East Honolulu, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

531
FXHW60 PHFO 061950
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
950 AM HST Tue Oct 6 2026

.SYNOPSIS...
Light to moderate trade winds will produce light rainfall over
mainly windward areas into the evening. Low pressure will develop
north of the state on Wednesday, causing winds to weaken and
shift out of the south and allowing sea breezes to produce a few
interior showers in the afternoon. Deep southerly winds will draw
tropical moisture over the portions of the island chain Wednesday
night through at least Thursday, bringing some potential for
flooding rainfall. The low will weaken several hundred miles
northwest of Kauai Friday and Saturday then lift away on Sunday,
though a few heavy showers may linger through the weekend under
light winds. Light trade winds are expected to return early next
week.

&&

.DISCUSSION...
Stable trade winds will continue to slowly weaken today as a cold
front nearly 1000 miles north of Kauai pushes a surface high
eastward. A weakening low to mid level ridge over the islands will
maintain stable conditions, with small pockets of moisture
producing modest rainfall over windward areas. Aside from the
typical afternoon scattered showers over the Kona slopes, leeward
sections will be mostly dry.

Winds will weaken considerably tonight and begin to shift out of
the east to east-southeast as surface low pressure develops along
the stalling front roughly 800 to 900 miles north of Kauai. No
significant rainfall is expected, and land breezes could push most
showers offshore in the predawn hours.

The low will intensify and drift to about 700 miles north of
Kauai on Wednesday. Since this feature will be somewhat far away
from the islands, local winds will shift out of the southeast to
south but are only expected to be at gentle to moderate strength.
As a result, expect afternoon sea breezes to overpower the
background flow along north shores and generate isolated interior
showers in the afternoon. Stability will decreasing, though heavy
showers are not expected at this time.

A humid southerly flow will bring increased chances for widespread
rainfall Wednesday night through at least Thursday. The low be at
its strongest and closest to the islands at this time, possibly
within 600 miles north of Kauai. Moderate southerly flow will
draw up an area of deep tropical moisture over the islands while
a jet stream entrance region along the eastern flank of the low
provides some moist ascent. This could lead to a period of
moderate to locally heavy rainfall favoring the western half of
the island chain but possibly extending eastward to all islands.
Due to the southerly flow, leeward areas will be exposed to
potentially heavy rainfall, and while we have held off on issuing
a Flood Watch, we will be taking a closer look today. While gusty
downsloping winds are typically a concern in this setup, the flow
does not appear to be strong enough for winds to reach advisory
levels.

The low will stall and begin to gradually weaken roughly 700
miles northwest of Kauai on Friday. The jet stream on its eastern
flank will retreat north of the islands. This will reduce upper
level support for widespread heavy rainfall. However, light
southerly winds will persist, with daytime sea breezes supporting
spotty afternoon showers and dew points creeping into the mid 70s.

The humid flow will gradually shift out of the southeast on
Saturday. The GFS and ECMWF suggest that the highest rainfall
chances will be along a weak surface convergence zone near Oahu
and Kauai, and ridging aloft will build in from the east and
provide increased stability for at least Big Island. The low is
expected to fill as it lifts off to the northeast Sunday. Aside
from the possibility of variable winds on Kauai, conditions should
be similar to Saturday.

Light trade winds are favored to return Monday.

&&

.AVIATION...
Background trade winds will be weaker today, then continue to
weaken and veer more southerly tonight into Wednesday due to a
nearby surface trough. This will cause a hybrid light trade wind
and sea breeze pattern. Terrain sheltered areas will be more
likely to see afternoon cloud and shower development as a result.
Meanwhile, brief and isolated shower activity is expected over
windward and mountain areas. MVFR conditions will occur within
showers, while VFR prevails elsewhere.

There are currently no AIRMETs in effect, though mountain
obscuration could become an issue for portions of the state later
today.

&&

.MARINE...
Winds will weaken today as a low pressure system and an
associated cold front develops north of the state and approaches
from the northwest. A trough extending from this low is forecast
to move into the northwest offshore waters by Thursday. The low
will stall north of the islands and draw moisture out of the
tropics and over the area through the second half of the week, so
expect an increase in showers with moderate south to southeast
winds. The trough could potentially linger into the weekend.

Offshore buoy observations show a southerly swell around 3.5 ft with
16 second period, which will push surf for south-facing shores close
to advisory level by this afternoon and last through tonight. By
Wednesday, this swell will begin to fade. Surf is then likely to be
held near seasonal averages for the remainder of the week, maintained
by a mix of new, small south swells.

A long-period northwest swell will arrive today, pushing surf for
north-facing shores up tonight to near moderate levels on Wednesday.
Small to moderate surf is then forecast through the rest of the week
even as swell energy becomes shorter period, since it will be
reinforced by a low to the north-northwest of the Hawaiian Islands.
Surf along east facing shores will remain small as local winds remain
fairly weak.

A small, long-period west swell originating from Typhoon Choi-wan
is forecast to reach the islands Thursday into the weekend, which may
produce moderate surf for west-facing shores.

&&

.FIRE WEATHER...
Gentle to moderate breezy trades will continue a slow decline
today, with humidity just above the critical threshold this
afternoon. Fire weather risk diminishes through Friday as
southerly winds bring increased moisture and humidity. The
inversion should range from 6 kft to 8 kft today and deteriorate
Wednesday.

&&

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

&&

$$

DISCUSSION...Wroe
AVIATION...PECHACEK
MARINE...Tsamous
FIRE WEATHER...Wroe