San Francisco weather in September 2025

Expect 22°C daytime maximum temperatures in the shade with on average 9 hours of sunshine per day in San Francisco in September. Check more long-term weather averages for San Francisco in September before you book your next holiday to California in 2025/2026.

  • 22°C maximum daytime temperature in September in San Francisco22
    22°C max day temperature
  • 9 hours of sunshine per day
  • 2 days with some rainfall in September in San Francisco2
    2 days with some rainfall
  • 13°C minimum night-time temperature in September in San Francisco13
    13°C min night temperature
  • 12 hours of daylight per day in September in San Francisco12
    12 hours of daylight per day
  • No heat & humidity in September in San Francisco0
    No heat & humidity
  • 7 mm monthly rainfall in September in San Francisco7
    7 mm of monthly rainfall
  • UV (maximum) index 7 (High) in September in San Francisco7
    7 (High) UV index
  • 14°C sea temperature in September in San Francisco14
    14°C sea temperature

More about San Francisco

San Francisco by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for California

  • Book online with TUI & save up to 7% on holidays
  • FREE child places available for select holidays
  • Pay £0 deposits with direct debit & spread the cost

TUITUI deal finder

The September weather guide for California (San Francisco) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm)  |  Imperial (°F / inches)

Back to top

More about San Francisco

How hot is it in San Francisco in September?

Daytime temperatures usually reach 22°C in San Francisco in September, falling to 13°C at night.

How sunny is it in San Francisco in September?

There are normally 9 hours of bright sunshine each day in San Francisco in September - that's 73% of daylight hours.

How warm is the sea around San Francisco in September?

The average sea temperature around San Francisco in September is 14°C.

Does it ever rain in San Francisco in September?

There are usually 2 days with some rain in San Francisco in September and the average monthly rainfall is 7mm.

San Francisco September sunrise & sunset times

Browse the sunrise and sunset times for San Francisco in September 2025. Select a month to view San Francisco sunrise and sunset times for the next 12 months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Monday, 1st September 2025 05:40 18:38
Monday, 15th September 2025 05:52 18:17
Tuesday, 30th September 2025 06:05 17:54

Related posts

Popular travel offers

Explore holidays in the sun for less

More holidays

Airport parking

More parking

Airport lounges

More lounges

Top ^