There's a common misconception that often occurs when strong hurricanes begin to interact with mid latitude vorticity. Yes, the vorticity will shear, and ultimately weaken the storm; but there's an ugly price to pay during the early stages of that process that can turn the whole equation upside-down. Many times, including today with Isaias, shear starts to disrupt the system without truly damaging the core. The result is a tropically powered core with bursts of new convection surrounded by dynamically enhanced features producing their own chaos. In other words, the system actually gets more dangerous during the first handful of hours during this process, not less. The key then becomes: "Where does the landfall occur in relation to this timing?" If it's delayed enough, nobody on land ever feels these consequences. But if landfall occurs during the height of this transformation, people end up stunned by the ferocity of the storm. The most famous and extreme example of this (nothing like this will happen today) is the 1938 hurricane, which produced its highest recoded wind gust of 186mph not on Long Island, where the storm made landfall, but way over near Boston at the Blue Hill Observatory in eastern Massachusetts. That's the power of mixing a major hurricane with mid latitude vorticity! And it remains one of the most awesome and misunderstood phenomenons in weather. Right now, Isaias is getting his own shot of adrenaline from a decent dose of vorticity. So the question is: "How long does that last before the core collapses?" It's a race between this and the moment of landfall, and by the look of things, it's going to be a photo finish!