December weather forecastBrentwood, CA
December
Weather in December
The first month of the winter, December, is still a cool month in Brentwood, California, with temperature in the range of an average low of 41.7°F (5.4°C) and an average high of 55°F (12.8°C).Temperature
With its high average temperature of 55°F (12.8°C) and a low of 41.7°F (5.4°C), December is regarded as the coldest month.Humidity
The average relative humidity in December is 71%.Rainfall
In Brentwood, in December, it is raining for 9.3 days, with typically 1.57" (40mm) of accumulated precipitation. In Brentwood, during the entire year, the rain falls for 62 days and collects up to 10.16" (258mm) of precipitation.Snowfall
December is the only month when snow falls in Brentwood. The month with the most snowfall days is December, when snow falls for 0.1 days.Daylight
With an average of 9h and 36min of daylight, December has the shortest days of the year.On the first day of December in Brentwood, sunrise is at 7:04 am and sunset at 4:47 pm. On the last day of the month, sunrise is at 7:22 am and sunset at 4:57 pm PST.
Sunshine
With an average of 5.8h of sunshine, December has the least sunshine of the year in Brentwood.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 3 in December converts into the following recommendations:
Prioritize safety - The need to safeguard skin and eyes from harm is emphasized. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Remember this! The UV radiation of the Sun can be nearly doubled by the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Brentwood, CA
- Average high temperature in December: 55°F
The warmest month (with the highest average high temperature) is July (88.5°F).
The month with the lowest average high temperature is December (55°F).
- Average low temperature in December: 41.7°F
The month with the highest average low temperature is September (57.7°F).
The coldest month (with the lowest average low temperature) is January (41.5°F).
Average pressure in December
Brentwood, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Brentwood, CA
- Average wind speed in December: 5mph
The windiest month (with the highest average wind speed) is June (7.8mph).
The calmest months (with the lowest average wind speed) are January and November (4.5mph).
Average humidity in December
Brentwood, CA
- Average humidity in December: 71%
The month with the highest relative humidity is January (74%).
The month with the lowest relative humidity is September (52%).
Average rainfall in December
Brentwood, CA
- Average rainfall in December: 1.57"
The wettest month (with the highest rainfall) is February (2.09").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in December
Brentwood, CA
- Average rainfall days in December: 9.3 days
The month with the highest number of rainy days is March (12.3 days).
The month with the least rainy days is August (0.8 days).
Average snowfall days in December
Brentwood, CA
- Average snowfall days in December: 0.1 days
The month with the highest number of snowfall days is December (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in December /
Average sunshine in December
Brentwood, CA
- Average daylight in December: 9h and 36min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 48min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in December
Brentwood, CA
- Average sunshine days in December: 21.1 days
The month with the most sunshine days is August (29.8 days).
The month with the least sunshine days is March (17.7 days).
Average UV index in December
Brentwood, CA
- Average UV index in December: 3
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
Brentwood, CA
- Average cloud cover in December: 35
The months with the most cloud cover are March and December (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 5).
Average visibility in December
Brentwood, CA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
