Area Forecast Discussion
Issued by NWS Honolulu, HI

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622
FXHW60 PHFO 120129
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
329 PM HST Sat Oct 11 2025

.SYNOPSIS...

A surface trough just to the north of the state will help bring
relatively light winds today. A significant upper level low
approximately 1000 miles north of the islands will move south
through midweek. Models indicate it could move very close to or
perhaps even over the state. This will increase instability and
introduce a chance for stronger showers and a few thunderstorms.
East to southeast surface winds continue, becoming stronger from
Wednesday into next weekend.


&&

.DISCUSSION...
Relatively light surface winds have allowed sea breezes to develop
again today, although not as strong as yesterday. Isolated to
scattered showers were developing statewide as of 3 PM HST. These
are forecast to last into the early evening hours before
diminishing rapidly after sunset.

A strong upper level low dropping south toward the state will
help determine our weather for the coming week. As this low
approaches and brings cooler air aloft, the atmosphere will
become increasingly unstable. Low-level moisture is also forecast
to increase Monday. These factors will combine to favor a few
stronger showers and most likely a few thunderstorms after
Tuesday. Thunderstorms may develop as early as Tue night, but
probably not until Wednesday/Thursday. Conditions will remain
favorable for thunderstorms through at least Friday. Models do
have some important differences in timing/location of this
feature, so we agree with the previous forecast in not attempting
to nail down exact thunderstorm locations this early. However,
confidence is increasing that at least a few thunderstorms will
form next week (most likely over the western half of the state).


&&

.AVIATION...

A trough north of the state is resulting in light E to ESE winds
across the island chain today. For some locations, this has
resulted in variable winds, switching between easterly trades and
onshore sea breeze winds. Clouds and showers remain limited
overall, though some clouds and showers will remain possible
through early evening over island interiors and select leeward
locations. VFR flight conditions are expected to prevail for most
areas. This same pattern will persist into Sunday, with light
background winds and sea breezes increasing interior clouds and
showers during the day. Overnight, land breezes are forecast to
diminish cloud cover over the islands.

There are currently no AIRMETs in effect, and none are
anticipated at this time.


&&

.MARINE...
Broad troughing north of the islands will keep the local pressure
gradient somewhat weak, maintaining mainly gentle to moderate
trade winds over coastal waters into Tuesday. The trough will
gradually fill late Tuesday and Wednesday, and building surface
high pressure north of 30N will drive strengthening trade winds.
Small Craft Advisory conditions may develop over the typically
windy waters around the Big Island and Maui as early as
Wednesday night and likely by Thursday. As trades strengthen, a
disturbance aloft will drift southward over the islands and bring
instability.

Small north shore surf today will give way to a long lived event
Sunday. Currently, a mix of building medium period northwest
swell and short- to medium-period north-northeast swell is
producing small surf along north facing shores. The north-
northeast swell will fade tonight as the northwest swell picks up
slightly. Long-period forerunners of a new northwest (320 deg)
swell will build on Sunday, and surf should peak at High Surf
Advisory levels Monday and Tuesday for most north and west shores
from Kauai to Maui. Surf will gradually decline Thursday and
Friday, with some small northwest swell lingering into next
weekend.

Small inconsistent southwest swell will decline by Monday, with
tiny background swell prevailing through the rest of the week.

Along east facing shores, the small north-northeast swell will
fade overnight, but a slight increase to near seasonal normal is
expected tonight into Monday as medium-period easterly swell from
a distant tropical cyclone moves across the area. Low swell
energy from the east is already on the rise at the Hilo PacIOOS
buoy and should slowly build overnight. East shore surf will be
small Tuesday, then increase and become rough during the second
part of the week as trade winds build over and upwind of the
islands.

Water levels during morning high tides will continue to gradually
lower during the next couple of days. Since water levels peaked
just below the flooding level at most stations today, the Coastal
Flood Statement has been canceled. However, conditions will be
borderline at the Honolulu station Sunday morning.


&&

.FIRE WEATHER...

Light winds and isolated to scattered showers will help maintain
fire weather below critical thresholds for the next several days.
Inversion heights will range from 7,000 to 8,500 feet.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$


DISCUSSION...Parker
AVIATION...Vaughan
MARINE...Wroe
FIRE WEATHER...Parker