296
FXHW60 PHFO 020230 CCA
AFDHFO

Area Forecast Discussion...CORRECTED
National Weather Service Honolulu HI
430 PM HST Sat Nov 1 2025

.SYNOPSIS...
Light to occasionally breezy trades and relatively dry through
late tonight. An approaching cold front from the northwest will
graze the Kauai nearshore waters northwest of Kauai during the day
tomorrow. The associated upper level trough or low moving in
behind the front will increase rain shower and isolated
thunderstorm chances for Kauai and its surrounding waters from
tomorrow morning through Monday morning. This system will travel
west away from the state through the middle of next week. High
pressure expanding in its wake will maintain several days of
lighter trades and lower rain chances. The greatest rain during
the majority of the week will be focused along upslope windward
mauka and within high terrain.

&&

.DISCUSSION...
A fairly dry and breezy afternoon as many sites have remained bone
dry since midnight. Only the more typically wet spots along
windward zones and over upper terrain have picked up less than a
quarter of an inch. After light and variable morning breezes,
afternoon breezy trades have returned with the notoriously windier
exposures remaining in the 10 mph gusting 15 to 30 mph realm. At
3 PM HST today, a cold front located about 400 miles northwest of
Kauai moving at a progressive clip will be in the proximity of the
far northwestern coastal waters shortly after Sunday`s sunrise.
This will significantly strengthen northeast winds over the waters
just west of Kauai and Niihau while only subtly veering light
trades more east over the remainder of the state through Sunday
afternoon. The front is forecast to stall over the far western
waters tomorrow afternoon and evening. This will have rain chances
steadily rising over the Garden Isle and Niihau over the next 24
to 36 hours.

The associated upper trough to the west of the lower level
boundary will dig down over the far northwest offshore waters
tonight. Mid to upper layers will cool and destabilize the
atmosphere over the western third of the state. Thus, the
probability for isolated thunderstorms within periods of scattered
showers with locally heavy rain exists for Kauai and Niihau
during the daytime hours tomorrow. Deterministic and ensemble
guidance from across the board all agree that a cut-off low will
pinch off from the base of this trough and travel west southwest
over the far west waters from around midnight Sunday through early
Monday. Seasonal moisture levels will be on the rise as westerly
steering flow directs a more humid southern-based air mass up and
over the state ahead of the eventually stalled front. Most of
Sunday`s precipitation will impact the western third of the state,
or mainly Kauai and Niihau, with the potential threat for locally
heavy rain that could lead to minor flooding concerns. Oahu will
also experience a more cloudy and wet day island-wide with the
windward areas of Maui County and Big Island picking up the most
rain from this early November system. The boundary layer may
become deep enough Monday to throw enough moisture atop Mauka Kea
and Mauna Loa to produce either light snow or a wintery mix (with
little to no snow accumulation) above 12k feet the next couple of
afternoons and evenings.

High pressure ridging will fill in behind the upper low as it
progressively travels west. Most island communities will enjoy
pleasant weather from Monday afternoon through early Friday as
ridging at all levels will return traditional trade weather to the
entire state. After this system heads west Monday, the main
recurring theme will be for light morning-transitioning-to-
afternoon breezy trades and light precipitation confined to
windward exposures and upper elevations. A far northern-passing
front on Friday may slightly veer and weaken trades.

&&

.AVIATION...
Trades will begin to weaken across the islands tonight as a cold
front approaches from the northwest. Expect isolated to scattered
to affect much of the area with the greatest coverage over the
western-most islands, closest to the approaching front. Some of
the more robust showers may bring brief periods of MVFR ceilings
and visibility. Expect the possibility of isolated thunderstorms
over Kauai on Sunday as conditions become less stable.

No AIRMETs are in effect and none are expected through early
tonight. However, an AIRMET for MVFR and/or IFR ceilings from
mountain obscuration may be needed for Kauai by Sunday morning.

&&

.MARINE...
A front northwest of the islands will move southeast towards the
region and displace the ridge. Isolated thunderstorms will be
possible for the northwestern coastal waters tonight as the front
approaches the western end of the state. The front is expected to
stall and then get pushed to the west as high pressure builds back
in by Monday, increasing trade winds to moderate to locally fresh
speeds. Winds are expected to remain below SCA levels until
Tuesday or Wednesday. By the later half of next week, a front
far to the north could potentially disrupt the trade winds.

The approaching front is expected to enter the offshore waters
later this evening, with strong (near gale) breezes expected over
the extreme northwest portion of the offshore waters tonight and
Sunday. The front will also bring the possibility of thunderstorms
to the offshore waters.

Surf along north facing shores will hold at HSA levels through
tonight as a medium period NNW swell (330) fills in, and a HSA is
in place for that time frame for N and W facing shores. Another
NNW swell (320-330) is expected to fill in on Sunday, followed by
a medium period NNE swell Sunday evening. The NNE swell being
associated with an approaching front with near-gale winds, that
will primarily impact the western end of the state. This mix of
swells may maintain HSA level surf through Sunday before gradually
fading early next week. The HSA may be extended through Sunday if
buoy readings remain high through tonight. A moderate to large
swell is then possible around the middle of next week.

Surf along east facing shores will remain small to moderate through
Sunday morning, and then may be impacted by the medium period NNE
swell mentioned above. South shore surf will remain small through
early next week before building slightly mid to late week as a
long period SSW swell (190) fills in across the region.

&&

.FIRE WEATHER...
Increased relative humidity values and light trades will maintain
below critical fire weather conditions the next several days.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 AM HST Sunday for Niihau-Waianae
Coast-Oahu North Shore-Maui Windward West-Kauai North-Molokai
Windward-Molokai North-Molokai West-Maui Central Valley North-
Windward Haleakala.


&&

$$


DISCUSSION...Blood
AVIATION...Thomas
MARINE...Tsamous
FIRE WEATHER...Blood