San Francisco

San Francisco is known as the air-conditioned city because of its two-season climate: a cool, pleasant summer and a mild spring. Flowers bloom throughout the year, and warm clothing is needed every month. Sea fogs and associated low stratus clouds are a striking characteristic of the city climate. On average, though, the sun shines during 66% of the daylight hours. There are wide contrasts in climate within short distances of the bay. Nearby communities of Marin County, to the north across the Golden Gate and sheltered from the prevailing winds by high peaks and ridges of the Coast Ranges, enjoy warmer and sunnier weather than the city.

The City, as it is called in northern California, packs its inhabitants into a compact area at the tip of a long peninsula making it the most densely populated city in North America after New York City.