218
FXHW60 PHFO 250157
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
357 PM HST Sun Nov 24 2024

.SYNOPSIS...
A weak front near Kauai will move into Oahu tonight and will bring
an increase of clouds with a few light showers. This frontal
boundary is expected to dissipate near Maui on Monday. Otherwise,
expect gentle trades to return on Tuesday gradually strengthening
to moderate trades by middle of the week. A moderate trade wind
pattern is expected for the rest of the week with mainly light showers
possible over windward and mountain areas primarily during the
overnight and early morning hours.

&&

.DISCUSSION...
Latest satellite imagery shows a weak frontal boundary near Kauai,
which is producing some light showers over Kauai this afternoon.
Overall the rainfall has been unimpressive with mainly just some
light sprinkles over Kauai. This weak frontal boundary should
move into Oahu tonight with some light rain showers possible. The
frontal boundary is expected to dissipate as it moves near Maui
on Monday, but a few light sprinkles will be possible over Maui as
well on Monday. Over on the Big Island, we have a pocket of
moisture that has been lingering over windward Big Island which
will continue to produce some showers through tonight.

After the front dissipates, a weak high will build just north of
the state on Tuesday and we should see gentle to moderate trade
winds return across the state by Tuesday afternoon. Trades may
strengthen a bit more Wednesday into Thursday, but generally a
moderate trade wind pattern is expected during the second half of
the week with some light passing showers over windward and
mountain areas. Leeward areas should remain mostly dry with some
light showers possible primarily during the overnight and early
morning hours. Trade may strengthen a touch more Thursday into
Friday with locally breezy trade winds possible.

For next weekend, global ensemble models are in fairly good
agreement with trades gradually weakening as a ridge of high
pressure moves closer to the state. Generally, fair weather should
persist through next weekend.

&&

.AVIATION...
Light winds will keep sea and land breezes dominant through
Monday. MVFR cigs are expected to continue affecting windward
sections of the Big Island tonight, including PHTO, with some
MVFR vsbys in showers possible at times. Conditions are forecast
to improve around daybreak Monday. Elsewhere, a weak cold front
will slide southward into Kauai this afternoon, into Oahu tonight,
then fizzle out over Maui County on Monday. Some showers along
with MVFR cigs/vsbys will be possible in windward areas in
association with the frontal passage. Otherwise VFR conditions
should prevail.

AIRMET Sierra remains in effect for mountain obscuration over
windward sections of the Big Island and Kauai. The AIRMET may
need to be expanded to include Oahu tonight.

AIRMET Tango remains in effect for moderate upper level
turbulence between FL250 and FL410 over the entire state.
Conditions should improve over Kauai by late this afternoon, but
will likely remain in place across the remainder of the state
through most of the night.

&&

.MARINE...
A weak front near Kauai this afternoon will shift slowly
southeast down the island chain tonight and Monday before
dissipating around Maui or the Big Island by Tuesday. Winds will
remain light and variable during this time with land and sea
breezes developing near the island coastlines. Isolated showers
are expected preceding the frontal passage with gentle northerly
winds behind the front. A weak area of high pressure will build in
north of the islands around the middle of the week, bringing a
return of light to moderate trade winds. By late Thursday,
easterly trade winds look to gradually increase to the moderate to
locally strong range.

The moderate medium-period northwest swell will keep High Surf
Advisory (HSA) conditions through tonight before declining
Monday. A HSA remains in effect through tonight for most north
and west facing shores.

In addition, the small medium period north-northeast swell will
gradually diminish over the next several days. A series of moderate-
sized northwest swells will persist Monday night through the end
of the week keeping surf elevated. A large long- period northwest
swell is expected Friday and Saturday and peak surf heights could
approach High Surf Warning levels.

Surf along east facings shores will remain small except shorelines
exposed to the north-northeast swell through the first half of the
week. Surf along south facing shores will remain tiny through the
first half of next week with mainly background energy.

&&

.FIRE WEATHER...
KBDI values remain elevated across leeward areas and no
significant leeward rainfall is anticipated for the next week.
Although not much rainfall is expected with the weak front, it
should bring an increase of humidities and will keep the humidities
above the critical thresholds over the next few days. We are
starting to get to the time of year, where it is harder to reach
critical fire weather thresholds due to the cooler day time
temperatures helping to keep the humidities from dropping below
45%. Critical fire weather is not anticipated this upcoming week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 AM HST Monday for Niihau-Kauai
Leeward-Waianae Coast-Oahu North Shore-Maui Windward West-Kauai
North-Molokai Windward-Molokai North-Molokai West-Windward
Haleakala.


&&

$$


DISCUSSION/FIRE WEATHER...Kino
AVIATION...Jelsema
MARINE...Shigesato