San Francisco

Here's the thing about San Francisco that catches most people off guard: it's cold. The annual average high is only 17.6°C (64°F), which means even summer doesn't feel like summer if you're coming from anywhere else. That said, May through August is genuinely when the city shows up best — you'll get the most reliable dry spells and actual warmth, though "warmth" is relative when you're talking about a place that basically never breaks 27°C (80°F) even at its peak.

May kicks things off with that perfect shoulder-season sweet spot: highs around 21°C (70°F), the fog hasn't fully retreated but it's breaking up by afternoon, and the wildflowers are still going in Marin County. June is when tourists arrive en masse because the fog finally burns off consistently — you get those crystalline blue-sky days that make the Golden Gate Bridge photos actually worth taking. July and August are the warmest months (highs around 23–24°C / 73–75°F), the driest, and when street fairs and outdoor concerts dominate the calendar. The trade-off? Crowds everywhere, hotel prices spike, and you'll see that famous Karl the Fog meme come to life on cooler afternoons.

Winter (November through March) is when most visitors ghost the city, and honestly, that's a shame — but also understandable. You're looking at gray skies, persistent fog that rolls in by mid-morning, and that damp chill that makes 13°C (55°F) feel colder than it should. The city gets about 575 mm of rain annually, and most of it lands between November and April. Businesses stay open, but the vibe flattens. April and September are genuinely underrated months if you can handle occasional drizzle and 16–19°C (61–66°F) temps — fewer crowds, prices drop, and you still get pockets of sunshine.

Looking at 2026 specifically: San Francisco's climate isn't trending dramatically different from the historical average, but like everywhere, the fog patterns are shifting slightly later into summer and clearing a bit sooner some years. The core truth remains — this is a city that runs on maritime influence, which means your 2026 visit will likely follow the same script as every other year: pack layers, embrace the fog as part of the experience, and hit the city May through August if you want guaranteed warmth and blue skies.