Kaiminani, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

722
FXHW60 PHFO 180641
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
841 PM HST Fri Jan 17 2025

.SYNOPSIS...
A weak cold front, currently located over the eastern end of the
state, will bring periods of showers as it continues to advance down
the island chain overnight. Much cooler and drier conditions are
expected in the wake of the front, followed by a more typical trade
wind pattern leading into the work week. Rainfall chances could
increase once again around midweek, as another cold front moves into
the area.

&&

.DISCUSSION...

Latest satellite imagery pinpoints a weak and deteriorating cold
front near Maui, bringing a brief period of
showers to windward Maui and portions of the Big Island,
as it continues southeastward. The front
is expected to clear the Big Island early Saturday morning.
Dewpoints have already dipped into the 50s on Kauai and are expected
to fall into the mid- to upper-50s across the region as a much
cooler and more stable airmass fills in behind the front.
Moderate to locally breezy northerlies are being advected across the
region. This combined with the very dry air brings a low probability
of fire weather concerns during the afternoons over the weekend,
with the primary factor in the lowered probabilities being that
winds fall short of the threshold.

As the remnant trough and associated cold front exit the region,
the latest analysis continues to showcase a broad, mid-level ridge
anchored just to the west, anticipated to build eastward toward
the islands. Trade winds reestablish themselves shortly
thereafter, with the winds veering northeastward and leading to a
return of windward and mauka showers. Stronger model consensus
displays a strong mid- latitude disturbance, weakening the trade
wind pattern and bringing another cold front to the forecast area
by midweek. However, there remains quite a bit of uncertainty
given the development and timing of the mid-level wave, ranging
from a benign, progressive frontal passage, as portrayed by the
GFS, to a well-developed Kona low as shown by the Euro. Further
model runs will be required going forward to hash out the details
for next week.

&&

.AVIATION...

A shallow cold front will continue to break apart as is moves
through Maui and along the Hamakua Coast of the Big Island
tonight. Low clouds and enhanced showers remain in the forecast
for both islands, with brief MVFR conditions are possible for
these areas through the early morning hours on Saturday.
Northeasterly winds will build in behind the front, with cooler
and drier conditions expected for the weekend.

AIRMET Sierra was issued this evening for mountain obscurations
producing low cloud ceilings along the north and east sections of
Maui. This AIRMET will continue through the overnight hours, and
may expand in coverage to the north and east slopes of the Big
Island later tonight.

&&

.MARINE...

A cold front is currently passing into the Alenuihaha Channel as
it advances east into Big Island later this evening. Thunderstorms
in association with the front are impacting the far eastern
offshore waters and storms will continue to move east of the area
with the exiting front. High pressure building in behind the front
this weekend will strengthen trade winds. Moderate to locally
strong trades will occur from Saturday night through early Tuesday.

A large, long period northwest (300-320 degree) swell is peaking
this evening. The nearshore Hanalei buoy is currently depicting a
15 foot 17 second swell that is likely producing XL 30 to 40 foot
surf along Kauai`s north shores. The far northwest buoys have
displayed a steady decline of the swell through the day and this
will translate to slowly declining surf into dawn. The swell
should drop surf to borderline warning levels by mid-Saturday.
A High Surf Warning remains in effect for the north and west-
facing shores of Niihau, Kauai, Oahu, Molokai, along with north
facing shores of Maui, through Saturday afternoon. Surf should
peak tonight into early Saturday morning for the west-facing
shores of the Big Island. Due to the westerly component of this
swell, a High Surf Warning remains in effect for the west-facing
shores of Big Island through Saturday. A Small Craft Advisory is
also in effect for elevated seas brought on by the passing large
northwest swell. The next northwest swell is scheduled to arrive
next Tuesday into Wednesday and this could create advisory level
surf along many north and west-facing shores.

An out-of-season south swell is filling in this evening and is
producing summer average surf. This swell is expected to peak
tonight then gradually decline this weekend. Surf should return to
background levels, or be nearly flat, by the middle of next week.

East-facing shore surf will become more choppy the next couple of
days as a result of moderate post-frontal trade flow. East shore
surf becomes more rough Sunday and Monday in response to
strengthening northeasterly trades. Select northeastern to eastern
exposures may experience some wrap from the passing large northwest
swell.

&&

.FIRE WEATHER...

Moderate to locally breezy north to northeast winds will funnel
drier air into the area for the weekend. The probability for
critical fire weather conditions to develop is low, mainly owing
to winds failing to reach the threshold. The greatest probability
for Red Flag conditions to develop is Sunday.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Warning until 6 PM HST Saturday for Niihau-Kauai
Leeward-Waianae Coast-Oahu North Shore-Maui Windward West-Kona-
Kohala-Kauai North-Molokai Windward-Molokai North-Molokai West-
Maui Central Valley North-Windward Haleakala-Big Island South.

Small Craft Advisory until 6 AM HST Sunday for all Hawaiian
waters-


&&

$$


DISCUSSION...Pierce
AVIATION...Bohlin
MARINE...Blood
FIRE WEATHER...Pierce