Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
818 AM EDT Tue Mar 15 2016

Valid 00Z Wed Mar 16 2016 - 00Z Wed Mar 23 2016

Latest guidance shows better than average agreement with the
forecast pattern into the weekend.  Then some spread develops
regarding the speed/amplitude of an upper trough/leading front
approaching the area early next week.

A fast moving front will pass through late Tue into Wed.  High
pressure behind the front will support a period of northerly to
northeasterly winds.  GFS/ECMWF runs indicate that the front will
remain just close enough to the islands to keep a band of
relatively higher precipitable water values over/near the Big
Island where there may be slightly more shower activity than other
locations.  Passage of upstream shortwave energy and associated
front will bring drier air to the region during the weekend.  High
pressure to the northwest of the islands will finally move
eastward, leading to moderate to brisk easterly trades Sat-Sun. 
From late Sun into Tue the 00z ECMWF shows greater amplitude with
an approaching upper trough versus other guidance.  Thus it is
quicker to bring the leading front and moisture return into the
islands.  At this time would recommend leaning away from that
scenario, by way of a compromise among latest GFS/GEFS mean runs
and 00z ECMWF mean that lies between the GFS cluster and ECMWF.

Rausch