684
FXHW60 PHFO 261310
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
310 AM HST Sat Jul 26 2025

.SYNOPSIS...
A surface trough approaching the state from the east will result
in gentle to moderate trade winds this weekend. The trough will
bring an uptick in clouds and showers to the windward and mauka
areas. Expect trades to strengthen to moderate levels Tuesday or
Wednesday.


&&

.DISCUSSION...
A surface trough to the east of the islands continues to advance
towards the islands this morning. The trough will likely dissipate
before it reaches the islands, however remnant moisture
from the trough will continue to be carried into the islands on
the trade wind flow. This will more than likely increase the
clouds and showers over the windward side of the Big Island this
afternoon, and spread to the other islands later tonight and
Sunday.

There is good model agreement with high pressure building back in
to the northeast of the state early next week, which will allow
the trade winds to strengthen back to moderate to locally breezy
levels by midweek. However, there remains some uncertainty with
regards to the potential for tropical development south of
Hawaii, which could factor into how much the trades strengthen.
At the same time, a drier airmass is expected to return to the
islands.

&&

.AVIATION...
A surface trough to the east of the state will continue to move
towards the islands, which will help to weaken trades to gentle to
moderate levels for the weekend. While most of the state will
continue to experience a relatively dry and stable airmass today,
the trough will likely bring an increase in clouds and some
showers to the Big Island this afternoon, and other parts of the
state tonight and Sunday.

Predominately VFR conditions are expected to prevail, however
brief periods of isolated showers remain possible over the
windward areas of the islands. As the trough moves over the
islands, some MVFR conditions are possible over the windward sides
of the islands with the clouds and showers.

There currently are no AIRMETs in effect, and not expecting any to
be issued today.

&&

.MARINE...
Weak high pressure to the northeast of the state will allow gentle
to locally fresh trade winds through Monday. Trade winds will
gradually strengthen Tuesday to moderate to locally strong levels
as high pressure restrengthens to the northeast and also a
potential for a tropical disturbance tracking south of the waters.

South facing shores will remain small through the weekend with
mainly medium period background energy. A storm force low east of
New Zealand is producing seas up to 40 feet per JSON satellite
observations, likely impacting the islands during the second half
of next week. Confidence has increased that this low will
generate a moderate to large long period south swell that may
approach or exceeds the High Surf Advisory threshold as it peaks.

East facing shores will gradually decline this weekend as trade
winds weaken locally and upstream of the state. Flat to tiny surf
expected along north facing shores through the forecast period.

&&

.FIRE WEATHER...
Most of the state will remain in a dry and stable airmass today,
however an surface trough approaching from the east will bring
with it an uptick in clouds and showers. Winds are expected to
weaken to gentle to moderate levels today as the trough disrupts
the flow. The shallow area of moisture associated with the trough
should bring an increase in humidity late Saturday into Monday,
further decreasing fire weather concerns. Trade winds are expected
to restrengthen Tuesday or Wednesday, with developing dry
conditions reestablishing, which may result in elevated fire
weather concerns.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$


DISCUSSION...M Ballard
AVIATION...M Ballard
MARINE...Shigesato
FIRE WEATHER...M Ballard