San Francisco is always and forever associated with its fog. The "marine layer" as the weather people call it. The well known views of SF are from the Marin Headlands and usually feature fog flowing over the the Golden Gate bridge. This picture was taken on a day with pretty heavy fog, in the early morning.

The fog layer has many personalities. Sometimes, it's a high layer that makes the day dreary. Sometimes, it's only around in the morning before burning off, and you have to get up early to see it flowing over Nob Hill and Russian Hill.

And most evenings, if the day has been clear, the fog rolls back in. This is the view of Coit Tower from where I live.

Sometimes, there are spectacular sunsets