Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
314 AM EDT Fri Mar 29 2024

Valid 00Z Sat Mar 30 2024 - 00Z Sat Apr 06 2024

Breezy to windy trades are forecast to linger today underneath a
strong surface high set up to the north of Hawaii. Meanwhile some
weak troughing aloft may decrease stability a bit and allow for
some showers. These would generally favor windward/mauka areas
with some potentially spilling leeward. By the weekend, the
pressure gradient looks to relax somewhat as the surface high
pulls northeast, leading to more moderate trades while moisture
levels dry out a bit and sit around average.

Then through early next week, models and ensembles generally now
agree that full latitude upper troughing will be likely to shift
gradually eastward across the central Pacific toward Hawaii. Into
next midweek, the base of the trough is expected to split into a
closed southern stream upper low. The position relative to the
island is less certain, but most guidance solutions now more
uniformly spin/meander the low just to the northwest of the state
into later next week. This upper flow will push a
moisture/instability pooling lead surface cold front through early
next week across the central Pacific, but suggest a slowing of the
front with approach toward the state given midweek upper flow
split/closed system development aloft. Even so, moisture is likely
to pool near and south of the front, leading to increasing rain
potential into the state into mid-later next week in a period as
another strong surface high builds to the north of Hawaii that may
act to increasing island trades again as well.

Schichtel