the overnight jumps up the coast to San Francisco. We set in harbor until the Sail flow indicated light winds and always had what was predicted. Where they get the data is of no concern as I'm an end result user. We were also using other sites as well but found Sailflow to be one of the easiest to use. The down side is that when we were using it they didn't have a swell report to go with it. We would have to find another site to get that information. We have been out of the country going on three years now and haven't used it lately so don't know if that has changed yet.