After trending south for awhile, the 12Z GFS has shifted back north, bring the system in just south of Galveston. It also deepens the system quite a bit more, bringing it down to 976 mb in the western Gulf and about 980 mb at landfall, which is about 10 mb lower than the previous runs. Sometimes, when the global models indicate that sort of deepening (which is unusual for them since they don't resolve the central pressure of hurricanes very well), that can indicate a significant intensification of the system and/or an expansion in the size of the system. It will be interesting to see what the other 12Z model runs have to say.