905 
FXHW60 PHFO 050138
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
338 PM HST Sat Oct 4 2025

.SYNOPSIS...
Light to moderate winds will prevail through the rest of the 
weekend. A broad surface trough will develop northeast of the 
state early next week, then propagate across the island chain. As 
this occurs, winds will weaken and become east-southeasterly, 
resulting in a daytime sea breeze and nighttime land breeze 
regime. Moderate trade winds will return near the end of next
week.

&&

.DISCUSSION...
Surface observations across the islands and an advanced 
scatterometer pass from earlier today show moderate easterly trade
winds prevailing across the region. These prevailing winds are 
just light enough to support localized sea breezes this afternoon,
which have resulted in cloud buildups and a few isolated showers 
across some leeward and interior sections of the islands. Rainfall
accumulations have been light across most of the state today, 
however, with the notable exception being a heavier shower that 
developed over the Kailua-Kona airport during the morning hours 
before it quickly dissipated. Afternoon soundings from Lihue and 
Hilo show the temperature inversion heights ranging from 6000 to 
7500 feet today, with precipitable water values virtually 
unchanged from last night, around 1.3 to 1.4 inches.

Light to locally moderate winds will continue through the rest of
the weekend. As previous discussions have mentioned, latest
global models show a surface trough developing just northeast of 
the islands on Monday, with a well-defined low aloft. This trough
will move near and then over the western islands from Monday
morning through mid-week, then will become less defined as it
weakens by mid-week. Throughout this time, background wind flow
will become weak and veer east-southeasterly. As a result, island
heating will support sea breezes each day, and overnight cooling 
will drive land breezes each night. In this patterN, daytime sea 
breezes will enhance leeward and interior shower activity, while 
land breezes overnight will clear the night skies, limiting 
showers. 

This sea breeze/land breeze regime is forecast to continue 
through latter half of the week until the aforementioned surface 
trough exits the vicinity of the islands late Friday. Moderate 
trade winds look to return to the islands next weekend. 

&&

.AVIATION...
Moderate east-northeast trade winds are expected 
through Sunday night, bringing isolated to scattered showers 
mainly over windward areas. Trade wind flow may be just weak 
enough to allow for afternoon sea breezes the rest of this
afternoon across leeward areas, resulting in clouds and isolated 
showers. Localized MVFR is possible within passing showers, but 
most sites will remain VFR. 

No AIRMETs are currently in effect.

&&

.MARINE...
Moderate east-northeast trades have filled in across the state
today and will linger through thru the remainder of the weekend as
high pressure becomes reestablished north of the area. A trough 
may develop northeast of the state early next week and move
southeast, weakening winds to light and variable through the first
half of next week.

A moderate, medium-period north northwest (330 deg) swell will  
fill in through the night and peak Sunday just below High Surf 
Advisory (HSA) criteria for north facing shores, before slowly 
fading into early next week. A small medium to long-period swell 
from the northwest (320 deg) is expected to fill in Monday, peak 
Tuesday and decline through the middle of next week.

The current small, long-period southwest (210 deg) swell will 
continue to slowly decline into early next week. A small, long- 
period southwest swell may arrive late Sunday and build into early
next week before subsiding. Another small long-period southwest 
(200 deg) swell is possible by the later half of next week. Surf 
along east-facing shores will remain below average into early next
week with the a slight boost Saturday into Sunday as moderate to 
fresh trades briefly return.

&&

.FIRE WEATHER...
Wind speeds and humidity will remain below critical fire weather 
thresholds for the next several days. Temperature inversion 
heights across the state will range from 6000 to 7500 feet through
tonight.

&&

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

&&

$$

DISCUSSION...Vaughan
AVIATION...TS/Parker 
MARINE...TS 
FIRE WEATHER...Vaughan