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000
FXHW60 PHFO 201939
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
939 AM HST Sat Apr 20 2024

.SYNOPSIS...
Moderate trade winds will hold through the weekend with breezy to
locally strong trades returning next week. An increase in
moisture is anticipated Tuesday into the middle of the week,
especially for the windward areas of Maui County and the Big
Island, where showery conditions will be possible.

&&

.DISCUSSION...
A 1027mb high far north of the state will steadily drift further
northeast and away from the state this weekend. This may briefly
weaken the trades a touch later today into tonight, but a new high
will rebuild north of the state Sunday into Monday and will
produce breezy trades by Monday. Looking out into next week,
breezy trades are expected through much of the week with
potentially strong trades during the second half of the week as
the high strengthens north of the state.

As far as rainfall, this morning`s satellite imagery shows
numerous showers over windward parts of Maui County and the Big
Island. For the most part, rainfall amounts have been light due to
a strong inversion at 7000 feet as shown in the Hilo sounding. We
should see a gradual decrease of showers throughout the day today,
but scattered showers will likely persist for these areas. Over on
the western half of the state, we have mostly dry conditions with
a few scattered showers over windward areas this morning. Some of
the showers impacting Molokai, is starting to drift towards Oahu
which could produce some light shower activity through the morning
for Oahu. For next week, our main moisture source looks to be the
remnants of an old frontal boundary moving in as early as Monday
night into Tuesday. This could bring some showery conditions for
windward areas, especially the eastern half of the state Tuesday
through Wednesday night. Otherwise, typical trade wind weather is
expected with passing showers from time to time.

Over on the summits of the Big Island, a High Wind Warning is in
effect through this afternoon. Winds should gradually ease through
the day, but may still be at advisory thresholds (45 to 55 mph)
through tonight. We will continue to monitor the winds at the
summits of the Big Island where it is currently blowing at 70 mph.

&&

.AVIATION...
Light to moderate trade will persist through the rest of the
weekend. Bands of low clouds and light SHRA will impact windward
and mauka areas. ISOL SHRA over leeward areas are possible but
will be brief and light in nature.

AIRMET Sierra for mtn obsc is in effect for windward portions of
Oahu, Molokai and Maui. Conds exp to improve this aftn.


&&

.MARINE...
High pressure building in from the north-northwest will drift east
and keep trade winds moderate to fresh through the weekend. The
ridge of high pressure should rebuild early next week, which
should produce fresh to locally strong trade winds once again.

The current south swell will hold today than steadily decline
Sunday. A series of small, medium period swells will persist
through the weekend keeping south facing shores from going flat.
Small, short- period north swell will continue into the weekend.
A larger moderate medium period north swell reinforcement will
arrive late tonight. A rise in surf overnight is expected but the
north swell looks to peak Sunday well below High Surf Advisory
levels. Surf along east facing shores will remain small but can
expect a slight increase early next week as the trades strengthen.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 6 PM HST this evening for Big Island
Summits.


&&

$$


DISCUSSION...Kino
AVIATION...Walsh
MARINE...JVC