December weather forecastPleasant Hill, OR
December
Weather in December
The first month of the winter, December, is also a frosty month in Pleasant Hill, Oregon, with an average temperature varying between 33.8°F (1°C) and 46°F (7.8°C).Temperature
Temperature readings reach their annual highs in December, averaging 46°F (7.8°C) and a minimum average of 33.8°F (1°C).Humidity
The months with the highest humidity are January through March and December, with an average relative humidity of 86%.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 April, November and December. In December, it is snowing for 0.8 days. Throughout December, 0.43" (11mm) of snow is accumulated. In Pleasant Hill, during the entire year, snow falls for 6.6 days and aggregates up to 5" (127mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 0min of daylight.On the first day of the month, sunrise is at 7:27 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:46 am and sunset at 4:44 pm PST.
Sunshine
In December, the average sunshine is 4.2h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low health risk from exposure to the Sun's UV rays for average individuals.Note: In December, the average maximum UV index of 2 translates into the following recommendations:
Sun exposure does not present considerable issues for many, yet infants, fair-skinned people, and children necessitate constant protection. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Pleasant Hill, OR
- Average high temperature in December: 46°F
The warmest month (with the highest average high temperature) is August (80.4°F).
The month with the lowest average high temperature is December (46°F).
- Average low temperature in December: 33.8°F
The month with the highest average low temperature is August (49.6°F).
The coldest month (with the lowest average low temperature) is December (33.8°F).
Average pressure in December
Pleasant Hill, OR
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in December
Pleasant Hill, OR
- Average wind speed in December: 4.3mph
The windiest months (with the highest average wind speed) are January and March (4.4mph).
The calmest months (with the lowest average wind speed) are August and September (3.5mph).
Average humidity in December
Pleasant Hill, OR
- Average humidity in December: 86%
The months with the highest relative humidity are January, February, March and December (86%).
The month with the lowest relative humidity is August (69%).
Average rainfall in December
Pleasant Hill, 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 (0.2").
Average rainfall days in December
Pleasant Hill, OR
- Average rainfall days in December: 18.5 days
The month with the highest number of rainy days is March (20.3 days).
The month with the least rainy days is August (3.5 days).
Average snowfall in December
Pleasant Hill, OR
- Average snowfall in December: 0.43"
The month with the highest snowfall is February (2.72").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Pleasant Hill, OR
- Average snowfall days in December: 0.8 days
The month with the highest number of snowfall days is February (2.5 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
Pleasant Hill, OR
- Average daylight in December: 9h and 0min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- 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
Pleasant Hill, OR
- Average sunshine days in December: 11.2 days
The month with the most sunshine days is August (25.6 days).
The month with the least sunshine days is February (9.1 days).
Average UV index in December
Pleasant Hill, 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
Pleasant Hill, OR
- Average cloud cover in December: 57
The month with the most cloud cover is March (Cloud cover 60).
The month with the least cloud cover is August (Cloud cover 23).
Average visibility in December
Pleasant Hill, OR
- Average visibility in December: 4mi
The months with the highest visibility are June, July, August, September and October (5mi).
The months with the lowest visibility are January, February, March, April, May, November and December (4mi).





