Area Forecast Discussion
Issued by NWS Honolulu, HI

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695
FXHW60 PHFO 081355
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
355 AM HST Mon Dec 8 2025

.SYNOPSIS...
A high pressure ridge just north of the Hawaiian Islands will
continue to weaken in advance of a cold front approaching the
islands from the northwest. Moderate trade winds will weaken and
transition to light southeasterly to southerly winds across the
region. The cold front continues to move into the western half of
the state from Wednesday to Thursday. Expect cloudy skies and
showers along the frontal band as it moves over each island with
moderate to breezy cool northerly winds blowing in behind the
frontal boundary. Light east to southeast winds will continue
through the rest of the week as yet another cold front moves into
the Hawaii region next weekend.

&&

.DISCUSSION...
Looking at this mornings satellite imagery we see a fairly stable
pattern under the influence of a weak upper level ridge. A large
band of cirrus clouds associated with an approaching cold front is
currently far northwest of Hawaii passing through Midway Atoll
this morning. This cold front will bring increasing clouds and
showers to the western Hawaiian Islands from late Wednesday
through Thursday. One wrinkle in this pattern is the presence of a
weak upper low shown on water vapor satellite imagery just east
of the Big Island. Expect one more day of easterly trade winds
with hybrid onshore sea breezes during the daylight hours along
western terrain sheltered slopes of each island. Expect brief
passing showers will remain in the short range forecast today,
favoring windward and mountain areas. Trade winds will diminish on
Tuesday with lighter southeasterly to southerly winds developing.

By Tuesday the approaching cold front will continue to break down
and drive the large scale ridge directly over the islands,
producing light southeasterly to southerly winds across the Hawaii
region. A combination of increasing stable subsidence and
southeasterly cloud steering winds will produce fairly dry
conditions across the region through Tuesday night.

From Wednesday afternoon through Wednesday night the cold front
will drift over the western islands of Kauai and Niihau, reaching
the islands of Oahu and Molokai by Thursday morning. Expect
increasing clouds and numerous showers along the frontal cloud
band as it drifts through each island. Moderate to breezy cool
northerly winds will blow in as the front passes through each
island. The latest consensus of models shows the forward motion
of the frontal cloud band stalling out over the islands in Maui
County from Thursday night into Friday morning, then the band will
diminish and lift northward as high pressure builds in to the
north of the state.

Friday through Saturday, large scale winds will remain light and
variable during this time period as a weak high pressure system,
sandwiched between two cold frontal systems passes just north of
the region. The next weak cold frontal system will approach the
state from the northwest late Saturday into Sunday. The latest
long range model guidance shows large inconsistencies on when or
if this frontal cloud band will bring another round of rain
showers to the western islands. For now the western islands of
Kauai and Niihau seem to hold the best chances for a Hana Hou
(encore) rainfall event, possibly starting by Saturday night.
Stay tuned for updates to next weekends weather conditions, as
the forecast for the western Hawaiian Islands will likely evolve
over time.

&&

.AVIATION...
Brief passing showers are possible today, mainly over island windward
and mountain areas. VFR conditions will prevail outside of
showers.

AIRMET Tango remains in effect for moderate upper level turbulence
across the island chain. This area of turbulence associated with
an upper level subtropical jet stream will move southeast
today, with this moderate turbulence area decreasing by this
afternoon.

&&

.MARINE...
An area of high pressure will remain north of the Hawaii region,
producing gentle to moderate easterly winds through today, then
decrease and veer more southeasterly to southerly Tuesday to
Wednesday as another cold front moves into the region from the
northwest. This front may move into the western Hawaiian islands
late Wednesday into Thursday, then diminish by Friday.

The current medium-period north-northwest (340-350 degree) swell
will continue to slowly fade today, bringing surf back down to
below average levels for this time of year. The next two long to
medium-period overlapping northwest (310-320 degree) swells will
arrive on today, boosting surf along north and west facing shores
and possibly reaching advisory levels by Wednesday.

Choppy east shore surf will remain small, then decline further
over the next few days as trades gradually ease. Expect minimal
background energy for south facing shores, keeping south shore
surf heights just above flat levels.

&&

.FIRE WEATHER...
Conditions remain below critical fire thresholds through the week
as winds remain light and RH elevated. Temperature inversion
heights over Maui and the Big Island will range from 5,500 to
6,500 feet today.

&&

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

&&

$$

DISCUSSION...Bohlin
AVIATION...Bohlin
MARINE...Walsh
FIRE WEATHER...Bohlin