stephencanon is absolutely right about the microclimates in the Bay area. I used to live in Polk Gulch and work in the Mission. Sometimes, when I'd go to work

stephencanon is absolutely right about the microclimates in the Bay area. I used to live in Polk Gulch and work in the Mission. Sometimes, when I'd go to work at mid-day (which eliminates the possibility of time causing the change), there would be a 10-15 degree change in temperature from home to work, with complete changes in wind and fog as well. That was a 2 mile distance in a 7 mile wide city. Pretty crazy.