Should be clear tomorrow, stellar view at the top of Twin Peaks, don't go too early or it will be all fogged in.
Exploratorium is pretty awesome too, if you have kids with you especially, near Palace of Fine Arts down in the Marina. Looks like they may be moving though.
Exploratorium: the museum of science, art and human perception
Yellow Submarine for sandwiches, 5th and Irving, block away from an N-Judah streetcar stop, get one, go have lunch in GG Park. I am partial to the Pacific Cafe on Geary for dinner