h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Don't rely on taxi cabs to get you around either. They are hard to find and harder to stop.

Pay attention to the section in your guidebook about the temperature. In the summer spotting a tourist is easy. They're the ones underdressed in shorts and t-Shirts, huddled together for warmth, shivering and with their knees literally knocking, as they wait for Muni or a cab to show up (Hint: Get a good map and walk - SF is "mostly harmless", avoid the Tenderloin district, north west of City Hall). Yes, it's in California, but it's in Northern California. Surrounded by cold water on three sides, the summer weather pattern in San Francisco means fog and breezes (wind actually) starting in the late afternoon until after dark. The reason you see San Francisco sweatshirts the world over is because that is what people end up having to buy when they visit because they didn't bring any warm clothes. In LA they buy T-Shirts.

No, you really don't want to live here. Rent and real estate is high enough as it is, and you're landing here won't help. That's why we're so irritable all the time.

I spent a week in SF this year with tempratures in the low 30s.
It was definitley shorts weather!

mark twain once said, "the coldest winter i ever spent was one summer in san francisco".

but san francisco has an astounding mix of microclimates. it so happens that the most tourist areas: fishermans' wharf, pier 39, the great highway, most of golden gate park... are in the arctic zone of the city. candlestick park has been abandoned for baseball because of the glacial evenings, but believe me, the solution was day games: the afternoons at hunter's point are generally beautiful. in neighborhoods like the mission or noe valley the weather is very pleasant year round. you can also find a curious landmark tourists rarely see at 20th and church in dolores park: the fire hydrant that saved the neighborhood in 1906; every year theer's a ceremony to repaint it gold.

I can vouch for this. As a tourist I was freezing cold in the bay and had my jacket zipped up but still got sunburnt.

Muni is terrible, BART doesn't go enough places, and cabs are scarce-- Get a bike and explore the city however you like.
The Tenderloin is rough for San Francisco, but it's not so bad that you shouldn't check it out.
With Bourbon & Branch, Divas, Sao Bien, a fascinating parade of crackheads, hookers, and miscreants of all types and degrees, what's not to love?