559
FXHW60 PHFO 111337
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
337 AM HST Tue Nov 11 2025

.SYNOPSIS...
A broad, building high north of the islands will produce a tight
pressure gradient leading to breezy to windy trades over the next
couple days. Enhanced shower activity and cloud coverage will
remain mainly over windward and mauka areas. As the high meanders
northeastward away from the islands later this week, trades will
weaken to a more moderate regime for the remainder of the week.


&&

.DISCUSSION...
The latest model guidance continues to support a broad, building
high situated well north of the Hawaiian Islands. Currently at
1034 mb, this area of high pressure produces a tight pressure
gradient -- the key factor in the recent breezy to windy trades
across the state and progged to prevail throughout the remainder
of the week. Trades are anticipated to be strongest on Wednesday,
as the aforementioned high is progged to build to around 1035 mb.
This has increased confidence for more widespread windy trades and
may exceed wind advisory thresholds beyond the typical wind-
prone locations. However, have opted to hold off on issuing a wind
advisory at this time for models to better assess timing and
location in a future shift. Thereafter, deterministic guidance
suggests the high will begin to weaken and and propagate
northeastward away from the islands during the latter half of the
week. Trades will respond accordingly, weakening as well, though
is expected to remain moderate to locally breezy.

Throughout the week, the enhanced trades will bring periods of
shower activity, particularly across windward and mauka areas
across all islands. Latest model guidance has depicted a weak low
and associated frontal boundary developing east of the island
chain early Wednesday that is set to meander further eastward and
dissipate. Prior to dissipating, however, moisture associated with
the frontal boundary gets embedded in the enhanced trade wind
flow, suggesting an uptick in shower activity along windward and
mauka areas, namely across Maui and the Big Island. Latest GFS
total precipitable water (PWAT) Normalized Anomaly depicts
PWATs to be 1 to 2 standard deviations above normal during this
time. Conversely, the ECMWF isn`t quite as high, but still remains
wetter than normal, showing 0 to 1 standard deviations above
normal. Either way, expect windward trade showers to be prominent
throughout the middle of the week, then gradually lessen through
the weekend.

A slightly drier air mass will keep dew points in the low- to
mid-60s through the next several days, presenting a more Fall-like
ambiance across the islands. Relative humidity values may take a
brief hit today and tomorrow, with values falling below 50 percent
today, predominately across leeward Big Island, recovering back
above 50 percent as the week progresses as additional moisture
moves into the state.

In the longer range, by early next week, some model guidance
indicates an influx of an abundance of moisture will be pulled
northward and engulf the Hawaiian Islands as a surface trough
produces southerly flow. Model PWAT Normalized Anomalies during
this time are suggesting PWAT values upwards of 3 standard
deviations above normal; the first indication that heavy rainfall
may be in the future. However, confidence remains low at this
time, given the long lead time before the event. That said, future
shifts will need to monitor model trends to determine how
accurate this initial assessment proves to be.


&&

.AVIATION...
Breezy to locally windy trades persist through the day, leading to
embedded clouds and enhanced shower activity over windward and
mauka areas. MVFR conditions are possible in heavier showers.
Otherwise, VFR conditions prevail.

AIRMET Tango remains in effect for mechanical turbulence to the
lee of the mountains of all islands due to the breezy trade winds.
This is expected to continue through the next couple days.


&&

.MARINE...
A strong ridge of surface high pressure, centered roughly
1000 nm north of the islands will maintain fresh to strong trades
across all marine zones today. In addition, combined seas are
expected to surpass 10 feet for windward marine zones and through
island channels. Trades are then forecast to further increase
tonight through Thursday and become strong to near gale force. A
Gale Warning may be need during the peak of the event for the
typically windy waters surrounding Maui and the Big Island. The
high will gradually drift eastward and weaken Friday, leading to
moderate to fresh trades through this weekend.

A short to moderate period, north- northeast (020-030 deg) swell,
generated from strong trades near and upstream of the islands,
will produce large and rough surf above High Surf Advisory (HSA)
levels along north and east shores today. The northerly component
to the swell, at least to start the day (before the swell
direction becomes more northeasterly), will allow for surges at
north facing harbors, mainly Hilo and Kahului. A Marine Weather
Statement remains in effect to highlight this. In addition, a
combination of higher than predicted water levels, large breaking
waves, and strong onshore winds could lead to significant wave
runup, beach erosion, and localized coastal flooding near this
mornings high tides for north and east facing shores, then mainly
for east facing shores thereafter during daily peak high tide
cycle. The HSA will likely be dropped for north facing shores
tonight and extended for east facing shores through at least
Wednesday night, as large waves and choppy conditions persist from
strong to near gale force trades around and upstream of the
islands. The advisory may need to be upgraded to a warning during
the peak of the event on Wednesday, as surf heights approach
warning criteria of 15 ft. Northeast swell energy lowers on
Thursday as local trade winds begin to decline, with east shore
surf steadily dropping Friday through the weekend.

A pulse of long period south swell energy has arrived and can be
noted on the near shore buoys this morning at around 3 feet 14
seconds. This swell is progged to peak slightly higher late today
into Wednesday, then begin to fade by Thursday. This late season
energy should help bump surf up to near or slightly above the
November average. South shore surf returns to near flat Friday
into this weekend.


&&

.FIRE WEATHER...
Breezy to locally strong trades will continue across the state
through the week. Relative humidity may briefly fall into the mid-
to upper-40s today for isolated leeward areas, however, low-level
moisture embedded within the trades should prevent this from
being widespread. Additional areas of moisture moving into the
state should help to keep relative humidity from reaching critical
thresholds for the remainder of the week. Inversion heights will
remain around 6,000 to 7,000 feet today.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 PM HST this evening for Niihau-Oahu
North Shore-Olomana-Maui Windward West-Kauai North-Kauai East-
East Honolulu-Koolau Windward-Molokai Windward-Molokai Southeast-
Molokai North-Maui Central Valley North-Windward Haleakala-
Kipahulu-Big Island East-Big Island North.

Small Craft Advisory until 6 AM HST Thursday for all Hawaiian
waters-


&&

$$


DISCUSSION...Pierce
AVIATION...Pierce
MARINE...JT
FIRE WEATHER...Pierce