When a storm moves with the shear. Its actually in a Supreme environment for intensification, why a ENE heading at any point will blow it up like Micheal, or Charley did, they turned with it. Irene in 1999 was supposed to go up ft.myers Tampa but turned east with it. Also frictional effects from land. The north gets dragg by wind coming off Florida peninsula. And the south clear over water pushes the center into the coast , then once that coefficient equalizes over land north push continues. Also the drag adds a sort of tightening to the whole structure why, I believe land can sometimes aid in structural organization of system... time and time again a system wraps up tight just as it's coming ashore. Not always but enough.