Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
243 AM EST Thu Dec 05 2019

Valid 00Z Fri Dec 06 2019 - 00Z Fri Dec 13 2019

From late Thursday into Friday a shortwave aloft dropping
southeast across the state will promote a brief period of enhanced
rainfall (snow at highest Big Island elevations).  Guidance has
become more agreeable and consistent in tracking the heaviest
activity to the south of the main islands, but still by a small
enough margin that it requires ongoing monitoring.  Weakening high
pressure initially north of the state and tracking southeastward
will support enough trade flow to focus highest rainfall totals
over windward locations.  The weekend will bring a drier trend
along with a trend to more land/sea breezes as high pressure
reaches the eastern Pacific and a front approaches the
northwestern islands.  Guidance maintains modest differences for
exact frontal position but as a whole is more agreeable and
consistent than in previous days.  Consensus shows this front
reaching very close to the northwestern islands before
weakening/lifting northward.  Expect weak high pressure behind the
front to revive the trades for Monday-Tuesday while moderate
moisture and ridging overhead should lead to mostly light shower
activity.  Another front will likely approach the area
Wednesday-Thursday as an upper trough amplifies to the northwest. 
This front, which shows better than average agreement and
continuity among the models/means given the distant time frame,
would bring another disruption to the trades and potential for
increased rainfall.

Rausch