638
FXHW60 PHFO 030154
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
354 PM HST Sat Aug 2 2025

.SYNOPSIS...
Breezy to locally windy trades and rather dry and stable
conditions will continue through tonight. Clouds and light
showers being carried in on the trade wind flow will remain
focused over windward and mauka areas, while most leeward areas
will remain dry over the next several days. Trade winds will
gradually ease Sunday through Tuesday and will likely be
disrupted Wednesday into parts of Thursday as the remnants of Gil
passes to our north. An increase of showers are possible
Wednesday and Thursday.

&&

.DISCUSSION...
A 1030 mb high centered far north of the state is driving windy
and dry conditions across the state this afternoon. Afternoon
soundings from Lihue and Hilo show the trade wind inversion
between roughly 5,000 to 6,500 feet. For rest of this afternoon
and tonight, we are expecting the inversion to lower slightly with
an increase of 850 mb winds. This should translate to surface
winds strengthening especially in areas downwind of terrain. With
gusty winds expected through tonight, the Wind Advisory for parts
of Maui County and the Big Island has been expanded in area and
extended through 6 am Sunday. 850 mb winds should decrease on
Sunday, which should decrease the gust factor although gusty winds
will still persist throughout the day Sunday. Shallow pockets of
moisture will be carried in with the windy trades and could
produce some light rainfall accumulation mainly across windward
slopes.

Trade winds will gradually decline Sunday into Tuesday as the high
drifts eastward and the local pressure gradient slowly relaxes. By
Monday, Trade winds should return to our typical breezy levels
with mostly dry conditions continuing to persist across the state.

Trades will likely become disrupted Wednesday into parts of
Thursday, as the remnants of Gil passes to our north. The latest
National Hurricane Center forecast remains on track with Tropical
Storm Gil weakening to a remnant low by Monday. Although there are
some uncertainty, latest model guidance continue to show the main
blob of moisture passing north of Hawaii. If this forecast holds,
the threat for heavy rain will remain low with mainly scattered
showers in the light to moderate intensity. With the trades
briefly disrupted and higher dewpoints (possibly low 70s), warm
and humid conditions are also expected during this time.

&&

.AVIATION...
High pressure far north and northeast of the islands combined
with a trough passing well to the southwest, will maintain breezy
to windy trade winds through this evening. As the pressure
gradient weakens tomorrow, winds will trend slightly lighter than
today, but should remain breezy to locally windy. VFR conditions
are expected to prevail, however some passing showers could bring
brief MVFR conditions mainly to windward and mountain areas,
especially overnight and in the early morning hours.

AIRMET Tango is in effect for moderate with isolated severe low
level turbulence over and immediately S through W of the island
mountains due to strong trade winds and gusts. This AIRMET will
likely be needed through tomorrow.

&&

.MARINE...
High pressure will remain far north of the state for the rest of
the weekend, which will support fresh to locally strong trades
across the coastal waters. Based on the latest ASCAT pass and hi-
res guidance, the Small Craft Advisory (SCA) has been expanded in
area to cover all coastal waters through tonight. The SCA will
then remain in effect for the typically windier channels and
waters of Maui County and the Big Island through Sunday as trades
begin to ease. Trades will continue to weaken through the first
half of next week as the aforementioned high drifts further east.

Surf observations from south facing shores across the state, and
trends in the Barber`s Point and Lanai nearshore buoys today,
indicate that the current south swell is continuing to gradually
decline. However, another moderate, long period, south swell is
expected to arrive late Sunday into Monday, which could boost surf
along south facing shores back up to near advisory levels early
next week. This will be followed by yet another long period south
swell arriving during the second half of the week.

East shore surf will remain elevated and choppy through most of
the day on Sunday due to locally strong trade winds. Surf along
east facing shores will begin to lower slightly as trades slowly
ease from late Sunday through the rest of the week.

Nearly flat conditions will prevail along north facing shores
through early Sunday morning. A small, long period northwest
swell originating from Typhoon Krosa in the western Pacific will
bring a small bump up in surf along north facing shores Sunday
into early next week. Another boost is possible Wednesday night
into Thursday.


&&

.FIRE WEATHER...
A gusty, stable, and rather dry trade wind flow will remain in
place through Sunday, producing critical fire weather conditions,
with winds of 20 mph or more and daytime relative humidity as low
as 35 to 45 percent. A strong inversion is in place between 5,000
to 6,500 feet, which will ensure that higher elevations of the
Big Island and portions of Haleakala on Maui experience very low
relative humidity. This inversion is expected to slightly lower
tonight into Sunday, which could increase the gusty winds downwind
of terrain especially this afternoon through early tonight. Winds
will slowly ease Sunday into Tuesday, which should cause winds to
fall below Red Flag thresholds by Monday. Although the winds
decrease, dry conditions will continue to persist through Tuesday.
An increase of humidity and shower activity will be possible
towards the middle of the week as the remnants of Gil passes to
our north.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 6 PM HST Sunday for Niihau-Kauai South-
Kauai Southwest-East Honolulu-Honolulu Metro-Ewa Plain-Waianae
Coast-Oahu North Shore-Central Oahu-Waianae Mountains-Molokai
North-Molokai West-Molokai Leeward South-Lanai Windward-Lanai
Leeward-Lanai South-Lanai Mauka-Kahoolawe-Maui Leeward West-Maui
Central Valley North-Maui Central Valley South-South
Maui/Upcountry-South Haleakala-Big Island South-Big Island
Southeast-Kohala-Big Island Interior.

Wind Advisory until 6 AM HST Sunday for Lanai Mauka-Maui
Windward West-Maui Leeward West-Kohala-Molokai Southeast-Molokai
North-Molokai West-Molokai Leeward South-Lanai Windward-Lanai
Leeward-Maui Central Valley North-Maui Central Valley South-
South Haleakala-Big Island Southeast-Big Island North.

Small Craft Advisory until 6 AM HST Sunday for Kauai Northwest
Waters-Kauai Windward Waters-Kauai Leeward Waters-Kauai Channel-
Oahu Windward Waters-Oahu Leeward Waters-Kaiwi Channel-Maui
County Windward Waters-Maui County Leeward Waters-Big Island
Windward Waters.

Small Craft Advisory until 6 PM HST Sunday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.


&&

$$


DISCUSSION...Kino
AVIATION...Farris
MARINE...Vaughan
FIRE WEATHER...Kino