Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
827 AM EDT Tue Jun 27 2017

Valid 00Z Wed Jun 28 2017 - 00Z Wed Jul 05 2017

Models and ensembles show an upper trough moving westward later
this week (Fri into next week) just north of Hawai'i as an upper
high develops to the north and northwest of the region. Just prior
to the upper trough's approach, a surge in precipitable water is
forecast to swing through the area from the northeast as it splits
off front a frontal boundary around 40N. The upper trough itself
will maintain elevated PW values into next week.

Upper high to the north will support a surface high pressure
(about 1032-1035mb) and a stronger pressure gradient which will
increase trades next week after a brief weaker period this weekend
as the upper trough passes through. ECMWF ensembles generally
showed higher heights over the area by next Tuesday compared to
the GEFS members (00Z) via stronger ridging to the northwest and
northeast of the region. Unclear if this is more likely than the
GEFS so a blended solutions seems reasonable. 


Fracasso