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000
FXHW60 PHFO 210627
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
827 PM 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 trend towards more stable conditions will last through the
weekend as high pressure begins to fill in over the islands.
Satellite imagery shows more stable looking clouds drifting near
the Hawaiian Islands this evening. That drier trend will hold into
Sunday evening. A high pressure system will build into the Hawaii
region just north of the islands from Sunday night onward.
Responding trade winds will increase into the breezy to locally
windy range for much of next week. Brief passing showers are
expected to develop as trade wind speeds increase through Tuesday.

From Tuesday night into Thursday morning, model guidance continues
to suggest that a small band of unstable clouds will move from
northeast to southwest across all islands. Expect increasing
shower trends, favoring windward and mountain areas especially in
the overnight to early morning hours. From Thursday onward, typical
trade wind weather will continue for the rest of the week with
brief windward and mountain showers possible.

Wind speeds over the highest summits of Mauna Kea and Mauna Loa
of the Big Island have fallen over the past six hours into the 35
to 45 MPH range with gusts ranging from 40 to 50 MPH. Forecast
guidance continues to show decreasing wind speed trends at summit
level, therefore the High Wind Warning for the Big Island summits
was cancelled this evening and a Wind Advisory is now in effect
for the area through early Sunday morning. Wind speeds will likely
fall further below advisory thresholds by sunrise.

&&

.AVIATION...
Light to locally moderate trades will continue through tonight
and into the coming week. Bands of low clouds and light rain
showers will impact mainly windward and mauka areas.

AIRMET Sierra for mountain obscuration has been cancelled.
However, conditions could redevelop towards morning across
windward exposures of Maui or the Big Island.

&&

.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 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...
Wind Advisory until 6 AM HST Sunday for Big Island Summits.

&&

$$

DISCUSSION...Bohlin
AVIATION...Bedal
MARINE...Shigesato