January weather forecast and climate
San Diego, CA

The view of Coronado Island in San Diego, California, from across a water body on a sidewalk, with a row of palm trees
The view of Coronado Island in San Diego, California, from across a water body on a sidewalk, with a row of palm trees
January is the wettest month with 2.1" (53.3mm) of rainfall in San Diego as the mild winter continues its peaceful march. The average low temperature is 49°F (9.4°C), but it is rare to see the nights touch 40°F (4.4°C). The days are on the shorter side at 10 hours, but the temperatures lie in the comfortable range of 60°F (15.6°C) to 70°F (21.1°C).
Though it is a little wet, the conditions around New Year are pleasant with the humidity at 63%, the lowest of the year. With the daily sunshine of 8 hours and a rain jacket for protection, San Diego is charming for outdoor activities.

What is the temperature in January in San Diego?

The average high-temperature, in January, is 65.1°F (18.4°C), while the average low-temperature is 48.9°F (9.4°C).

How many days does it rain in January in San Diego?

In San Diego, California, in January, during 6.7 rainfall days, typically 2.1" (53mm) of precipitation is accumulated.

What is the wettest month in San Diego?

January is the month with the most rainfall in San Diego. Rain falls for 6.7 days and accumulates 2.1" (53mm) of precipitation.
Average temperature in January - San Diego, CA
  • Average high temperature in January: 65.1°F

The warmest month (with the highest average high temperature) is August (76.4°F).
The month with the lowest average high temperature is December (64.7°F).

  • Average low temperature in January: 49°F

The month with the highest average low temperature is August (66.7°F).
The coldest month (with the lowest average low temperature) is December (48.4°F).

Average humidity in January - San Diego, CA
  • Average humidity in January: 63.1%

The month with the highest relative humidity is July (74.6%).
The month with the lowest relative humidity is January (63.1%).

Average rainfall in January - San Diego, CA
  • Average rainfall in January: 2.1"

The wettest month (with the highest rainfall) is January (2.1").
The driest month (with the lowest rainfall) is July (0").

Average rainfall days in January - San Diego, CA
  • Average rainfall days in January: 6.7 days

The month with the highest number of rainy days is February (7.1 days).
The month with the lowest number of rainy days is August (0.4 days).

Average sea temperature in January - San Diego, CA
  • Average sea temperature in January: 59.2°F

The best month for swimming (with the highest average sea temperature) is August (67.9°F).
The coldest month (with the lowest average sea temperature) is February (58.7°F).

Average daylight in January / Average sunshine in January - San Diego, CA
  • Average daylight in January: 10.3h

The month with the longest days is June (Average daylight: 14.3h).
The month with shortest days is December (Average daylight: 10h).

  • Average sunshine in January: 7.7h

The month with most sunshine is July (Average sunshine: 9.8h).
The month with least sunshine is December (Average sunshine: 7.5h).

Average UV index in January - San Diego, CA
  • Average UV index in January: 3

Months with the highest UV index are June, July and August (UV index 10).
Months with the lowest UV index are January and December (UV index 3).

deutscheenglishespañolрусский中文