Royal Kunia, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

131
FXHW60 PHFO 261359
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
359 AM HST Tue May 26 2026

.SYNOPSIS...
An elongated ridge of high pressure north of the state will
dominate our weather pattern through tomorrow. Stable conditions
with continued breezy to locally strong trades. A upper level low
moving in west of the islands tomorrow may pass over the state
Friday into Saturday. This feature may enhance showers.


&&

.DISCUSSION...
Hawaiian Island weather will remain very summerlike the next
several days with certain days experiencing thicker cloud cover
and slightly higher rainfall. Synoptically, there hasn`t been
much change the past couple of days. Today`s weather will be very
similar to recent days. That of breezy trades and infrequent
passing upslope windward trade belt showers that, if more
organized, may pass over the ridge tops and reach leeward areas.
Partly to mostly overcast skies over most windward sites today,
mostly sunny or clear over leeward. Afternoon temperatures will
top out near 80 F where the clouds are thickest, middle 80s over
sunny interior leeward spots. Overnights will cool into the lower
to mid 70s where most live. The highest rainfall will be confined
to east-facing terrain.

Near or sub-inch pwat morning soundings, low to mid 60 F surface
observations and water vapor satellite all support the fact that
the resident air mass is still on the dry side. While there will
be lobes of higher moisture traveling through upon breezy trades
from the east as clustered warm clouds line up east northeast of
the island chain, most of the day will remain dry with little to
no rain accumulation. The general moisture characteristics of
eastern air moving through will remain unchanged...it will be
those areas of higher moisture marching through that dictate the
haves and have nots in terms of any wetting rain. While trade-
facing slopes and upper terrain will pick up the highest daily
accumulations, there will be random spots that may pick up a
quick tenth or so, especially of those spots experiencing a
mostly sunny, very warm start to their day. It will not feel as
muggy in non-wind protected areas as winds remain breezy through
tomorrow...speeds gradually fall off later this week.

A weak upper low east of the state will move away today as a new
low to the west advances to just west of Kauai by Friday morning.
This low will pass overhead Friday into Saturday and assist in
destabilizing the atmosphere just enough, in tandem with a band
of slightly higher mid level moisture passing by from the
northeast, to garner a mention of more inclement weather from late
Thursday through Saturday. A transitory period early next week as
upper riding makes an unimpressive attempt at building in from
the west. This will leave the region under a relatively stable,
dry last couple days of May. June arrives with more sun, less
clouds/rain under weaker trades as a new surface high takes up
residence northwest of the islands.


&&

.AVIATION...
Moderate to breezy trade winds will continue for the next couple
of days. Low ceilings and passing showers will be possible over
windward and mountain locations at times, especially during the
overnight through morning hours each day. Although MVFR conditions
will be possible within passing showers, VFR will prevail for
most locations.

AIRMET Sierra is in effect for tempo mountain obscuration for N
through SE sections of Oahu this morning due to low clouds and
passing showers.

AIRMET Tango remains in effect for mod low-level turbulence over
and downwind of terrain across all islands. This AIRMET will likely be
needed through Wednesday.


&&

.MARINE...
Fresh to strong east-northeasterly trades will persist through
midweek as a strong surface ridge remains north of the state. This
will allow the Small Craft Advisory to continue across most
Hawaiian coastal waters through midweek. Expect a gradual downward
trend through the second half of the week and especially by the
weekend as a weakness in the ridge develops due to a front passing
far to the north.

A fresh long-period south swell arrives today which will slowly build
surf to near the seasonal average through Wednesday before easing
Thursday. A more significant long-period south-southwest swell is
expected by the weekend due to a storm-force low that passed
southeast of New Zealand over the weekend. Satellite data showed a
large fetch of 40 to 50 kt winds generating seas of 35 to just
over 40 ft, focused toward, or just east of Hawaii along the
190-degree directional band. Expect surf to begin building locally
Friday with 20+ second forerunners, then potentially peak around
advisory level over the weekend.

Surf along exposed north- and west-facing shores will trend up once
again today, peaking at small to moderate levels on Wednesday, before
lowering Thursday and continuing to fade through the weekend. Surf
along east facing shores will remain rough through midweek, then
gradually lower later in the week as the trades ease.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST Wednesday for Alenuihaha
Channel-Big Island Leeward Waters-Big Island Southeast Waters-
Big Island Windward Waters-Kaiwi Channel-Kauai Channel-Kauai
Leeward Waters-Kauai Northwest Waters-Kauai Windward Waters-
Maalaea Bay-Maui County Leeward Waters-Maui County Windward
Waters-Oahu Leeward Waters-Oahu Windward Waters-Pailolo Channel.


&&

$$

DISCUSSION...Blood
AVIATION...Vaughan
MARINE...Quesada