December weather forecastTualatin, OR
December
Weather in December
December welcomes winter in full force in Tualatin, with the lowest average temperatures for the year down to 34.5°F (1.4°C). The days are shortest in this month, restricting outdoor activities as well as reducing visibility. While snowfall does occur, it remains at minimal levels of 0.43" (11mm), adding to the seasonal feel. The Roaring Lion month concludes with high levels of relative humidity and rampant rainfall happening. As the year comes full circle, anticipate similar weather patterns until the New Year brings along milder temperatures and less precipitation.Temperature
With an average high-temperature of 44.1°F (6.7°C) and an average low-temperature of 34.5°F (1.4°C), December is the coldest month.Humidity
The months with the highest humidity are January, February and December, with an average relative humidity of 84%.Rainfall
December is the month with the most rainfall. Rain falls for 18.9 days and accumulates 4.57" (116mm) of precipitation.Snowfall
Months with snowfall are January through March, November and December. In Tualatin, in December, snow falls for 0.9 days, with typically accumulated 0.43" (11mm) of snow. Throughout the year, there are 6.5 snowfall days, and 3.94" (100mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 8h and 48min of daylight.On the first day of the month, sunrise is at 7:31 am and sunset at 4:29 pm. On the last day of December, sunrise is at 7:50 am and sunset at 4:38 pm PST.
Sunshine
The average sunshine in December is 4.2h.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 estimate of 2, and below, represents a low threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: In December, a regular UV index of 2 translates into these guidelines:
While most individuals can withstand prolonged sun exposure, it is imperative that babies, children, and those with sensitive skin always be shielded. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Tualatin, OR
- Average high temperature in December: 44.1°F
The warmest month (with the highest average high temperature) is August (82°F).
The month with the lowest average high temperature is December (44.1°F).
- Average low temperature in December: 34.5°F
The month with the highest average low temperature is August (55°F).
The coldest month (with the lowest average low temperature) is December (34.5°F).
Average pressure in December
Tualatin, OR
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in December
Tualatin, OR
- Average wind speed in December: 5.2mph
The windiest month (with the highest average wind speed) is January (5.5mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in December
Tualatin, OR
- Average humidity in December: 84%
The months with the highest relative humidity are January, February and December (84%).
The month with the lowest relative humidity is August (63%).
Average rainfall in December
Tualatin, OR
- Average rainfall in December: 4.57"
The wettest month (with the highest rainfall) is December (4.57").
The driest month (with the least rainfall) is July (0.31").
Average rainfall days in December
Tualatin, OR
- Average rainfall days in December: 18.9 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (4.8 days).
Average snowfall in December
Tualatin, OR
- Average snowfall in December: 0.43"
The month with the highest snowfall is February (1.57").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Tualatin, OR
- Average snowfall days in December: 0.9 days
The month with the highest number of snowfall days is February (2.3 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
Tualatin, OR
- Average daylight in December: 8h and 48min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in December: 4h and 12min
The month with the most sunshine is August (Average sunshine: 11h and 0min).
The month with the least sunshine is February (Average sunshine: 4h and 6min).
Average sunshine days in December
Tualatin, OR
- Average sunshine days in December: 10.4 days
The month with the most sunshine days is July (25 days).
The month with the least sunshine days is February (8.6 days).
Average UV index in December
Tualatin, OR
- 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, November and December (UV index 2).
Average cloud cover in December
Tualatin, OR
- Average cloud cover in December: 56
The month with the most cloud cover is February (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in December
Tualatin, OR
- Average visibility in December: 5mi
The months with the highest visibility are July, August and September (6mi).
The months with the lowest visibility are January, February, March, April, May, June, October, November and December (5mi).
