http://www.nws.noaa....s_hybridaab.htm This is pretty big news thats been in the making for a while, potentially bigger than the upgrades that we saw with the GFS in previous years. While the model itself is not being modified, its data assimilation scheme is set for a big upgrade. As many of us know, its current data assimilation scheme (3DVAR) can sometimes cause the model to lag behind in the predicability standings. With this upgrade though, the GFS shifts from using a pure 3DVAR scheme to