Today I flew out of San Francisco in the late afternoon. I had an 4pm flight to LAX followed by a 715pm flight to San Antonio, arriving at 1159pm--actually 1205am, but very close.
Yesterday I rode through one of the temperature shifts that happen between San Francisco and the top of Mt. Tam in Marin. three years ago I left a fog-shrouded city of San Francisco on a morning ride. The Golden Gate was also fog covered. And the for persisted all the way to the 2000-foot line on Mt. Tam, then it was brilliant sun all the way to the top of East Peak. I could see back to SF, but the only thing I could see was the cloud of fog that blanketed the entire city except for the peaks of the Golden Gate tower support piers and the antennas on top of Mt. Bruno inside the city.
Yesterday it was clear and cool all the way from the city through Marin up almost 2300 feet then a cloud covered the very top of the mountain. I rode the last half mile to the crest in increasingly thick fog. At the top I could not see a thing. the wisps of fog were so thick they seemed like they would hurt if they hit me. I went back down into the cloud, but a half-mile later , below and away from the cloud, the sun was shining again.