Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
343 AM EDT Wed Apr 22 2020

Valid 00Z Thu Apr 23 2020 - 00Z Thu Apr 30 2020

Hawai'i will see a more typical trade wind pattern after midweek,
with some variability in strength of the winds, as east-west
surface ridging becomes better established to the north of the
islands.  Expect the trades to continue through at least the
middle of next week.  Through the coming seven days guidance
maintains precipitable water values within a standard deviation of
normal and with a tendency to lean a bit more toward the below
normal side of the spectrum.  Thus the windward/mountain focused
showers should remain fairly light.  A front initially stalled
just to the northwest of the main islands should persist through
late week before weakening/moving westward in response to the
trades.  Then another front should come into the picture from the
northwest next Tuesday-Wednesday.  Guidance agrees that this front
should approach and possibly reach the northwestern islands by
Wednesday.  At that time the current model/ensemble spread is well
within typical error range for a day 7 forecast and there is a
fairly even distribution within the envelope.  This favors an
average of the GFS/ECMWF and their means for frontal position.

Rausch