San Francisco Weather in October
San Francisco, California basks in warm, sunny weather during October. This is the city's second hottest month of the year.
This page gives detailed information on the typical October temperature, precipitation, sun, humidity, wind and storms for San Francisco. The temperature, rainfall, sunshine and wind speed numbers here are historical averages based on climate data gathered in downtown San Francisco near the corner of Buchanan and Hermann Streets. The other measurements are averages at San Francisco International Airport, located south of the city center.
|70 °F||October average high||21 °C|
|54 °F||October average low||12 °C|
|14 days||70 °F max. or more (21 °C)|
|3 days||50 °F min. or less (10 °C)|
Nearly every October day warms to over 60 degrees Fahrenheit (16 degrees Celsius) in San Francisco. The city averages 5 days this month when the thermometer reaches into the 80s °F (over 27 °C). In some years it gets as hot as 90 °F (32 °C) during October.
Usually the thermometer dips below 60 °F (16 °C) every night this month. But October does not normally get as cold as 40 °F (4 °C).
|0.9 in||total precipitation||24 mm|
|4 days||of rain|
Half the time, San Francisco receives 0.2 to 1.5 inches (6 to 37 mm) of rainfall in October. One in four years has drier weather, while another one in four is wetter.
|16 days||clear skies|
The sun's rays reach the ground in San Francisco during 70 percent of daylight hours on average in October, for a total of 243 hours in the month. Typically on 16 days this month the sky is mainly clear, with at most 30 percent cloud cover.
Sunlight in October at San Francisco lasts for 11 hours and 11 minutes a day on average. The longest day of the month is the 1st with 11 hours and 47 minutes of daylight. By the end of the month, the days have shortened to 10:37 from sunrise to sunset. These durations can vary by a minute or two from year to year.
|72 %||October average humidity|
The relative humidity in San Francisco during October usually peaks at 82 percent in the morning then drops to 55 percent by early afternoon.
|Local Time||1 am||4 am||7 am||10 am||1 pm||4 pm||7 pm||10 pm|
|7.6 mph||October wind speed average||12.2 kph|
October is less windy than most other months in San Francisco.
|1 day||rainfall of 0.5 inches (13 mm) or more|
|0 days||with thunderstorms in October|
San Francisco has a heavy October rainstorm in many, but not all years.
About once in five years, an October thunderstorm passes through San Francisco.
The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.