Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
752 AM EDT Tue May 17 2016

Valid 00Z Wed May 18 2016 - 00Z Wed May 25 2016

The current Hawai'i forecast appears on-track with the newer
17/00Z cycle guidance is good agreement with this particular 7-day
period.

The 17/00Z ECENS/GEFS ensemble means and their deterministic runs
were in decent agreement through day 5 (22/12Z) over much of the
Pacific Ocean basin and North American continent. The
deterministic run and their ensemble means gradually depart over
the high-latitude northeast Pacific and Bering Sea --- with slight
variations thereafter --- along 40N 170W.

Along 40N 170W --- a vigorous cutoff is represented by the
deterministic ECMWF/GFS and the ECENS means for day 6-7. This
cutoff's migration downstream along 40N is very sensitive to a
high-latitude energy exchange over the northwest Gulf of Alaska
--- beginning around 22/12Z and the shortwave ridge solution along
50N 160W until 24/12Z.

Overall, a blend of the 17/00Z deterministic GFS/ECMWF and ECENS
means should maintain a stable medium range forecast for Hawai'i.

Vojtesak