snow. Throughout the year, in Dayton, there are 28.4 snowfall days, and 13.58" (345mm) of snow is accumulated.Daylight
With an average of 8h and 42min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:15 am and sunset at 4:07 pm. On the last day of December, sunrise is at 7:34 am and sunset at 4:15 pm PST.
Sunshine
In December, the average sunshine in Dayton is 5.3h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a low health risk from unprotected exposure to Sun's UV rays for average individuals.Note: The UV index of 2 during December leads to these advisories:
Prolonged sun exposure should always be prevented in babies, children, and those with sensitive skin. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. On your guard! Snow's reflection can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Dayton, WA
- Average high temperature in December: 36.5°F
The warmest month (with the highest average high temperature) is August (83.7°F).
The month with the lowest average high temperature is December (36.5°F).
- Average low temperature in December: 25.7°F
The month with the highest average low temperature is August (60.3°F).
The coldest month (with the lowest average low temperature) is December (25.7°F).
Average pressure in December
Dayton, 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
Dayton, WA
- Average wind speed in December: 6.8mph
The windiest month (with the highest average wind speed) is April (8.6mph).
The calmest month (with the lowest average wind speed) is September (6.3mph).
Average humidity in December
Dayton, WA
- Average humidity in December: 80%
The month with the highest relative humidity is January (81%).
The month with the lowest relative humidity is August (39%).
Average rainfall in December
Dayton, WA
- Average rainfall in December: 2.05"
The wettest month (with the highest rainfall) is December (2.05").
The driest months (with the least rainfall) are July and August (0.35").
Average rainfall days in December
Dayton, WA
- Average rainfall days in December: 13.6 days
The month with the highest number of rainy days is March (17.6 days).
The month with the least rainy days is July (5.3 days).
Average snowfall in December
Dayton, WA
- Average snowfall in December: 3.31"
The month with the highest snowfall is February (4.53").
The months with the least snowfall are June, July, August and October (0").
Average snowfall days in December
Dayton, WA
- Average snowfall days in December: 7.6 days
The month with the highest number of snowfall days is February (7.7 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Dayton, WA
- Average daylight in December: 8h and 42min
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 18min
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: 5h and 6min).
Average sunshine days in December
Dayton, WA
- Average sunshine days in December: 12.8 days
The month with the most sunshine days is July (24 days).
The month with the least sunshine days is February (10 days).
Average UV index in December
Dayton, 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
Dayton, WA
- Average cloud cover in December: 45
The months with the most cloud cover are January and February (Cloud cover 47).
The months with the least cloud cover are July and August (Cloud cover 11).
Average visibility in December
Dayton, WA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





