average weather san francisco, ca
50 Â°F min. or less (10 Â°C) Every day in San Francisco normally warms to over 40 Â°F (4 Â°C), and most reach 50 Â°F (10 Â°C). The city averages just 2 days a year when the thermometer reaches into the 90s Â°F (over 32 Â°C). The temperature normally doesn't climb above 100 Â°F (38 Â°C), even on the hottest days.