The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or 
Though, I'm NOT expecting a widespread severe event, a few isolated thunderstorms could develop along a narrow squall line in the MA states and maybe Southern NE ...
The setup looks a little bit like a Sasquatch (Saskatchewan (spelling)) screamer and a piece of energy in the southern stream will try to phase and go NEG TILT in NE ... the ETA is more aggressive in the development and turns the deepening low sharly northward in ME ... while the GFS is not as aggressive and moves the low offshore of ME and then begins to deepen fairly quickly afterwards ....
ETA vs. GFS Side by Side Comparison
SF
