San Francisco turns the usual rules about travel seasons upside down. Its summer is cool and foggy, its warmest weather arrives in September and October, its winter is mild and green between rainstorms, and its busiest hotel weeks are set as much by the conventions at Moscone Center as by tourists. Airfares follow a more familiar pattern, with a summer peak and a winter low, but the hotel bill often moves in a different direction, and in a city where rooms are among the most expensive in the country, that matters as much as the fare. Add three airports within an hour of downtown, a morning fog that can slow arrivals at SFO, and a festival calendar that fills whole weekends, and the “best time” question has more than one right answer. This guide walks through the weather month by month, the fare seasons, the events and conventions that move prices, and how to handle the airports.
The short answer
For the best weather, come in September or October, when the fog retreats and the city has its warmest, clearest days of the year; hotel rates are high then, so book early. For the best balance of value and pleasant weather, April and May give you green hills, wildflowers, fewer crowds and moderate prices, and early November often keeps the fall sunshine at lower rates. The cheapest fares come in January and February, outside the week of the big healthcare investment conference in mid-January, and in the weeks between Thanksgiving and the Christmas rush. The most expensive stretches are June to August for airfares, when families and international visitors arrive, September and October for hotels, when conventions and good weather coincide, and the Christmas and New Year weeks. Whatever you choose, run a flexible-date search on our San Francisco flights page, and check hotel rates for the same dates before you commit, because a single convention can double the cost of a room.
San Francisco’s weather, season by season
San Francisco sits at the tip of a peninsula between the Pacific and the bay, and the cold ocean current offshore controls its climate. Winters are mild and wet, summers are cool and dry, frost and real heat are both rare, and the temperature range across the year is one of the narrowest of any large American city. The catch is the fog: in summer, the heat of California’s Central Valley draws cool, moist air from the ocean through the Golden Gate, and the western and northern parts of the city can spend whole weeks under a gray marine layer while the Mission and the East Bay bask in sun. The figures below are approximate seasonal patterns for downtown based on the long-term climate normals from NOAA’s National Weather Service office for the San Francisco Bay Area; check the current forecast before you pack, and remember that the Golden Gate Bridge and Ocean Beach are often several degrees cooler and much windier than downtown.
| Month | Typical daytime high | Typical overnight low | What it feels like | Fare pressure |
|---|---|---|---|---|
| January | around 14 °C (57 °F) | around 8 °C (46 °F) | The heart of the rainy season; clear, crisp days between storms | Low, except the healthcare conference week |
| February | around 16 °C (61 °F) | around 9 °C (48 °F) | Still wet, but the hills turn green and the first blossoms appear | Low; rises for Presidents’ Day weekend |
| March | around 17 °C (63 °F) | around 9 °C (48 °F) | Showers tapering off; windy, bright spells | Moderate; spring break and conventions |
| April | around 18 °C (64 °F) | around 10 °C (50 °F) | Spring proper, with wildflowers and the occasional late shower | Moderate |
| May | around 19 °C (66 °F) | around 11 °C (52 °F) | Mostly dry and pleasant; the first fog of the season arrives | Moderate; rises for Memorial Day |
| June | around 20 °C (68 °F) | around 12 °C (54 °F) | Dry, with fog most afternoons on the west side; Pride at month’s end | High |
| July | around 20 °C (68 °F) | around 13 °C (55 °F) | Peak fog season; cool and windy at the bridge and the beach | Peak |
| August | around 21 °C (70 °F) | around 13 °C (55 °F) | Similar, with fog easing late in the month | High |
| September | around 22 °C (72 °F) | around 13 °C (55 °F) | Often the warmest month; clear skies and occasional hot spells | Moderate for flights, high for hotels |
| October | around 22 °C (72 °F) | around 12 °C (54 °F) | Warm, clear and settled; the first rain usually late in the month | Moderate for flights, high for hotels |
| November | around 18 °C (64 °F) | around 10 °C (50 °F) | The rainy season begins; mild, often sunny early in the month | Low, except Thanksgiving |
| December | around 14 °C (57 °F) | around 8 °C (46 °F) | Cool and wet, with festive lights downtown | Low until mid-month, then peak |
Three things the table cannot show. First, the microclimates: on a July afternoon it can be 13 °C (55 °F) and misty at Ocean Beach, 20 °C (68 °F) and sunny in the Mission, and far hotter in Napa or the East Bay, all within an hour. Second, the wind: the afternoon sea breeze makes the waterfront, the bridge and the Alcatraz ferry feel colder than the numbers suggest in every season. Third, the storms: most of the city’s rain falls between November and March, often in a few heavy atmospheric-river storms that bring wind, flooding on the coast roads and airport delays, followed by days of brilliant clear weather. Summer, by contrast, is almost completely dry.
How San Francisco’s fare seasons work
Three calendars drive demand for San Francisco: leisure travel, which peaks in summer and at the holidays; the convention and business calendar, which fills Moscone Center and the downtown hotels for much of the year and is heaviest in the fall and late winter; and the tech industry, whose weekday business travel keeps flights from Seattle, Los Angeles, New York and Asia busy all year. The result is that airfares and hotel rates do not always move together. Summer is the peak for flights, as families and international visitors arrive, while September and October are often the peak for hotels, because the weather is at its best and the largest conferences are scheduled then. Winter is the value season for both, with one or two dramatic exceptions.
Peak season
June to August for airfares, plus roughly December 18 to January 3. Hotels are expensive all summer, and even more so during Pride weekend, Outside Lands and the Fourth of July. September and October are peak for hotels rather than flights, and a big convention week in the fall can push downtown room rates to their highest of the year. If you must travel in summer, book early, fly mid-week, and look at hotels near a BART station outside downtown.
Shoulder season
March to May, and November. Spring brings the greenest hills of the year, pleasant temperatures and moderate prices, though spring break and several large tech conferences can tighten hotels on particular weeks. November keeps some of October’s sunshine, with the rains usually starting in earnest later in the month, and rates fall steadily apart from Thanksgiving week.
Low season
January and February, and the first half of December. Fares are at their lowest, museums and Alcatraz are at their least crowded, and hotel rates drop sharply, except in the second week of January, when a major healthcare investment conference fills the Union Square hotels at some of the highest rates of the year, and on weekends with big conventions at Moscone. Build a weather buffer into connections, because winter storms can cause delays.
As elsewhere, mid-week departures and early or late flights usually price below Friday and Sunday afternoons on the same route, and a search across a whole month reveals cheaper pairs of dates close to your first choice. Our guide to the best times to book explains how to read those patterns.
San Francisco month by month
January
The heart of the rainy season, but between storms the days are clear and crisp and the views from Twin Peaks and the Golden Gate Bridge are the sharpest of the year. Fares are at their lowest after the New Year week. The exception is the second week of the month, when a large healthcare investment conference takes over Union Square and room rates soar; check hotel prices before you book flights for mid-January. Gray whales are passing the coast, and the headlands at Point Reyes are one of the best places to spot them.
February
Still wet, but the hills turn emerald green and the first magnolias and cherry blossoms bloom. The Chinese New Year Parade falls in February or early March, depending on the lunar calendar, and is one of the largest outside Asia; Chinatown hotels and restaurants fill for it. Presidents’ Day weekend lifts fares, but otherwise this is a strong value month.
March
The rain tapers off and bright, windy days become more common. Spring break brings families from mid-month, St. Patrick’s Day has a parade downtown, and large tech and gaming conferences can fill Moscone-area hotels on particular weeks. Prices rise to moderate levels.
April
One of the best months to visit: wildflowers on the headlands, green parks, comfortable temperatures and moderate prices. The Northern California Cherry Blossom Festival fills Japantown over two weekends, and the Giants’ baseball season opens at Oracle Park. A big security-industry conference at Moscone in the spring can push up downtown rates for a week; check before you book.
May
Mostly dry and pleasant, with the first fog arriving late in the month. Bay to Breakers, the costumed footrace across the city, is on a Sunday in May, and Carnaval fills the Mission on Memorial Day weekend, which lifts fares. The first half of May is one of the best value windows of the year.
June
Summer arrives and so does the fog, rolling in most afternoons over the west side while the eastern neighborhoods stay sunny. Schools finish, fares rise, and San Francisco Pride, on the last weekend of the month, is one of the largest celebrations in the world and fills every hotel in the city. Early June is the value play.
July
Peak season for flights, and the height of the fog. Visitors who arrive in shorts are regularly seen buying sweatshirts at Fisherman’s Wharf; bring a jacket. The Fourth of July fireworks over the bay are sometimes hidden by the fog. The sights are at their busiest, so book Alcatraz well ahead, and ride the cable cars early.
August
Similar to July, with the fog easing toward the end of the month. Outside Lands, the big music festival in Golden Gate Park, fills the city’s hotels for its weekend, usually in early or mid August. The last two weeks, once schools on the East Coast go back, can be slightly softer on fares.
September
The month San Franciscans would send you to: the fog retreats, the days are the warmest of the year, and the evenings are mild enough to eat outside. The summer crowds thin after Labor Day, so fares ease, but hotels stay expensive because this is prime convention season. The Folsom Street Fair is on the last Sunday of the month, and the wine-country harvest is under way to the north.
October
Warm, clear and settled, often with the finest weather of the year. Fleet Week brings the Navy’s Blue Angels over the bay in early October, and Hardly Strictly Bluegrass, a free music festival in Golden Gate Park, usually falls on the same or a nearby weekend. Salesforce’s giant Dreamforce conference, held in the fall, can fill downtown hotels for a week. Fares are moderate, rooms are not, and the first winter rain usually arrives late in the month.
November
The rainy season begins, but early November often keeps the fall sunshine, and fares and hotel rates fall steadily. Thanksgiving week is the exception. The Dungeness crab season normally opens around now, though openings have been delayed in some recent years, and the holiday lights and the Union Square tree appear at the end of the month.
December
Two months in one. The first half is cool, often wet and good value, with festive windows, the ice rink in Union Square and holiday events across the city. From about December 18, fares and hotel rates jump for Christmas and New Year, when San Francisco is a popular stop on California holiday trips and the New Year’s Eve fireworks over the Embarcadero draw big crowds.
Events that move San Francisco flight and hotel prices
Cross-check these against your dates before you book. Exact dates shift each year; San Francisco Travel keeps the current calendar.
- The healthcare investment conference (second week of January): one of the most expensive hotel weeks of the year downtown.
- Chinese New Year Parade (February or early March).
- Large conventions at Moscone Center, especially in the spring and fall; if downtown rates look strangely high mid-week, that is usually why.
- Bay to Breakers (a Sunday in May) and Carnaval (Memorial Day weekend).
- San Francisco Pride (last weekend of June).
- Outside Lands (a weekend in August).
- Dreamforce (in the fall), Fleet Week and Hardly Strictly Bluegrass (early October).
- Thanksgiving and Christmas to New Year.
- Giants and Warriors home games and stadium concerts. Our San Francisco events page shows what is on sale for your dates.
Getting in from the airport
San Francisco is served by three major airports, and choosing between them can save money. San Francisco International (SFO), about 21 km (13 miles) south of downtown, is the main gateway, a major hub for United with nonstop flights across North America, Asia, Europe and Australia. BART trains run from the station at the International Terminal to downtown in about 30 minutes, and the free AirTrain connects every terminal with the BART station and the rental car center; taxis and ride-hail take 25 to 45 minutes depending on traffic. Oakland International (OAK), across the bay, is often cheaper on domestic routes, especially with Southwest, and a BART connector links it to the main network, making downtown San Francisco about 30 to 40 minutes away. San José (SJC), about an hour south, suits visitors heading to Silicon Valley. One SFO-specific quirk: the airport’s closely spaced parallel runways mean that low cloud and fog, most common on summer mornings, reduce the number of arrivals it can handle, so delays build up on foggy days. If you have a tight connection or an evening event, allow extra time; our guide to how early to arrive covers the departure side. Our SFO airport guide covers the layout, and our San Francisco car-versus-transit guide explains why most visitors do not need a car in the city.
Timing tricks that work for San Francisco
- Price the hotel first. A cheap fare into a convention week is not cheap once the room is added. Run a San Francisco hotel search for your dates before you commit, and compare downtown with Fisherman’s Wharf, which is less affected by business travel.
- Search the whole month. Pride, Outside Lands and the big conferences create sharp edges in the calendar; a calendar search on TicketScanner shows them instantly.
- Compare all three airports. Oakland is often cheaper for domestic flights and is on BART; San José can be cheaper for Silicon Valley trips.
- Fly mid-week. Tech business travel makes Monday morning and Thursday and Friday evening flights the busiest on most routes.
- Allow for fog and storms. Summer morning fog and winter storms both slow SFO arrivals; avoid the tightest connections.
- Combine it with Los Angeles. An open-jaw ticket, flying into San Francisco and out of Los Angeles, often costs little more than a return; drive between them on our San Francisco to Los Angeles route, and see our guide to the best time to fly to Los Angeles for the other end.
- Flying out of San Francisco instead? The same seasonality applies in reverse; see cheap flights from San Francisco.
What to pack, by season
Winter (December to February): a waterproof jacket, an umbrella, shoes that cope with wet, steep sidewalks, and a warm layer for the evenings. Spring (March to May): layers and a windproof jacket, and sunglasses for the bright days. Summer (June to August): this is the season visitors get wrong. Pack a fleece or sweater and a windproof jacket, long pants and closed shoes, because the fog and wind make the waterfront, the bridge and the Alcatraz ferry genuinely cold, even when the Mission is warm; add sun protection for the afternoons when it clears. Fall (September to October): lighter clothes for the warm days, a layer for the evenings, and sun protection. In every season, comfortable walking shoes are essential, because the hills are real.
The best time to fly to San Francisco for…
Warm weather
September and October, when the fog retreats and the city has its warmest days; book the hotel early.
Sightseeing with fewer crowds
April, May and early November, when the weather is pleasant, Alcatraz tickets are easier to get and hotel rates are moderate.
The lowest fares
January and February outside the mid-January conference week and Presidents’ Day, and the first half of December.
Wine country
September and October for the harvest and the warmest weather, or spring for green vineyards and quieter tasting rooms.
Families
Summer, when schools are out, with warm layers for the fog; or the spring break weeks, which are often sunnier.
International visitors
Visitors from Visa Waiver Program countries need an approved ESTA before boarding; most others need a visa. The State Department’s travel site explains what applies to you, and the TSA lists what you can carry through security.
Frequently asked questions
What is the cheapest month to fly to San Francisco?
January and February are consistently the lowest for airfares, followed by early December and early November. Watch the mid-January conference week, when hotel rates soar.
What is the best month to visit San Francisco for weather?
September or October, the warmest and clearest months. April and May are a close second, with green hills and fewer crowds.
Why is San Francisco so cold in summer?
Heat in California’s interior draws cool, moist air from the Pacific through the Golden Gate, creating the fog that blankets the western and northern parts of the city on most summer afternoons.
Should I fly into SFO or Oakland?
Compare both. SFO has more flights and international service; Oakland is often cheaper for domestic trips and is on BART, about 30 to 40 minutes from downtown San Francisco.
When does it rain in San Francisco?
Mostly between November and March, often in a handful of big storms. From June to September, rain is rare.
How far ahead should I book?
Earlier for summer, Pride weekend, the fall convention season and the holidays, when prices tend only to rise. For January to early March, finding the right dates matters more than booking far ahead.
Are flights into SFO often delayed?
On foggy summer mornings and during winter storms, arrival delays are common because the airport has to space landings further apart. Allow a buffer for connections.
Ready to pick your dates? Compare fares across the whole month on our San Francisco flights page, then find a room with our San Francisco hotel search. For what to do when you land, start with our first-timer’s guide to San Francisco.
Keep planning with TicketScanner
- Cheap flights to San Francisco — compare fares across the whole month
- San Francisco hotels — check convention weeks before you book
- San Francisco car rentals — for wine country and the coast
- Events in San Francisco — Giants, Warriors, concerts and shows on sale
- Things to do in San Francisco: a first-timer's guide
- San Francisco: rent a car or use transit?
- San Francisco International (SFO) airport guide
- Where to stay: Fisherman's Wharf
- Best time to fly to Los Angeles
- Best times to book flights and hotels
