GYX's take on the Saturday-Sunday event.
Overall models continue to struggle in the mid range due at least in
part to the transition from ridging to troughing across New England.
The GFS has been consistent for several runs with a more robust
system for late Saturday and Sunday, while the Euro has had almost
nothing across New England. However, the latest 00z run of the Euro
and the Euro ensembles show a dramatic shift from earlier thinking
toward the GFS/GEFS solutions. Meanwhile, the GFS remains consistent
with the system overall, but has trended even stronger and slightly
farther north with it.
The overall driving force for this system derives from two short
waves approaching New England, and how much they merge with each
other before moving out to sea. The latest model runs are in better
agreement in a faster second wave merging and amplifying across New
England. With this solution, it`s possible that light precipitation
with the first shortwave could break out across southern and western
areas by Saturday morning, with precip intensity increasing late
Saturday and Saturday night as the system amplifies. It`s possible
there wouldn`t be much of a break in the precip through the event if
the waves merge quickly enough.
This is a dramatic shift in the model consensus for a system
that`s only 2.5-3.5 days away. With this forecast we raised POPs
from the NBM solution to a mid to high chance for most areas,
with southern and western areas seeing a greater chance on
Saturday, while northern areas hold off until Saturday night and
Sunday. We held off on going higher on POPs to give time to
make sure this early morning`s runs aren`t just a blip.