Looking at the weather forecast for San Francisco for 3 days or the weather forecast for San Francisco for 14 days, you are likely to take with you only light clothes. And you will regret it.
The weather in Frisco is quite illogical. It differs significantly from the rest of the cities of California. Summer here is windy and not as hot as you might assume - on average +20-23°C. Winter is not cold, but rainy, the average temperature in December-January is +13°C, in February - +15°C.
By the way, when looking at weather forecasters' forecasts, keep in mind that in America, temperatures are measured in Fahrenheit, not Celsius. To make it easier for you to see the weather in San Francisco for a week, day or month, use a metric converter.
Although no San Francisco weather forecast will tell you about the city's peculiarities, such as the need to carry warm clothes with you at all times (even in the summer!). Why?
The thing is, the weather in San Francisco changes not only on a monthly, daily, and hourly basis, but also on a neighborhood-by-district basis. After walking down a couple of streets in a T-shirt and shorts, you can suddenly find yourself in a neighborhood where your nose turns red and you can't get a tooth on a tooth from the cold, so you have to rush to a store to get a sweater or jacket.
If you want a real summer, come to Bay City in October, not June or July. But no one but locals or fellow travelers can tell you that, either. Weather forecast in San Francisco for 5 days or a month is so accurate. At least you can't make a mistake with the next 24 hours.
