Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
705 AM EST Fri Nov 28 2014

Valid 00Z Sat Nov 29 2014 - 00Z Sat Dec 06 2014

High pressure initially to the north of the islands will support
brisk trades into the weekend.  Winds should become a little
lighter thereafter as the surface high weakens and tracks
northeastward, though enough trailing high pressure should exist
to support at least moderate trades through midweek.  Windward
shower activity should be fairly modest for the early-middle part
of the period with precipitable water values likely slipping below
an inch for a time around Sun-Mon. 

Latest guidance agrees fairly well that a weak/diffuse positively
tilted trough aloft should approach and reach the islands by the
latter half of the week.  This feature will likely bring about an
increase in deep moisture and to some extent rainfall.  The
approach of a surface boundary may also affect trade flow with
some locations possibly seeing more of an east-southeasterly
orientation versus east-northeasterly earlier in the period.  As
for details aloft by next Thu-Fri, would favor an average of the
00z-06z GFS/00z GEFS mean/00z ECMWF which all agree on a slightly
more amplified trough than the 00z ECMWF ensemble mean.

Rausch