December weather forecastLake Oswego, OR
December
Weather in December
December finds Lake Oswego fully entrenched in the grip of winter, sporting temperatures dropping to an average high of 44.4°F (6.9°C). The noticeable drop from November's temperatures reinforces the winter's peak arrival. While rain prevails as the main form of precipitation, it's not unusual to see December dusted with its first few snowflakes. Despite the waning sunlight and daylight, the holiday spirit imbued within the cool, crisp air forms the perfect backdrop for joyful winter celebrations. With its frost-kissed landscapes, Lake Oswego in December is a splendid mix of wintry elegance and holiday festivities.Temperature
In Lake Oswego, the lowest temperatures are generally noted in December, averaging a high of 44.4°F (6.9°C) and a low of 34.7°F (1.5°C).Humidity
In December, the average relative humidity is 83%.Rainfall
December is the month with the most rainfall. Rain falls for 18.5 days and accumulates 4.57" (116mm) of precipitation.Snowfall
Months with snowfall are January through March, November and December. In Lake Oswego, during December, snow falls for 0.8 days and regularly aggregates up to 0.39" (10mm) of snow. Throughout the year, there are 6.5 snowfall days, and 4.13" (105mm) of snow is accumulated.Daylight
With an average of 8h and 48min of daylight, December has the shortest days of the year in Lake Oswego.On the first day of December, sunrise is at 7:30 am and sunset at 4:29 pm. On the last day of the month, sunrise is at 7:50 am and sunset at 4:37 pm PST.
Sunshine
In Lake Oswego, the average sunshine in December is 4.4h.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 minimal health vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum UV index of 2 during December leads to these instructions:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Lake Oswego, OR
- Average high temperature in December: 44.4°F
The warmest month (with the highest average high temperature) is August (81.7°F).
The month with the lowest average high temperature is December (44.4°F).
- Average low temperature in December: 34.7°F
The month with the highest average low temperature is August (54.5°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in December
Lake Oswego, OR
- Average pressure in December: 30.1"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
Lake Oswego, OR
- Average wind speed in December: 5.7mph
The windiest month (with the highest average wind speed) is January (6mph).
The calmest month (with the lowest average wind speed) is August (3.7mph).
Average humidity in December
Lake Oswego, OR
- Average humidity in December: 83%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is August (63%).
Average rainfall in December
Lake Oswego, 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
Lake Oswego, OR
- Average rainfall days in December: 18.5 days
The month with the highest number of rainy days is March (20.4 days).
The month with the least rainy days is July (4.8 days).
Average snowfall in December
Lake Oswego, OR
- Average snowfall in December: 0.39"
The month with the highest snowfall is March (1.46").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Lake Oswego, OR
- Average snowfall days in December: 0.8 days
The month with the highest number of snowfall days is February (2.3 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
Lake Oswego, 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 24min
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 12min).
Average sunshine days in December
Lake Oswego, OR
- Average sunshine days in December: 10.9 days
The month with the most sunshine days is July (23.9 days).
The month with the least sunshine days is February (8.3 days).
Average UV index in December
Lake Oswego, 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
Lake Oswego, OR
- Average cloud cover in December: 55
The month with the most cloud cover is February (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 22).
Average visibility in December
Lake Oswego, OR
- Average visibility in December: 5mi
The months with the highest visibility are July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, April, May, June, November and December (5mi).
