December weather forecast and climate
Brentwood, CA

Scenic and organized home community in Brentwood City, California
Scenic and organized home community in Brentwood City, California

Weather in December

The first month of the winter, December, is still a cool month in Brentwood, California, with average temperature fluctuating between 41.7°F (5.4°C) and 55°F (12.8°C).

Temperature

December is the coldest month, with an average high-temperature of 55°F (12.8°C) and an average low-temperature of 41.7°F (5.4°C).

Humidity

In Brentwood, the average relative humidity is 71%.

Rainfall

In December, in Brentwood, California, the rain falls for 9.3 days. Throughout December, 1.57" (40mm) of precipitation is accumulated. Throughout the year, in Brentwood, there are 62 rainfall days, and 10.16" (258mm) of precipitation is accumulated.

Snowfall

The only month with snowfall is December. December has the most snowfall days of the year in Brentwood. Snow falls for 0.1 days.

Daylight

The month with the shortest days is December, with an average of 9.6h of daylight.

Sunshine

December has the least sunshine of the year, with an average of 5.8h of sunshine.

UV index

Months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index of 3 to 5 symbolizes a medium health hazard from the exposure to the Sun's UV radiation for the ordinary person.
Note: The daily maximum UV index of 3 in December interpret into the following advice:
Take precautions - Protection against sunburn is recommended. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.
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FAQ

What is the coldest month in Brentwood?

December is the coldest month, with an average high-temperature of 55°F (12.8°C) and an average low-temperature of 41.7°F (5.4°C).

What is the temperature in December in Brentwood?

In December, in Brentwood, California, the average high-temperature is 55°F (12.8°C), and the average low-temperature is 41.7°F (5.4°C).

What is the average humidity in December in Brentwood?

In December, the average relative humidity in Brentwood is 71%.

How many days does it rain in December in Brentwood?

In December, in Brentwood, the rain falls for 9.3 days. Throughout December, 1.57" (40mm) of precipitation is accumulated.

When does it start snowing in Brentwood?

December is the first month it typically snows in Brentwood. Throughout December, there are 0.1 snowfall days.

When does it snow the most in Brentwood?

The month with the most snowfall days in Brentwood is December when snow falls for 0.1 days.

What is the month with the shortest days in Brentwood?

The month with the shortest days in Brentwood, California, is December, with an average of 9.6h of daylight.

How many hours of daylight does Brentwood have in December?

In December, the average length of the day in Brentwood, California, is 9.6h.

What is the month with the least sunshine in Brentwood?

December has the least sunshine of the year in Brentwood, with an average of 5.8h of sunshine.

How long on average sun shines in December in Brentwood?

The average sunshine in December in Brentwood, California, is 5.8h.

What is the month with the lowest UV index in Brentwood?

January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index.

How high is the UV index in December in Brentwood?

The average daily maximum UV index in December in Brentwood, California, is 3. A UV Index estimate of 3 to 5 represents a moderate vulnerability from the exposure to the Sun's UV radiation.

Average temperature in December
Brentwood, CA

Average temperature in December - Brentwood, CA
  • Average high temperature in December: 12.8°C

The warmest month (with the highest average high temperature) is July (31.4°C).
The month with the lowest average high temperature is December (12.8°C).

  • Average low temperature in December: 5.4°C

The month with the highest average low temperature is September (14.3°C).
The coldest month (with the lowest average low temperature) is January (5.3°C).

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Average pressure in December
Brentwood, CA

Average pressure in December - Brentwood, CA
  • Average pressure in December: 1019.7mbar

The month with the highest atmospheric pressure is January (1020.6mbar).
The month with the lowest atmospheric pressure is June (1012.9mbar).

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Average wind speed in December
Brentwood, CA

Average wind speed in December - Brentwood, CA
  • Average wind speed in December: 8km/h

The windiest month (with the highest average wind speed) is June (12.5km/h).
The calmest months (with the lowest average wind speed) are January and November (7.3km/h).

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Average humidity in December
Brentwood, CA

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%).

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Average rainfall in December
Brentwood, CA

Average rainfall in December - Brentwood, CA
  • Average rainfall in December: 40mm

The wettest month (with the highest rainfall) is February (53mm).
The driest months (with the least rainfall) are July and August (1mm).

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Average rainfall days in December
Brentwood, CA

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).

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Average snowfall days in December
Brentwood, CA

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).
Months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).

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Average daylight in December /
Average sunshine in December
Brentwood, CA

Average daylight in December / Average sunshine in December - Brentwood, CA
  • Average daylight in December: 9.6h

The month with the longest days is June (Average daylight: 14.8h).
The month with the shortest days is December (Average daylight: 9.6h).

  • Average sunshine in December: 5.8h

The month with the most sunshine is July (Average sunshine: 12.1h).
The month with the least sunshine is December (Average sunshine: 5.8h).

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Average sunshine days in December
Brentwood, CA

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).

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Average UV index in December
Brentwood, CA

Average UV index in December - Brentwood, CA
  • Average UV index in December: 3

Months with the highest UV index are June, July and August (UV index 6).
Months with the lowest UV index are January, February, November and December (UV index 3).

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Average cloud cover in December
Brentwood, CA

Average cloud cover in December - Brentwood, CA
  • Average cloud cover in December: 35

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).

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Average visibility in December
Brentwood, CA

Average visibility in December - Brentwood, CA
  • Average visibility in December: 9km

Months with the highest visibility are May, June, July, August, September, October and November (10km).
Months with the lowest visibility are January, February, March, April and December (9km).

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