Weather & Climate in San Francisco, CA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
San Francisco enjoys a temperate climate with an average annual temperature of 58°F (14°C). Winters average 52°F in January while summers reach 60°F in July / relatively mild seasonal variation. Annual precipitation totals 36.2 inches. Air quality is rated Good with a median AQI of 33. 76% of days have good air quality.
Temperature
52°F Jan (11°C)
60°F Jul (16°C)
| Annual Average | 57.7°F |
| 7% above US avg | |
| January Average | 52°F (11°C) |
| July Average | 60°F (16°C) |
Geography
| Area | 231.9 sq mi (600.6 km²) |
| Population Density | 17,912/sq mi |
| Coordinates | 37.7272°N, 123.0322°W |
| Timezone | America/Los_Angeles |
| County | San Francisco County County |
| Nearest Airport | San Francisco International (SFO) 37 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 33.0 |
| Rating | Good |
| Good Days % | 76.0% |
| Unhealthy Days | 0 |
Natural Hazard Risk
| Overall Risk | Very High |
| Risk Score | 99.5 / 100 |
| Social Vulnerability | 48.1 / 100 |
| Community Resilience | 99.7 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Earthquake | Very High |
| Wildfire | Very Low |
| Flood | Relatively High |
| Hail | Very Low |
| Strong Wind | Very Low |
| Heat Wave | Relatively Moderate |
| Winter Weather | Very Low |
| Lightning | Relatively Low |
| Drought | Relatively Moderate |
| Cold Wave | No Rating |
| Landslide | Relatively High |
| Coastal Flood | Relatively Moderate |
| Tsunami | Relatively Moderate |
| Volcano | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
3,991 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M6.0.
| Aug 24, 2014 | The 2014 South Napa, California Earthquake | M6.0 | 83 km | 11 km |
| Apr 18, 1990 | 4 km E of Interlaken, California | M5.1 | 147 km | 7 km |
| Sep 3, 2000 | 5 km WSW of Yountville, California | M4.9 | 91 km | 9 km |
| Sep 4, 1995 | 13 km SW of Middletown, California | M4.8 | 109 km | 7 km |
| May 12, 2006 | 7 km W of Cobb, California | M4.7 | 123 km | 4 km |
| May 21, 1996 | 8 km ESE of East Foothills, California | M4.7 | 123 km | 8 km |
| Aug 11, 1993 | 14 km ESE of Alum Rock, California | M4.7 | 128 km | 9 km |
| Jan 2, 2025 | 4 km NW of Cobb, CA | M4.7 | 127 km | 1 km |
| Aug 18, 1999 | 0 km S of Bolinas, California | M4.6 | 36 km | 8 km |
| Mar 24, 1991 | 1 km NNE of Interlaken, California | M4.6 | 143 km | 15 km |
| Jan 11, 2000 | 6 km N of Geyserville, California | M4.6 | 116 km | 6 km |
| Feb 18, 2004 | 4 km WNW of Cobb, California | M4.6 | 126 km | 3 km |
| Jan 12, 2014 | 8 km W of Cobb, California | M4.5 | 122 km | 2 km |
| Aug 3, 2006 | 5 km W of Glen Ellen, California | M4.5 | 81 km | 9 km |
| Jun 8, 2024 | 7 km NW of The Geysers, CA | M4.5 | 122 km | 4 km |
| Sep 19, 1992 | 7 km NW of Cobb, California | M4.5 | 128 km | 3 km |
| Apr 24, 2007 | 7 km WSW of Cobb, California | M4.5 | 121 km | 2 km |
| Jun 3, 2023 | 2km NW of The Geysers, CA | M4.5 | 121 km | 4 km |
| Mar 14, 2013 | 5 km W of Cobb, California | M4.4 | 123 km | 1 km |
| Mar 1, 2011 | 8 km W of Cobb, California | M4.4 | 122 km | 2 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
26 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF2. Total: 2 injuries.
| Date | Rating | Distance | Path | Fatalities |
| May 5, 1998 | EF2 | 97 km | 0.6 mi | 0 |
| Jun 1, 1958 | EF2 | 62 km | 15.0 mi | 0 |
| Jan 11, 1951 | EF2 | 90 km | 5.7 mi | 0 |
| Mar 18, 2011 | EF1 | 86 km | 0.1 mi | 0 |
| Mar 20, 2005 | EF1 | 55 km | 3.0 mi | 0 |
| Jan 27, 2005 | EF1 | 100 km | 0.5 mi | 0 |
| Dec 5, 1998 | EF1 | 86 km | 1.5 mi | 0 |
| May 5, 1998 | EF1 | 89 km | 0.3 mi | 0 |
| Dec 23, 1996 | EF1 | 59 km | 6.0 mi | 0 |
| Feb 22, 1996 | EF1 | 95 km | 1.0 mi | 0 |
| Dec 2, 1992 | EF1 | 93 km | 3.0 mi | 0 |
| Dec 2, 1992 | EF1 | 76 km | 7.5 mi | 0 |
| Dec 2, 1992 | EF1 | 77 km | 1.0 mi | 0 |
| Feb 27, 1983 | EF1 | 86 km | 0.8 mi | 0 |
| Nov 10, 1964 | EF1 | 92 km | 1.0 mi | 0 |
| Feb 17, 1959 | EF1 | 90 km | 0.5 mi | 0 |
| Apr 1, 1958 | EF1 | 61 km | 0.2 mi | 0 |
| Apr 7, 2011 | EF0 | 98 km | 0.1 mi | 0 |
| Dec 29, 2004 | EF0 | 86 km | 0.2 mi | 0 |
| Dec 5, 1998 | EF0 | 64 km | 1.5 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
5 tsunamis recorded within 500 km. Highest wave on record: 4.5 m (15 ft).
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1868 | N. CALIFORNIA | Eruption + Earthquake | 4.5 m | 30 | 82 km |
| 1989 | N. CALIFORNIA | Earthquake | 1.0 m | 62 | 127 km |
| 1856 | N. CALIFORNIA | Eruption + Earthquake | 0.6 m | - | 69 km |
| 1906 | N. CALIFORNIA | Eruption + Earthquake | 0.1 m | - | 47 km |
| 1865 | N. CALIFORNIA | Eruption + Earthquake | - | - | 116 km |
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
1 volcano within 200 km. Closest: Clear Lake (140 km).
| Name | Type | Elevation | Last Eruption | Distance |
| Clear Lake | Volcanic field | 1,439 m (4,721 ft) | Unknown | 140 km |
Source: Smithsonian Institution Global Volcanism Program (GVP).
Wildfire History
12 wildfires (100+ acres) recorded within 100 km. Largest: CZU AUG LIGHTNING (85,894 acres, 2020).
| Year | Name | Acres Burned | Distance |
| 2020 | CZU AUG LIGHTNING | 85,894 | 97 km |
| 2017 | NUNS | 56,883 | 83 km |
| 2020 | WALLBRIDGE | 55,194 | 99 km |
| 2017 | ATLAS | 51,664 | 99 km |
| 2017 | TUBBS | 36,981 | 98 km |
| 1995 | VISION | 11,931 | 38 km |
| 2020 | WOODWARD | 4,952 | 38 km |
| 2008 | WILD | 4,100 | 99 km |
| 2020 | MEYERS | 2,460 | 88 km |
| 1996 | PGE 8 | 2,323 | 86 km |
| 1991 | TUNNEL | 1,838 | 72 km |
| 2017 | THIRTY SEVEN | 1,773 | 68 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 52°F (11°C) | 6.6 in | Coldest |
| February | 54°F (12°C) | 6.8 in | |
| March | 56°F (13°C) | 4.6 in | |
| April | 56°F (14°C) | 2.3 in | |
| May | 58°F (14°C) | 1.4 in | |
| June | 60°F (15°C) | 0.5 in | |
| July | 60°F (16°C) | 0.0 in | Driest |
| August | 62°F (17°C) | 0.1 in | |
| September | 63°F (17°C) | 0.2 in | Warmest |
| October | 62°F (17°C) | 1.7 in | |
| November | 57°F (14°C) | 4.2 in | |
| December | 53°F (11°C) | 7.9 in | Wettest |
San Francisco has a seasonal temperature swing of 11°F / from 52°F in January to 63°F in September. Total annual precipitation is 36.2 inches, with December being the wettest month (7.9") and July the driest (0.0").