Yikes! No, what people call "the grib files" is the output of the Global Forecasting System which is also avaliable via any number of public service internet sources such as Buoyweater, UGrib, USGrib, etc. The GFS gives a forecast that goes way beyond a synoptic. Have a look at Frank Singleton's website - I can't give you the (rather complicated) address right now but if you google on singleton weather you will find it on clara net.

To the OP - I have only a very limited bandwidth Internet service via GPRS at the moment and cannot give a proper answer to your question as I would want to do some research first in case things have changed since I last investigated it. If I get decent Internet back in the next day or so I will try to help.