San Francisco weather in January
Long-run climate averages for San Francisco, CA in January, plus what the forecast models say for the days ahead.
In January, San Francisco averages 57°F by day and 47°F at night. It is the wettest month of the year here.
January in San Francisco averages a daytime high of 57°F and an overnight low of 47°F, which reads as cool for this part of the world. It is among the three coldest months of the year here. It is also the wettest month, so build rain into any plan. Across the whole year San Francisco sees roughly 33 inches of precipitation.
Climate averages tell you what to pack. They do not tell you what next Tuesday looks like - for that, see the live San Francisco forecast with every model compared and how much they currently agree.
San Francisco weather by month
what to expect in San Francisco through the yearHere is San Francisco's typical weather in each month: the average daytime high and overnight low in °F, how each month feels, and the wettest month marked. Use it to plan any trip to San Francisco by season.
Bottom line: over the last 30 days the European model has been the most accurate forecast for San Francisco, scoring 90/100 on our CheckWeather Score, ahead of the American at 77. See the full US accuracy scoreboard for exactly how every model is tested.
Common questions
How warm is San Francisco in January?
Is January a good time to visit San Francisco?
Does it rain a lot in San Francisco in January?
Climate averages from ERA5 reanalysis. Model accuracy re-scored over a rolling 30 days. Page updated .