What to Pack for San Francisco (When Summer Isn't Warm)

The mistake I made the first time

The first time I visited San Francisco, I packed for a California summer: shorts, T-shirts, one thin cardigan “just in case.” I stepped off the plane in late July into grey skies and a steady wind, and spent the first two days in a hoodie I bought near Fisherman’s Wharf because nothing else I’d brought was warm enough. That hoodie still lives in my closet as a reminder.

San Francisco’s summer fog — locals call it Karl the Fog — isn’t a rare event. It’s the defining feature of June, July and August here, and it catches almost everyone who’s never been before. Meanwhile September and October, which most visitors assume are “shoulder season” and pack lighter for, are usually the city’s warmest, sunniest stretch. If you only take one thing from this list, take this: pack for layers in every season, and don’t trust the calendar to tell you when to bring a jacket. I’ve gone deeper into why this happens in my piece on San Francisco’s summer fog and the month-by-month breakdown in San Francisco weather by month; if you’re still choosing dates, best time to visit San Francisco is worth a look too.

Why layering beats one “warm enough” coat

The trick with San Francisco isn’t finding your heaviest coat — it’s bringing pieces you can add and remove through the day, because the temperature genuinely swings that much between a sunny inland pocket and a foggy stretch of coastline just minutes away. I’ve stood in short sleeves in the Mission District at noon and put my jacket back on twenty minutes later at Ocean Beach. This is a real microclimate split, not exaggeration: the Mission and Noe Valley, sheltered by hills, run routinely warmer and sunnier than the fog-prone Sunset, Richmond, or the Golden Gate Bridge itself on the very same day.

My working system is three layers:

1. A base layer — a T-shirt or long-sleeve top you’re comfortable in all day.
2. A warm mid-layer — a fleece, sweater, or light down layer that you can stuff in a day bag.
3. A windproof outer layer — this is the one piece I never travel without. Fog in San Francisco comes with real wind, especially near the water, and a layer that blocks wind does more for comfort here than a layer that’s simply “warm.”

What to actually pack, month by month

Season	Typical daytime feel	What earns a spot in the bag
Summer (Jun-Aug)	Cool, grey, breezy; 60-66°F (15-19°C) in the fog belt, colder at the coast	Windproof packable jacket, fleece, long trousers, closed shoes, a scarf or light beanie for evenings
Fall (Sep-Oct)	The city’s real summer — warm, sunny, clearer skies	Lighter layers, a light jacket for evenings, sunglasses, still one warm layer for foggy mornings
Winter (Dec-Feb)	Mild but wet; rarely freezing	Waterproof or water-resistant jacket, warmer mid-layer, umbrella or rain shell
Spring (Mar-May)	Variable, transitional, some fog returning	Similar to summer: layers you can adjust, a windproof shell

Notice that summer, not winter, is where the warmest jacket in your bag tends to get the most use. That single line is the whole thesis of this packing list.

The rest of the bag

Beyond layers, a few things have earned their place on every trip since that first cold July:

• Comfortable, broken-in shoes with grip. San Francisco is genuinely hilly — steeper than most visitors expect — and a real day of sightseeing, whether you’re exploring Chinatown or walking down toward the Embarcadero, easily adds up to several miles. This is not a city for breaking in new shoes.
• A packable day bag. You’ll be adding and removing layers constantly, and you’ll want somewhere for a water bottle, a jacket, and whatever you pick up along the way.
• Sunglasses, even in a “grey” city. Fog clears without warning, especially inland or once you’re past the coast toward Napa Valley or Sonoma.
• A reusable water bottle. San Francisco’s hills make you thirstier than you’d expect, and refilling is easy almost everywhere.
• A light scarf or beanie for evenings. Even in warmer months, evenings by the water — around Alcatraz ferries or Sausalito — cool down fast once the sun drops.
• A phone charger and portable battery. Between transit apps, photos, and a full day out, I’ve drained a phone before dinner more than once.

If you’re deciding what to see rather than what to wear, my things to do in San Francisco hub and the practical basics in getting around San Francisco are good next stops, and if you’re travelling with kids, the layering logic above matters even more — see my San Francisco with kids guide for what that adds to the list.

What I leave at home

Just as important as what to bring is what not to bother with. I no longer pack:

• Heavy winter coats, even for winter trips — San Francisco rarely gets cold enough to need one, and a warm mid-layer plus a windproof shell covers it.
• Umbrellas as a first line of defense against fog — fog is damp, not rainy, and a hood usually does the job better than an umbrella in the wind.
• Formal shoes for daytime — outside of a specific dinner reservation, comfortable shoes win every time given the hills.
• A car-focused packing mindset for the city itself. I pack for walking and transit inside San Francisco and save the “road trip” gear — sunglasses, snacks, a phone mount — for day trips out toward Muir Woods or the coast, where a rental car genuinely earns its keep.

Making the most of a City Pass day

On days when I’m covering several major sights back to back — the kind of day layering matters most, since I’m outdoors from morning fog through afternoon sun — I’ve found a bundled pass useful for keeping logistics simple. The San Francisco Explorer Pass lets you pick attractions as you go, which suits a first visit where you’re still deciding how the weather will shape your day. For a longer stay, the San Francisco 9 Day CityPASS spreads the same idea across more time, which gives you room to reschedule an outdoor stop if the fog rolls in.

For the day trip that changes my packing list the most, it’s a coastal one. The Alcatraz, Muir Woods and Sausalito day tour combines a ferry crossing, redwood forest, and a waterfront town in one day — three different microclimates before dinner, which is exactly why the three-layer system above earns its keep. If you’re focusing only on the redwoods, the standalone tour of Muir Woods National Park is a simpler version of the same cool, damp environment, and it’s worth packing for accordingly: even on a warm downtown day, bring the fleece.

Packing for San Francisco: your questions answered

Do I really need a jacket in San Francisco in July?

Yes. July and August are the coolest, foggiest months in the city itself, with highs commonly in the 60-66°F (15-19°C) range and stronger wind and fog near the coast. A packable, windproof jacket is more essential in midsummer than in winter.

When is the warmest weather in San Francisco?

September and October, often called the city’s second summer, are usually the warmest and sunniest months as the marine layer retreats. If you want reliable T-shirt weather, aim for early autumn rather than July or August.

Is San Francisco colder than the rest of the Bay Area?

Often, yes. Fog-prone spots like Ocean Beach and the Sunset and Richmond districts run several degrees cooler than sheltered neighborhoods like the Mission and Noe Valley, and inland areas such as Napa or San Jose are frequently much warmer on the same day.

What shoes should I pack for San Francisco?

Comfortable, broken-in walking shoes with grip, since the city’s hills are steep and sidewalks can be uneven. Save anything delicate for dinner; most sightseeing days involve several miles of hilly walking.

Do I need rain gear for San Francisco?

A light, packable rain shell is worth having, especially outside the dry summer months, but San Francisco’s weather is more defined by wind and fog than by heavy rain. A windproof layer does double duty as light rain protection.

What should I pack for a day trip to Muir Woods or the coast?

Bring an extra layer beyond what you’d wear downtown. Redwood forests and coastal spots like Muir Woods and Ocean Beach are noticeably cooler and damper than sunnier inland neighborhoods, even in summer.

Can I get away with one jacket for the whole trip?

Usually yes, if you choose a windproof, packable layer rather than a heavy coat. Combined with a fleece or sweater underneath, one good jacket covers most San Francisco days across any season.