Consensus has been somewhat lacking but guidance has been indicating a potential system to track into Atlantic Canada later this week, towards the Friday-Saturday period, ahead of the anticipated upcoming pattern switch.
This disturbance could take a path off the US coast around Thursday before being swept into an upper trough swinging into the east and subsequently moving near or through NS and towards NL thereafter.
This is the latest from the 12z GFS @ hour 108:
Also the 12z CMC with a different take in terms of specific track, same timeframe:
The 12z Euro intensifies the system into the 980mb range on a course more similar to the GFS, adjacent to or over Cape Breton and through NL.
Low clustering from the 12z GFS ensembles @ hour 108:
Notably warmer air will make strides into parts of the east once this possible low has moved along, affecting ON & QC as well as the Maritimes into next week.
More to come on all of this and what could come next as we go, including new hints from the Euro weeklies shortly.