The longwave trough has continued to progress to the east and is now along the 78W longitude extending to 25N latitude where it becomes inverted into the cyclone from that point southward. This is the primary reason for the east shift in H+00 to H+48 in the GFS solution in addition to a 588 (decameter) upper ridge which earlier was centered over Jackson, MS to a position now at 27N 92W south of the coast of LA. The small upper low along the longwave trough has deepened slightly and moved north to central NC with height falls to its east and height rises to its west suggesting two things; one, the longwave trough is deamplifying with time and two, the trough is progressing eastward. The upper ridge over the GOM is progged to retrogress to the Inter-Mountain West and build, the longwave trough will continue to deamplify and the Bermuda ridge is expected to build west; this upcoming short term period suggest a NW movement through 48 hours and then a slight nudge to the west as per NHC. It remains unclear if Issac will make landfall along the extreme SE FL coast and move inland before exiting along the SW to W coast at this time. I see no scenarios where Issac is likely to be a major hurricane; at best a minimum hurricane to a strong tropical storm; it does pose a major flooding threat to parts of the northern Gulf coast and most certainly a drought buster for parts of Georgia in dire need of rainfall if this track verifies; overall no major changes in this package other than the possibility of a landfall along the SE coast.