Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
808 AM EDT Sun Aug 18 2019

Valid 00Z Mon Aug 19 2019 - 00Z Mon Aug 26 2019

The models indicate a low to mid level ridge building north of the
islands early this week. Trades will be become moderate to
occasionally strong.  Expect terrain-enhanced showers with
slightly higher amounts in windward terrain of the big island and
Maui.

A tropical wave is forecast pass across the southern islands and
waters further south toward the middle of the week.  An increase
in precipitable water can be expected Tuesday night into
Wednesday, particularly on the big island.  This should result in
more showers, with a focus on the southern islands.

At the end of the week, the tropical wave is expected to pass west
of the islands. The moisture plume should depart with the wave,
with a drying trend aloft next weekend and down tick in shower
coverage/amounts as mid level ridging north of Hawaii suppresses
the deeper moisture to the south. 

Petersen