It’s becoming more clear tonight that Hermine will have some impact on our weekend weather. What impact that is, however, remains to be seen. Our computer models agree that Hermine will lift north through Florida and track inland through Georgia and the Carolinas.
The GEFS (shown immediately above) bring the storm very close to Long Island Sunday and Monday while some of the other tropical models and the European ensembles keep the storm a bit farther south. Most of the tropical models (shown above) keep the storm off of Delaware/Maryland as opposed to the Jersey Shore. How far north the storm gets will make a huge difference locally.
The GEFS/GFS (north) solution would be similar to a moderate/strong nor’easter for Connecticut. Rain, gusty winds, and minor to moderate coastal flooding. Certainly not an Irene or Sandy but a pretty nasty storm nonetheless. A reasonable worst case scenario is sporadic power outages, locally heavy rain, and some coastal flooding on the Sound. If a farther south solution verifies then we would see only minimal impacts with clouds, a bit of a breeze, and a few showers.
By the time the storm gets close to our latitude it will be non-tropical. It will be more nor’easter-like than tropical storm-like. Instead of getting it’s energy from warm ocean waters this storm will be maintaining itself through extratropical processes (it will get its energy from baroclinic processes – meaning the storm will have fronts and be interacting with the jet stream).
So we’re relatively confident this storm won’t pass harmlessly out to sea. Someone in either the Mid Atlantic or southern New England will get a pretty nasty coastal storm for Labor Day weekend from what’s left of Hermine – what we need to figure out is which specific areas will get hit the hardest. Stay tuned!