I don't think Frisco has perfect weather. The Summer is foggy all the time in the mornings and evenings, and depending on where you are the high temps are anywhere from 13 to 20 in the city. This is due to the effects of the varied topography and closeness to the Pacific Ocean. Spring is cool, less fogy but cool. Winter is cold with frequent rainstorms similar to what we saw yesterday in Israel but generally a bit less strong than. They have a "Summer" in early October where the mercury there can sore to 35 degrees or more for about two weeks. I enjoy the weather there but it often feels like you are waling out in a wet blanket all the time.