Lahaina, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

761
FXHW60 PHFO 050234
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
434 PM HST Mon Aug 4 2025

.SYNOPSIS...
Trade winds will weaken to land and sea breezes by Wednesday as
remnant of former Tropical Cyclone Gil passes just north of the
state Wednesday and Wednesday night. Humidity, cloud cover and
showers will increase Tuesday night through Thursday.

&&

.DISCUSSION...
A distant 1025 mb high to the northeast will drive trade winds
through Tuesday, but will come under less influence as the
remnants of former Tropical Cyclone Gil approach Hawaii. Gil is
currently a swirl of low clouds about 800 miles east of Hilo this
afternoon, and is expected to open to a surface trough as it
passes just north of the state Wednesday and Wednesday night.
However, the low/trough will pass in between the driving
subtropical high and weaken the winds down to where nighttime land
breezes and daytime sea breezes dominate.

Gil remnants will bring cloud cover and very humid air mass
across the state. While most of the trough of what is left of Gil
will pass to the north, some of the clouds and showers along the
southern fringes will impact the islands from Tuesday night
through Thursday. Clouds and showers will focus windward at night
through this period as land breezes will suppress this across
leeward sides of the islands. Sea breezes will bring scattered
interior clouds and showers, some moderate-heavy intensity at
times.

Drier conditions return briefly with moderate trade winds on
Friday and Saturday. Long range global models currently show
another weakening tropical system, currently Tropical Storm
Henriette in the East Pacific, will pass north of the islands
from Sunday through Monday, once again disrupting trade winds and
producing warm and very humid weather. Stay tuned for weather
forecast updates as the track of this next approaching tropical
system will likely change over time.

&&

.AVIATION...
Moderate to locally breezy trade winds will gradually decrease
into the light to moderate range tonight into tomorrow. Clouds and
showers will primarily focus over windward and mountain areas, and
remain fairly light and brief due to the stable atmospheric
profile. Overall VFR conditions are expected.

Remnant moisture associated with former tropical cyclone Gil will
pass just north of the islands on Wednesday, increasing cloud and
shower coverage.

AIRMET Tango remains in effect for moderate low level turbulence
over and immediately south through west of island mountains. This
AIRMET will likely be cancelled later today as wind speeds aloft
decrease.

&&

.MARINE...
High pressure north of the state will weaken and drift eastward
through tomorrow. Trades will gradually lower through the middle
of the week as the remnants of former Tropical Cyclone Gil pass
to the northeast of the state, then strengthen out of the east
southeast late Thursday through Friday. The Small Craft Advisory
(SCA) is in effect for the windier waters and channels around
Maui County and the Big Island through 6 AM.

A moderate, long period south swell that is filling in now should
peak near High Surf Advisory (HSA) criteria this evening into
Tuesday before declining Wednesday. Another swell is expected from
a low that formed last week south of New Zealand. This swell is
expected to build in on Thursday and hold through the weekend
which could peak near HSA criteria.

Short period trade wind swell will keep east facing shores elevated
and choppy due to strong trades. Late this evening into Tuesday,
a moderate, medium to long period east swell is expected to fill
in from the remnants of Tropical Cyclone Gil and may also peak
near HSA criteria.

A small, medium period northwest swell originating from former
Typhoon Krosa in the western Pacific is bumping the surf up a bit
along north facing shores. Another bump is expected Thursday and
Friday as a small, medium to long period northwest swell looks to
fill in.

&&

.FIRE WEATHER...
Humidity levels will increase while winds speeds decrease through
Wednesday. Inversion heights will be around 5000 to 6000 feet
with very low relative humidity values at and above this
elevation. Humidity levels will increase dramatically from
Tuesday night through Thursday as the remnants of former Tropical
Cyclone Gil pass just north of the Hawaiian Islands and block the
trade wind flow.


&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 AM HST Tuesday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.


&&

$$


DISCUSSION...Foster
AVIATION...Tsamous
MARINE...Walsh
FIRE WEATHER...Foster