Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
314 AM EDT Tue May 9 2023

Valid 00Z Wed May 10 2023 - 00Z Wed May 17 2023

The elongated subtropical ridge that has been in place north of
Hawaii will continue to remain through Wednesday before breaking
down some.  The guidance agrees that a col in the subtropical
ridge develops in response to a trailing surface trough/front from
a strong low pressure system over the southern Gulf of Alaska by
late Wednesday and into Thursday.  This will likely persist going
through Saturday as well with the front likely reaching the
central Islands, but it should not have any major effects in terms
of increased rainfall.  The ensemble means suggest the high should
build back in north of the state by next Sunday and early next
week.

Mainly easterly trade wind flow of 10-20 mph with higher gusts can
be expected through Wednesday as the pressure gradient remains in
place, but a return to lighter and more variable flow is likely
for the end of the week in response to the col developing to the
north of the state.  The passage of the cold front will herald a
change to increasing northeasterly flow behind it and lower
dewpoints for the central and western Islands.  Other than some
heavier showers on the Big Island early next week, no major areas
of organized heavy rainfall appear likely over the next seven days
as the deepest tropical moisture generally stays below 15 degrees
north.

Hamrick