412
FXHW60 PHFO 241309
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
309 AM HST Mon Aug 24 2026

.SYNOPSIS...

Trade winds will ease slightly today as Tropical Depression Moke
continues moving westward, south of the islands. Showers on 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 more
typical trade wind weather returning for the remainder of the
week.

&&

.DISCUSSION...

Radar and satellite imagery shows scattered showers moving across
the state. While mostly impacting windward and mauka spots some
showers are making over into leeward locations. Moke is south-
southwest of the Big Island with deep moisture sheared to the
north of the system that is mostly skirting south of Big Island.
This has kept rainfall on the lighter side with no flash flooding
threats overnight. However, a flood threat will continue through
this afternoon. As Moke continues to move westward, low- to mid-
level flow on the Big Island will veer out of the east to the
east- southeast, which could optimize orographic lift and increase
rainfall on southeast slopes. Afternoon showers could produce
localized flooding across the Kona Districts. As such the Flood
Watch will be continued through this afternoon for the Big Island.
Trades are slowly decreasing as Moke continue to move away from
the state allowing the pressure gradient to relax.

On Tuesday and through the rest of the week, a trade wind pattern
will return. Trades should be at moderate strength with typical
windward and mauka showers occurring.

&&

.AVIATION...

Tropical Storm Moke was centered nearly 400 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
the overnight into early Monday, which will bring MVFR and periods
of IFR conditions to the area. By Monday night into Tuesday, MVFR
ceilings will gradually improve to VFR by Tuesday morning across
the Big Island.

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 early this morning.

&&

.MARINE...

Locally strong trades persist as Tropical Depression Moke passes
south of the island chain and broad high pressure remains north of
the state. Convection associated with this system will remain
over the southern portion of the offshore waters as it tracks
west. The Small Craft Advisory has been extended for the typical
windy waters of Maui County and the Big Island.

Elevated winds and short period fresh swell generated by TD Moke
have peaked over the eastern half of the state. Surf along E and
ESE facing shores continue trending down as Moke advances
westward. Conditions remain choppy, however, as trades persist.

Surf along S shores remains below summer norms but still slightly
elevated due a lingering small, long period SSW swell. A 3-4 foot,
medium to long period S swell will arrive Monday into Tuesday in
maintenance of near-normal summertime surf. A similarly sized long
period S swell is then poised to arrive midweek boosting surf
toward the advisory threshold.

A small, medium to long period WNW swell originating from
Tropical Storm Lala will fade during the next 24 to 36 hours.

&&

.FIRE WEATHER...

Winds are slowly declining and will fall into the moderate
category on Tuesday. Humidity remains higher than normal due to
moisture on the northern periphery of Tropical Depression Moke
brushing the state. Heavy rain is possible this afternoon on the
southeast slopes of the Big Island and in the Kona Districts,
while lower rainfall totals are expected over other windward areas
of the state. A more typical summertime trade wind pattern will
return by Tuesday.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Flood Watch through this afternoon for Big Island-

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


&&

$$

DISCUSSION...Walsh
AVIATION...Kelley
MARINE...JVC
FIRE WEATHER...Walsh

NWS HFO Office Area Forecast Discussion