January weather forecastSonoma, CA
January
Weather in January
Kicking off the year in Sonoma, California, the weather in January ushers in mild winter temperatures. The days tend to be cooler, leading to a chilly ambiance. Weather patterns fluctuate frequently with a larger portion of the month shrouded in cloud cover. Significant rainfall can be expected, with January recording one of the highest amounts. Despite the cooler climate and ample cloud cover, daylight persists for approximately 9.9 hours daily.Temperature
Sonoma, California, greets January with an average high-temperature of a refreshing 56.3°F (13.5°C), marking a slight deviation from the preceding month. During January, Sonoma experiences a consistent low-temperature average of 42.1°F (5.6°C).Humidity
In Sonoma, the average relative humidity in January is 74%.Rainfall
In Sonoma, during January, the rain falls for 10.4 days and regularly aggregates up to 2.87" (73mm) of precipitation. Throughout the year, there are 73.3 rainfall days, and 15.47" (393mm) of precipitation is accumulated.Daylight
In Sonoma, the average length of the day in January is 9h and 52min.On the first day of the month, sunrise is at 7:26 am and sunset at 5:00 pm. On the last day of January, sunrise is at 7:15 am and sunset at 5:30 pm PST.
Sunshine
In January, the average sunshine is 5.7h.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 health hazard from unsafe exposure to UV radiation for the average person.Note: A daily maximum UV index of 3 in January translates into the following instructions:
Make use of precautions - Shielding skin and eyes from injury is a requirement. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
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 pressure in January
Sonoma, CA
- Average pressure in January: 30.13"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in January
Sonoma, CA
- Average wind speed in January: 4.8mph
The windiest month (with the highest average wind speed) is May (6.2mph).
The calmest month (with the lowest average wind speed) is November (4.4mph).
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").
The driest months (with the least 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 least rainy days is August (0.8 days).
Average daylight in January /
Average sunshine in January
Sonoma, CA
- Average daylight in January: 9h and 54min
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 January: 5h and 42min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in January
Sonoma, CA
- Average sunshine days in January: 19.9 days
The month with the most sunshine days is July (28.7 days).
The month with the least sunshine days is March (16.1 days).
Average UV index in January
Sonoma, CA
- Average UV index in January: 3
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in January
Sonoma, CA
- Average cloud cover in January: 37
The month with the most cloud cover is March (Cloud cover 40).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility in January
Sonoma, CA
- Average visibility in January: 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).
