When it comes to the weather, San Francisco is a tricky place to visit. Weather is unpredictable all year, with some years having warm, sunny Januarys and cold, rainy Augusts and other years having the opposite.
San Francisco’s weather does not follow the California stereotype of being warm and sunny all year, and in fact is much colder that most people think.
In general, the best time of year to visit San Francisco is in September and October, when temperatures are in the 70’s F / 20’s C and days are sunny.
Summers in San Francisco tend to have a mix of warm sunny days and cool, foggy or rainy ones, so it’s always hard to know what you’ll get when you visit San Francisco in the summer.
Spring in San Francisco experiences a decent amount of rain, with temperatures in the 50’s and 60’s F / 15 – 20 C. Winters are a bit colder, but with similar rainy spells.
The general rule about the best time to visit San Francisco is that there isn’t one. Whatever time of year you visit, make sure to bring a few sweaters and a jacket, as well as an umbrella.