For the 19-20th potential, for now the tendency is for surface low development a little too far north and offshore. Might be a case of a little too much +PNA. Not seeing much of an indication of a shortwave taking the southern route- the primary energy would be embedded in the flow overtop the ridge. With that vortex shifting from south central Canada eastward to Atlantic Canada, NS energy associated with that may get involved a bit too late. Still almost 10 days out so plenty of time for changes in the key players.