Ripped from MA but I think this is spot on messaging. It’s an extremely delicate set-up where a 100 mile shift will make a significant sensible weather difference:
KEY MESSAGE 3...Monitoring the potential for a coastal system
this weekend.
Very favorable storm patten in terms of analogs for big snows in
the Mid-Atlantic this weekend. A 50/50 low & -NAO, Idaho Ridge,
blocking over the Hudson Bay, and trough moving into the east
Pac. Couldn`t ask for a better synoptic setup, but the formation
of a storm remains in the details of this highly sensitive
pattern.
Guidance continues to show a Miller A type Nor`easter (it has
been a while for one to form, let alone show up in model
guidance). While the ceiling is certainly high for this storm,
there is equally if not higher odds it just skirts out to see as
indicated by the latest 00Z guidance and ensembles. Future runs
will have to be seen if this is a trend or noise. How the TPV
evolves will be one of the biggest factors on if this storm
comes to fruition or not and impacts land.
Regardless, expect fluctuations over the next day or two until
the pattern is better sampled as associated energy is onshore
across the western US.