December weather forecastUnderwood Heights, WA
December
Weather in December
The first month of the winter, December, is also an icy month in Underwood Heights, Washington, with an average temperature ranging between min 27°F (-2.8°C) and max 36°F (2.2°C).Temperature
December, characterized by an average high temperature of 36°F (2.2°C) and a low temperature of 27°F (-2.8°C), is generally the coldest month.Humidity
The months with the highest humidity are February and December, with an average relative humidity of 88%.Rainfall
In December, in Underwood Heights, the rain falls for 17.9 days. Throughout December, 5.08" (129mm) of precipitation is accumulated. In Underwood Heights, Washington, during the entire year, the rain falls for 159.7 days and collects up to 31.42" (798mm) of precipitation.Snowfall
Months with snowfall are January through March, November and December. In Underwood Heights, Washington, in December, snow falls for 4.1 days, with typically accumulated 3.66" (93mm) of snow. Throughout the year, there are 15.1 snowfall days, and 14.33" (364mm) of snow is accumulated.Daylight
December has the shortest days of the year in Underwood Heights, with an average of 8h and 42min of daylight.On the first day of December, sunrise is at 7:27 am and sunset at 4:23 pm. On the last day of the month, sunrise is at 7:46 am and sunset at 4:32 pm PST.
Sunshine
The average sunshine in December in Underwood Heights is 3.9h.UV index
The average daily maximum UV index in December is 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The UV index of 2 in December translates into these instructions:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Enhance your sun protection with tightly woven, yet airy clothing. Take into account! The reflection from snow can nearly double the Sun's UV radiation intensity.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Underwood Heights, WA
- Average high temperature in December: 36°F
The warmest month (with the highest average high temperature) is August (78.4°F).
The month with the lowest average high temperature is December (36°F).
- Average low temperature in December: 27°F
The month with the highest average low temperature is August (51.4°F).
The coldest month (with the lowest average low temperature) is December (27°F).
Average pressure in December
Underwood Heights, WA
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is August (29.97"Hg).
Average wind speed in December
Underwood Heights, WA
- Average wind speed in December: 5.2mph
The windiest month (with the highest average wind speed) is June (6.1mph).
The calmest month (with the lowest average wind speed) is October (4.8mph).
Average humidity in December
Underwood Heights, WA
- Average humidity in December: 88%
The months with the highest relative humidity are February and December (88%).
The month with the lowest relative humidity is July (59%).
Average rainfall in December
Underwood Heights, WA
- Average rainfall in December: 5.08"
The wettest month (with the highest rainfall) is January (5.67").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in December
Underwood Heights, WA
- Average rainfall days in December: 17.9 days
The month with the highest number of rainy days is March (20 days).
The month with the least rainy days is August (4.2 days).
Average snowfall in December
Underwood Heights, WA
- Average snowfall in December: 3.66"
The month with the highest snowfall is February (4.76").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Underwood Heights, WA
- Average snowfall days in December: 4.1 days
The month with the highest number of snowfall days is December (4.1 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
Underwood Heights, 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: 3h and 54min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Underwood Heights, WA
- Average sunshine days in December: 9.8 days
The month with the most sunshine days is July (25.4 days).
The month with the least sunshine days is March (8.4 days).
Average UV index in December
Underwood Heights, 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 and November (UV index 1).
Average cloud cover in December
Underwood Heights, WA
- Average cloud cover in December: 62
The months with the most cloud cover are January and February (Cloud cover 64).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in December
Underwood Heights, WA
- Average visibility in December: 4mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (4mi).
