December weather forecastCascadia, OR
December
Weather in December
December, the first month of the winter in Cascadia, is still a chilly month, with temperature in the range of an average high of 44.4°F (6.9°C) and an average low of 32.9°F (0.5°C).Temperature
December is the coldest month, with the temperature often reaching an average high of 44.4°F (6.9°C) and an average low of 32.9°F (0.5°C).Humidity
February, March and December, with an average relative humidity of 86%, are the most humid months.Rainfall
The month with the most rainfall in Cascadia is December, when the rain falls for 18.9 days and typically aggregates up to 5.47" (139mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In Cascadia, in December, snow falls for 1 days, with typically accumulated 0.47" (12mm) of snow. In Cascadia, during the entire year, snow falls for 7.9 days and aggregates up to 7.76" (197mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 54min of daylight.On the first day of the month, sunrise is at 7:26 am and sunset at 4:31 pm. On the last day of December, sunrise is at 7:45 am and sunset at 4:40 pm PST.
Sunshine
The average sunshine in December is 4.3h.UV index
In Cascadia, 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 average person.Note: In December, the maximum UV index of 2 translates into these guidelines:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized. Take careful note! The UV radiation of the Sun can be nearly doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Cascadia, OR
- Average high temperature in December: 44.4°F
The warmest month (with the highest average high temperature) is August (79.5°F).
The month with the lowest average high temperature is December (44.4°F).
- Average low temperature in December: 32.9°F
The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (32.9°F).
Average pressure in December
Cascadia, OR
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in December
Cascadia, OR
- Average wind speed in December: 5mph
The windiest month (with the highest average wind speed) is January (5.1mph).
The calmest month (with the lowest average wind speed) is August (3.7mph).
Average humidity in December
Cascadia, OR
- Average humidity in December: 86%
The months with the highest relative humidity are February, March and December (86%).
The month with the lowest relative humidity is August (66%).
Average rainfall in December
Cascadia, OR
- Average rainfall in December: 5.47"
The wettest month (with the highest rainfall) is December (5.47").
The driest month (with the least rainfall) is July (0.24").
Average rainfall days in December
Cascadia, OR
- Average rainfall days in December: 18.9 days
The month with the highest number of rainy days is March (21.1 days).
The month with the least rainy days is July (4.1 days).
Average snowfall in December
Cascadia, OR
- Average snowfall in December: 0.47"
The month with the highest snowfall is February (3.7").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Cascadia, OR
- Average snowfall days in December: 1 days
The month with the highest number of snowfall days is February (3.4 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
Cascadia, OR
- Average daylight in December: 8h and 54min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 4h and 18min
The month with the most sunshine is August (Average sunshine: 11h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 6min).
Average sunshine days in December
Cascadia, OR
- Average sunshine days in December: 11 days
The month with the most sunshine days is July (25.7 days).
The month with the least sunshine days is February (8.4 days).
Average UV index in December
Cascadia, OR
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in December
Cascadia, OR
- Average cloud cover in December: 56
The months with the most cloud cover are February and March (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 19).
Average visibility in December
Cascadia, OR
- Average visibility in December: 5mi
The month with the highest visibility is August (6mi).
The months with the lowest visibility are February and April (4mi).
