Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
111 AM EDT Tue Jun 16 2020

Valid 00Z Wed Jun 17 2020 - 00Z Wed Jun 24 2020

A relatively quiet weather pattern appears set to persist across
Hawaii into early next week. High pressure at the surface and
aloft is forecast by all guidance to remain anchored north of
Hawaii, keeping breezy trades in place, with scattered, primarily
windward showers. Models continue to show a relatively weak
easterly wave traversing Hawaii, moving west of Hawaii by later in
the week. A relatively dry air mass in place (PWs ranging from
1.0-1.5 in.) should keep any associated activity somewhat sparse,
and limit the potential for any heavy rains. Guidance shows
general consensus that as the system moves west of Hawaii, it
should cut off, and perhaps become nearly stationary for a period
of time. The implications for sensible weather across Hawaii of
this seem relatively minor - perhaps a gradual weakening of the
trades by early next week. A continued relatively dry air mass in
place across Hawaii through early next week should keep showers
relatively limited. Deterministic guidance showed some variability
on the handling of the upper low after it cuts off, but ensembles
were in relatively good agreement, so favor an approach to the
forecast heavily reliant on ensemble means with respect to that
feature over the weekend and into early next week.

Ryan