Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
806 AM EDT Wed May 10 2017

Valid 00Z Thu May 11 2017 - 00Z Thu May 18 2017

High pressure currently to the north of the state along 40N will
gradually strengthen as it settles over 40N 150W late this week
into the weekend.  From Sunday through next Wednesday expect the
high to weaken somewhat as it drifts southeastward.  This feature
will support moderate to brisk trades for most of the period. 
Precipitable water values will likely average somewhat above
normal during the period while a weakness aloft persists in the
vicinity of the islands.  As a result some of the generally
windward-focused shower activity could be on the heavier side at
times.  By next Monday-Wednesday most guidance suggests that weak
troughing aloft will evolve toward the islands from the
east-northeast.  There is some spread with this trough as the 00z
ECMWF is deeper and closer to the state with the core of the
feature than most other solutions.  The 00z ECMWF mean offers a
reasonable compromise between the 00z ECMWF and the farther east
00z-06z GFS/00z GEFS mean.

Rausch