187
FXHW60 PHFO 240147
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
347 PM HST Sun Aug 23 2026

.SYNOPSIS...
Locally strong and gusty trade winds will ease slightly on Monday
as Tropical Storm Moke passes several hundred miles south of the
islands. Moisture along the northern periphery of Moke will bring
wet conditions and a risk of flash flooding on the Big Island,
while less rainfall is expected to impact windward sections from
Maui to Kauai over the next couple of days. Trade winds will
drop to moderate strength on Tuesday as Moke moves westward away
from the area, with drier trade wind weather returning for the
remainder of the week.

&&

.DISCUSSION...
Locally strong and gusty trades winds continue statewide, and wet
conditions prevail on windward Big Island as moisture along the
northern periphery of Tropical Storm Moke brushes the southern
end of the island chain. The exposed low level center marking the
center of Moke is currently centered over 300 miles south-
southwest of Kailua-Kona, while deep moisture being sheared to the
north of the system is largely skirting just south of Big Island.
This has kept rainfall on windward Big Island at light to
moderate intensity today, limiting rainfall to less than one inch
during the past 12 hours and less than a half of an inch in Kau
and much of windward Maui. While the wind field surrounding Moke
is well south of the islands, the tropical storm is helping to
produce a rather tight pressure gradient over the state. The
resulting breezy trades are enhanced over and just south of
terrain, especially on portions of Big Island and Maui County
where gusts of around 50 mph are supporting a Wind Advisory.

A flood threat will continue for the Big Island through Monday,
and winds will remain elevated through this evening. As Moke
continues to move westward, low- to mid-level flow on the Big
Island will shift out of the east to east-southeast, which could
optimize orographic lift and increase rainfall on windward and
southeast slopes. The guidance continues to show large variation
in potential total precipitation, meaning that confidence is lower
than normal, but the main window for flooding will be through
early Monday morning on windward areas, with a chance for spotty
afternoon showers to produce localized flooding across the Kona
Districts. A Flood Watch is posted for Big Island through Monday
afternoon. Elsewhere in the state, expect somewhat wet conditions
windward, with passing showers leeward on gusty trades. The Wind
Advisory for portions of Big Island and Maui County has been
extended through midnight to account for lingering strong winds
this evening. Later tonight and Monday, trades will gradually
lower as departing Moke allows the local pressure gradient to
slowly relax.

Drier conditions will develop on Tuesday as trades fall to
moderate strength. Expect much of the coming week to feature
typical trade wind weather, with showers favoring windward
slopes.

&&

.AVIATION...
Tropical Storm Moke was centered nearly 300 hundred miles south
of the Big Island and continued on its westward track. Rain bands
from the tropical storm will impact windward Big Island through
tonight, which will bring MVFR and periods of IFR conditions to
the area.

Trade winds are expected to be moderate to locally strong
statewide. Outside of windward Big Island, showers embedded
within the trade wind flow will primarily impact windward and
mountain areas, bringing periods of MVFR conditions. Otherwise,
VFR will prevail.

AIRMET Tango is in effect for low level turbulence downwind of
terrain due to the strengthened trade winds. AIRMET Sierra is in
effect for mountain obscurations over windward portion of the
islands. An AIRMET for IFR conditions over portions of windward
Big Island is also a possibility tonight.

TC SIGMET series XRAY covers Tropical Storm Moke and its
convection.

&&

.MARINE...
Fresh to locally strong winds will hold across all waters through
tonight as Tropical Storm Moke passes far south of the island
chain and a broad high pressure remains north of the state. A
Tropical Storm Warning is in effect for the offshore waters.
Intense convection associated with this storm will remain over the
southern portion of the offshore waters as this system tracks west
and exits the region by Monday. A Small Craft Advisory (SCA) for
all waters has been extended through 6 AM HST Monday. Some areas
of the coastal waters should drop out of the SCA Monday as TS Moke
shifts west of state easing the pressure gradient across the
state. Moderate to locally strong trades should return by Monday
night or Tuesday.

Higher winds and short period wind wave swell generated by TS
Moke appears to have peaked over the eastern half of the state.
Surf along east and east-southeast facing shores should trend down
a notch by Monday as TS Moke tracks west of the state but will
still be elevated and choppy and strong trades hold.

Surf along most south-facing shores will be slightly below summer
norms but still remain somewhat elevated due to a lingering small,
long period south southwest swell. A three to four foot, medium to
long period south swell is expected to arrive Monday and Tuesday
which will maintain these near summertime heights.

Small, medium to long period west to north swell originating from
Hurricane Lala is passing around north and west-facing coasts has
peaked and should trend down Monday.

&&

.FIRE WEATHER...
Locally strong and gusty trades will ease later tonight and
Monday, while humidity remains higher than normal due to moisture
on the northern periphery of Tropical Storm Moke brushing the
state. Heavy rain is expected on windward and southeast slopes of
the Big Island, while lower rainfall totals are expected over
other windward areas. The inversion will be weak to non-existent
into Monday. A typical summertime trade wind pattern will return
by Tuesday.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until midnight HST tonight for Lanai Mauka-
Kahoolawe-Maui Leeward West-Kohala-Big Island Interior-Molokai
Southeast-Molokai North-Molokai West-Molokai Leeward South-Lanai
Windward-Lanai Leeward-Maui Central Valley North-Maui Central
Valley South-Windward Haleakala-South Haleakala-Big Island South-
Big Island Southeast-Big Island North.

Flood Watch through Monday afternoon for Big Island-

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

&&

$$

DISCUSSION...Wroe
AVIATION...Munroe
MARINE...Almanza
FIRE WEATHER...Wroe