Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
726 AM EST Sat Nov 11 2017

Valid 00Z Sun Nov 12 2017 - 00Z Sun Nov 19 2017

Latest water vapor imagery loops continue to show an active
southern stream upper level trough/low just northwest of the
Hawaiian islands. Model and ensemble solutions cluster well over
much of the next week, bolstering forecast confidence despite
transitional multi-stream amplified flow. Accordingly, a model and
ensemble composite solution is preferred.  Guidance reasonably
agrees to progress the weather focusing southern stream feature
generally eastward over the weekend as weakened lead island trades
increasingly advect deepened moisture into the state in response
to fuel some enhanced showers. The trough/low and associated
height falls are slated to dig southeastward over/east of the
state next week as an amplifying mid-upper level ridge/high
strongly builds over the north-central Pacific. This allows
infusion of some northern stream energy into the lower latitudes
whose further digging and amplification acts to steadily decrease
moisture and showers statewide later next week in the wake of
system passage. Strong high pressure building to the north of the
state in this pattern will meanwhile act to increase island trades
to moderate then brisk levels mid-late week, in a pattern with
only limited windward terrain showers.

Schichtel