San Francisco Weather in January
The San Francisco Weather in January is characterized by the month being the rainiest month of the year. Nearly five inches of rain fall during January, but before you get discouraged, you should recognize that rain only falls on 1/3 of the days. Moreover, the sun actually shines a fair amount during the month, for a total of nearly 200 hours, and the month is actually less cloudy than it is in November and December.
As is the case with all the “rainy” months of the year in San Francisco, much depends on your luck and the year that you come. If you are unlucky, you may come in the middle of a rainy spell that can go on without much break for several days. On the other hand, you may come during one of the years with there is a long dry-spell that begins in early January and continues for nearly the month.
In January, the average high temperature in San Francisco is 58, and the average low is 46 degrees. The record low is 27, and the record high is 79. Try comparing these averages with anywhere else in the country, and you will appreciate why it is such a pleasure to live in San Francisco.
It is interesting to compare the temperatures in January to those in July, where the average high temperature is 68 (just 10 degrees higher than in January) and the average low temperature is 54 (just eight degrees higher). As you can see, the temperature variations in the San Francisco reflect very little change from season to season.
This is because San Francisco is surrounded on three sides by water. As a result, the climate and weather in San Francisco is directly influenced by the cool currents of the Pacific. This keeps temperature variations to a minimum and results in a climate that is moderate year round.