I tend to use a number of sites if planning a passage, these being UGRIB, windguru, and also Simons weatherweb.TV (thanks again simon). When Simon talks about the forecast he usually talks about different 'weather models' and I suppose derives his forecast from these. My question is when I am looking at grib files are these raw weather models that forecasters make their assesments from, and should I trust them? If viewing Simon perhaps you could comment. Thanks