Royal Kunia, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

478
FXHW60 PHFO 290133
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
333 PM HST Sat Jun 28 2025

.SYNOPSIS...
Moderate to locally breezy trade winds will persist this
afternoon, then weaken and veer out of the east-southeast late
tomorrow into early next week as a broad, weak trough develops and
moves across the area. The lighter flow may allow for some
isolated sea breeze showers across leeward areas, in addition to
the typical windward and mauka showers. Midweek and beyond, the
high to our northeast will gradually build and bring breezy trades
to the area by next weekend.

&&

.DISCUSSION...
High pressure systems far northwest and northeast of Hawaii will
maintain moderate to locally breezy trade winds through this
evening. This afternoon`s radar and satellite imagery show some
clouds and isolated showers moving into windward and mauka areas,
along with clouds and showers building over the Kona slopes of the
Big Island due to daytime heating.

A broad low level trough will develop over the islands tomorrow
into Monday as an upper level trough digs in toward the
northwestern end of the state. As a result, winds will weaken and
veer east-southeasterly. The instability provided by this weak
troughing near the state combined with pockets of moisture moving
in on the trades may be enough to enhance windward and mauka
showers during the overnight hours with some spillage over into
interior and leeward areas, and to help some clouds and showers
build over island interiors and leeward areas in the afternoons,
where any sea breezes manage to develop in the lighter flow. More
widespread sea breeze activity is expected Monday and Tuesday
afternoons, when the trade winds are expected to be at their
lightest. While the upper trough near the state may contribute to
some shower enhancement before the surface trough and associated
moisture clears the islands to the west Monday night, mid level
ridging will still be present over the majority of the state...so
not expecting a major uptick in shower activity as the weak
surface trough moves across from the east.

By midweek, the low level flow will back out of the east and
strengthen to moderate to locally breezy levels, with pockets of
moisture riding in on the trades. Heading into next weekend, the
surface high to our northeast will gradually build, strengthening
the local pressure gradient and bringing breezy easterly trades
across the island chain. Overall, typical trade wind weather can
be expected through the second half of the week with periods of
windward and mauka showers.

&&

.AVIATION...
Moderate to breezy trade winds will persist through tomorrow
afternoon and start to weaken tomorrow evening. Passing showers
will focus primarily over usual windward and mountain areas and be
a little more intense during the night time/early morning hours.
Brief periods of MVFR conditions will remain possible with any
showers but overall VFR conditions should prevail.

AIRMET Tango remains in effect for low-level lee turb.

&&

.MARINE...
Moderate to locally breezy trades are expected to persist through
tonight then gradually decrease Sunday into Monday as the ridge to
our north weakens due to a pair of troughs developing far north
and northwest of the state. The Small Craft Advisory (SCA)
remains in effect for the typical windier waters and channels
around Maui and the Big Island through tonight. Sunday will be a
borderline SCA day with winds near the SCA threshold and we may see
the SCA extended into Sunday. Early next week, with the pair of
troughs far to our north and northwest, trade winds should veer
slightly toward the east-southeast and weaken to gentle to
moderate speeds. Moderate to fresh trades could return as early as
Tuesday as the troughs move away from the area and a high builds
far north of the state.

Surf along south facing shores should see a small, long-period
south swell slowly fill in Sunday into Monday with surf peaking
near or slightly above the summertime average on Monday or
Tuesday. This swell will then gradually decline through the rest
of next week.

Surf along east shores will gradually decline over the next
several days due to the trade winds weakening. Surf along north
facing shores will remain tiny throughout next week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 AM HST Sunday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.


&&

$$


DISCUSSION...Farris
AVIATION...Tsamous
MARINE...Kino