San Francisco (SF) weather in October
October in San Francisco: nice, dry, with clean air — an excellent time to visit.
Updated September 2026 · climate normals from ERA5 reanalysis
#5 of 12 months in San Francisco · #154 of 1413 destinations to visit in October · comfort 90/100 (tier S)
- Days
- 21°C
- Nights
- 13°C
- Wet days
- 2
- Sun
- 9.5 h
- Humidity
- 71%
- Daylight
- 11 h

What October is like in San Francisco
The other warm clear month, and the best of the two, with the last of the outdoor season before the rain.
peak
confidence: high
Traveller notes on San Francisco in October
San Francisco's forum rates October as one of the nicest months of the year — an average high near 70°F with comparatively little fog or rain compared to summer. Regulars flag the city's microclimates as the real variable: neighborhoods near the bay or ocean stay cooler and windier while inland pockets like the Mission run noticeably sunnier, so days can swing from the 50s to 80s°F depending on where in the city you are.
Other months in San Francisco
San Francisco-forum threads on September weather are consistently upbeat, calling it one of the better months of the year here, mild days in the 70s once morning fog burns off by late morning most days. Posters describe the fog itself as a near-daily fixture along the waterfront and bridge in the early hours, thinning out by 11am before a clear, mild afternoon takes over. The summer fog pattern that keeps downtown cool in June and July has largely broken by this point, and the heavier weather systems that arrive later in autumn haven't started yet, leaving September genuinely dependable. Regulars still recommend layers over shorts, since spots right on the water - the Wharf, Ocean Beach, the bridge itself - run noticeably cooler than the rest of the city regardless of the season. The record: 21.6C days feeling like 21C, 14C nights, just 2.5mm across 0.5 days, a 16.8C sea, 75 percent humidity and 11.2 hours of sun.
San Francisco-forum threads on July fog are consistent: this is the deepest fog season of the year, especially near the water, and the pattern is for it to clear downtown and most neighborhoods by late morning before rolling back in during late afternoon - though how much any given day burns off depends entirely on which part of the city you're in. Posters are firm that this isn't something to plan around avoiding; it's part of what the city is in summer, and it doesn't stop sightseeing. The advice is uniform: long pants and a jacket, dressed in layers. The record explains why the fog wins: 19.1C days, 12.6C nights, essentially no precipitation across the whole month, and a 14.8C sea - San Francisco's summer is dry, cool and grey rather than the postcard version most visitors expect.
Forum posters describe March as one of the most changeable months in San Francisco - it could be warm, cold or rainy, with morning lows typically in the mid-to-upper 40sF and afternoon highs in the low-to-mid 60sF. Posters are consistent that any lingering rain is generally the tail end of the rainy season, with the major winter storms usually done by late March, though posters note it doesn't necessarily turn warm either - even in a typical year, only 2-3 days in the back half of the month might bring genuinely warm weather. Posters consistently emphasize real block-to-block variability, with temperatures feeling 5-10 degrees different between a sunny and shady side of the same street, and a 70F day cooling down to 50F by night. Posters generally recommend serious layers plus a lightweight raincoat regardless of the specific forecast.
San Francisco forum regulars describe February as storm-and-clear, not steady rain: winter here comes in “discrete storms lasting a few days followed by clear weather,” roughly 40% rainy at most, with shorter storms than January. Expect “lows in the 40s at night” and “50s during the day” — layers from polar fleece to a light winter jacket, plus an umbrella and windbreaker for when a storm rolls through. The upside regulars keep repeating: smaller crowds and very low rates. One practical warning for anyone adding Big Sur — Pacific storms this month can close stretches of Highway 1 to rock slides. Our record: 15.3°C days, 6.4°C nights, 5.8 rain days and an 11.2°C sea — cool and mostly dry, with real storm risk stacked into a handful of days rather than spread evenly.
Year-round notes are on San Francisco's overview. Add your own note from San Francisco's card on the map.
San Francisco climate normals — October
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in San Francisco in October
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsthe editor's peak month, Hardly Strictly Bluegrass, Fleet Week
Peak crowdsBusyShoulder seasonQuiet
Best months for San Francisco's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherSan Francisco's weather peaks July–September.
Best weatherFair weatherToughest weather
What's on in San Francisco in October
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Festival
Hardly Strictly Bluegrass
2–4 OctMusic festivalCrowdedFree and ticketless in Golden Gate Park over the first weekend of October, in the city's warmest, clearest fortnight of the year. Source ↗
- Festival
Fleet Week
4–12 OctMajor festivalCrowdedShips in the bay and the Blue Angels over it for a week in early October; the noise is unavoidable across the northern half of the city and the waterfront is solid. Source ↗
Nearby, and something's on
Within 300 km of San Francisco — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is San Francisco?
San Francisco in October — FAQ
- Is October a good time to visit San Francisco?
- October in San Francisco: nice, dry, with clean air — an excellent time to visit. It ranks #5 of 12 months for San Francisco on SeasonMap's comfort score (90/100).
- What is the weather like in San Francisco in October?
- In October, San Francisco averages a daily high of 21.4°C and a low of 13°C, with about 28.8 mm of rain over roughly 2 rainy days.
- What is the air quality in San Francisco in October?
- San Francisco has a mean US Air Quality Index of about 40 in October.
Within 300 km: Santa Cruz, California's Monarch butterflies around 15 Oct – 15 Feb, and Monterey's Monarchs at Pacific Grove around 20 Oct – 28 Feb.