Sonoma
California, USA
Long-term weather forecast
Long-term weather forecast

January weather forecast and climate
Sonoma, CA

Neat rows of vines in a vineyard farm in Sonoma, California, the sun rays beaming through the cloudy sunset sky, and distant hilly silhouettes
Neat rows of vines in a vineyard farm in Sonoma, California, the sun rays beaming through the cloudy sunset sky, and distant hilly silhouettes
January in Sonoma, California, is a mild winter month, with temperature in the range of an average low of 42.1°F (5.6°C) and an average high of 56.3°F (13.5°C).

Temperature

In January, the average high-temperature is almost the same as in December - a mild 56.3°F (13.5°C). In January, the average low-temperature is 42.1°F (5.6°C).

Humidity

The average relative humidity in Sonoma is 74%.

Rainfall

In Sonoma, in January, it is raining for 10.4 days, with typically 2.87" (73mm) of accumulated precipitation. In Sonoma, California, during the entire year, the rain falls for 73.3 days and collects up to 15.47" (393mm) of precipitation.

Daylight

In January, the average length of the day in Sonoma is 9.9h.

Sunshine

The average sunshine in Sonoma, California, is 5.7h.

UV index

January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in Sonoma. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to the UV radiation for the ordinary person.
Note: The average daily UV index of 3 in January transform into the following instructions:
Take precautions - Protection against the skin and eye damage is obliged. 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.

What is the temperature in January in Sonoma?

The average high-temperature, in January, is 56.3°F (13.5°C), while the average low-temperature is 42.1°F (5.6°C).

What is the average humidity in January in Sonoma?

In Sonoma, California, the average relative humidity in January is 74%.

How much does it rain in Sonoma in January?

In Sonoma, in January, during 10.4 rainfall days, 2.87" (73mm) of precipitation is typically accumulated.

How many hours of daylight does Sonoma have in January?

The average length of the day in January in Sonoma is 9.9h.

How long on average sun shines in January in Sonoma?

In January, the average sunshine in Sonoma is 5.7h.

What are the months with the lowest UV index in Sonoma?

Months with the lowest UV index in Sonoma, California, are January, February, November and December, with an average maximum UV index of 3.

How high is the UV index in January in Sonoma?

In Sonoma, California, the average daily maximum UV index in January is 3. A UV Index value of 3 to 5 symbolizes a medium hazard to health from the exposure to the Sun's UV rays.
Average temperature in January - Sonoma, CA
  • Average high temperature in January: 56.3°F

The warmest month (with the highest average high temperature) is August (82.9°F).
The month with the lowest average high temperature is December (55°F).

  • Average low temperature in January: 42.1°F

The month with the highest average low temperature is August (54.9°F).
The coldest month (with the lowest average low temperature) is December (41.4°F).

Average humidity in January - Sonoma, CA
  • Average humidity in January: 74%

The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is September (59%).

Average rainfall in January - Sonoma, CA
  • Average rainfall in January: 2.87"

The wettest month (with the highest rainfall) is February (3.43").
Driest months (with the lowest rainfall) are July and August (0.04").

Average rainfall days in January - Sonoma, CA
  • Average rainfall days in January: 10.4 days

The month with the highest number of rainy days is March (13.4 days).
The month with the lowest number of rainy days is August (0.8 days).

Average daylight in January / Average sunshine in January - Sonoma, CA
  • Average daylight in January: 9.9h

The month with the longest days is June (Average daylight: 14.8h).
The month with shortest days is December (Average daylight: 9.5h).

  • Average sunshine in January: 5.7h

The month with most sunshine is July (Average sunshine: 12h).
The month with least sunshine is December (Average sunshine: 5.6h).

Average UV index in January - Sonoma, CA
  • Average UV index in January: 3

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