Click on a day for an hourly weather forecast
The temperatures in San Francisco in September are comfortable with low of 14°C and and high up to 25°C.
There is little to no rain in San Francisco during September, so it’s a lot easier to explore the city. Just remember to dress in warm layers, as it can still get pretty chilly.
Our weather forecast can give you a great sense of what weather to expect in San Francisco in September 2025.
If you’re planning to visit San Francisco in the near future, we highly recommend that you review the 14 day weather forecast for San Francisco before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 15° / 7° | 4 | 27 | 0 | 63 mm | Good | San Francisco in January |
| February | 16° / 7° | 4 | 24 | 0 | 61 mm | Good | San Francisco in February |
| March | 17° / 8° | 5 | 26 | 0 | 62 mm | Good | San Francisco in March |
| April | 18° / 9° | 2 | 28 | 0 | 22 mm | Good | San Francisco in April |
| May | 20° / 10° | 1 | 30 | 0 | 13 mm | Good | San Francisco in May |
| June | 23° / 12° | 0 | 30 | 0 | 6 mm | Perfect | San Francisco in June |
| July | 25° / 14° | 0 | 31 | 0 | 3 mm | Perfect | San Francisco in July |
| August | 25° / 14° | 0 | 31 | 0 | 3 mm | Perfect | San Francisco in August |
| September | 25° / 14° | 0 | 30 | 0 | 4 mm | Perfect | San Francisco in September |
| October | 23° / 13° | 1 | 30 | 0 | 26 mm | Perfect | San Francisco in October |
| November | 18° / 10° | 3 | 27 | 0 | 37 mm | Good | San Francisco in November |
| December | 14° / 8° | 4 | 27 | 0 | 55 mm | Good | San Francisco in December |