Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
154 PM EST Thu Mar 08 2018

Valid 12Z Mon Mar 12 2018 - 12Z Fri Mar 16 2018

Big picture remains relatively similar to yesterday, with a slowly
moving upper trough/low well south of the Gulf of Alaska and
another over northeastern Russia. Ridging will attempt to hold as
it pokes into the AkPen but is squashed a bit by incoming systems.
Timing these systems out of the North Pacific or northeastern Asia
remains a challenge, and even the ensembles have shifted
noticeably in the past 24 hrs regarding which system to favor for
development at the expense of another. Attempted to mitigate large
changes in continuity via the 12Z GEFS mean and 00Z NAEFS mean as
the 00Z ECMWF ensemble mean seemed to be lagging the GEFS changes
by a cycle or two. However, as a low moves through the southern
Bering Sea next Wednesday, opted to favor the older 06Z GEFS mean
and take the sfc reflection eastward into the Gulf rather than
northeastward into the western interior. Below average confidence
in storm track/intensity this period as it is always a battle with
upper ridges. May need a few more model/ensemble cycles to sort
things out with limited predictability beyond about 5 days for a
while until the pattern changes.

Fracasso