easeweather.com
Units
°C
°F
City and County of San Francisco
Forecast Today Tomorrow
more
California United States

Weather in City and County of San Francisco for September 2025

Your guide to City and County of San Francisco weather in September - trends and predictions
  • In general, the average temperature in City and County of San Francisco at the beginning of September is 21 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 18.1 °F by the end of September.

  • Precipitation in City and County of San Francisco during September is a rare event, with an average of fewer than 2 rainy days.

  • New! Chat with our AI weatherman - it’s amazing and free.
Average dry days
29
Dry days
Average rainy days
1
Rainy days
Average snowy days
0
Snow days
Average temperatures
20°/13°
Temperatures
Average wind speed
19 km/h
Avg max wind
Average humidity
82 %
Avg humidity

City and County of San Francisco in September average weather

Move between months or click on a day
Select a date

You can click on date

Access City and County of San Francisco weather forecasts with a simple click. Select any date for comprehensive insights on temperature, rainfall, and wind conditions.
Got it

Temperatures trend during September in City and County of San Francisco

See the weather trend as well as the moving average line

September weather day by day

Click on a date for more information
Date Weather Temperatures Rain UV More
Sept. 1 Overcast
Overcast
19° /13° 0 mm 4
Sept. 2 Mist
Mist
20° /14° 0 mm 5
Sept. 3 Mist
Mist
23° /13° 0 mm 6
Sept. 4 Mist
Mist
22° /14° 0 mm 6
Sept. 5 Mist
Mist
22° /14° 0 mm 6
Sept. 6 Mist
Mist
21° /13° 0 mm 6
Sept. 7 Mist
Mist
20° /12° 0 mm 6
Sept. 8 Fog
Fog
21° /12° 0 mm 6
Sept. 9 Fog
Fog
20° /12° 0 mm 5
Sept. 10 Fog
Fog
19° /12° 0 mm 5
Sept. 11 Fog
Fog
21° /12° 0 mm 6
Sept. 12 Mist
Mist
20° /13° 0 mm 5
Sept. 13 Fog
Fog
21° /13° 0 mm 6
Sept. 14 Fog
Fog
20° /13° 0 mm 5
Sept. 15 Mist
Mist
18° /13° 0 mm 5
Sept. 16 Mist
Mist
18° /13° 0.3 mm 4
Sept. 17 Overcast
Overcast
17° /13° 0 mm 4
Sept. 18 Mist
Mist
18° /12° 0 mm 5
Sept. 19 Mist
Mist
14° /12° 0 mm 4
Sept. 20 Mist
Mist
16° /12° 0 mm 4
Sept. 21 Mist
Mist
17° /11° 0 mm 4
Sept. 22 Fog
Fog
17° /11° 0 mm 4
Sept. 23 Overcast
Overcast
18° /11° 0 mm 4
Sept. 24 Mist
Mist
17° /11° 0 mm 5
Sept. 25 Mist
Mist
17° /12° 0 mm 4
Sept. 26 Patchy rain possible
Patchy rain possible
18° /13° 0.1 mm 5
Sept. 27 Mist
Mist
19° /12° 0 mm 5
Sept. 28 Mist
Mist
17° /11° 0 mm 4
Sept. 29 Partly cloudy
Partly cloudy
18° /12° 0 mm 5
Sept. 30 Light rain shower
Light rain shower
21° /13° 0.9 mm 5
Next
Important Notice
Our weather forecast for City and County of San Francisco in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the City and County of San Francisco forecast closer to your planned date for the most up-to-date weather information.

City and County of San Francisco in September - FAQ

What are the expected maximum and minimum temperatures in City and County of San Francisco during September?
Enjoy moderate daytime temperatures of up to 20° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in City and County of San Francisco during September?
Rainfall in City and County of San Francisco during September is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 1 days seeing any precipitation. Planning without the concern for rain is generally straightforward during this very dry period.
What are the typical wind conditions in City and County of San Francisco during September?
The average wind speed in City and County of San Francisco during September is 19 km/h, suggesting breezy to windy conditions, depending on your activities.

September rainfall patterns in City and County of San Francisco

Explore the daily rainfall trends and prepare for City and County of San Franciscos September weather 💧

UV exposure in City and County of San Francisco during September

Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Top locations in City and County of San Francisco
Select a location for an accurate weather forecast
More Locations

Quick links

Location coordinates Where is City and County of San Francisco?

Get accurate weather forecasts for City and County of San Francisco, located at latitude 37.775 and longitude -122.419. Stay updated with localized weather information tailored for City and County of San Francisco.

Found a mistake?
We appreciate your attention to details. Tell us here.