Happy New Year! San Diego weather in January frequently offers warm days and cold nights. Although, I can tell you from first hand experience running a tour business serving guests from around the world, most travelers get a good laugh when we use the word ‘cold’ in San Diego.
To me, anytime it goes below freezing at 32 degrees Fahrenheit, it’s cold! Well, January is the only month of the year, historically, where temperatures tracked at the San Diego Airport, just a mile away from downtown’s tourist attractions, have gone below freezing. (Yes, woe is us in San Diego.) Officially, it’s only gone below freezing four times in our history, always in January. The coldest was back in 1913 when it hit 25 degrees.
The cold temperatures come during clear nights when there are no clouds to keep the previous day’s heat from escaping into the atmosphere. But, it’s those same clear skies that bring us warm days. We frequently see days with highs in the 70s and even 80s. The highest was back in 1953 when we reached a high temperature in San Diego during January of 88 degrees.
As for the average highs and lows in San Diego during January, they are 65 degrees and 50 degrees respectively. (For foreigners, that’s about 18 degrees Celsius and 10 degrees Celsius respectively.)
January is the wettest month of the year, with an average of 7 days of rain. However, on the bright side, it’s also the fourth sunniest month of the year in San Diego.
So, that’s what you can expect in San Diego for weather in January. Visitors who want to learn more about weather in San Diego throughout the year can visit my San Diego Travel Guide. For locals wanting to learn more about San Diego’s weather history, visit the NOAA web site. I also highly recommend subscribing to the Union Tribune newspaper where weatherman Robert Krier answers readers questions about weather in San Diego.