021
FXHW60 PHFO 070658
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
858 PM HST Wed Nov 6 2024

.SYNOPSIS...

A weak front will stall and dissipate across the islands trough
tonight. This will boost trades into the breezy to locally windy
category into the weekend. Breezy trades with periodic showers
will continue into next week. An upper level low developing
southeast of the Big Island this weekend may help to enhance
trade wind showers.

&&

.DISCUSSION...

Satellite and radar imagery show a weak front draped across the
central islands, with persistent showers streaming in to all but
Kauai this evening, due to it being the only island on the dry
side of the front. Locally strong northeast winds are filling in
behind the front along with strengthening northeast trades ahead
of it, the latter of which will continue to deliver persistent
showers to Oahu through the Big Island through tomorrow, even as
the front dissipates across the area. Most of these showers are
passing over the island terrain of the central islands, bringing
wet conditions across windward, mountain and leeward areas. If
these showers continue to train over the same areas bringing
persistent moderate to heavy rainfall, localized flooding will be
possible through the night, particularly across the central
islands where the axis of moisture seems to be focused.

Breezy trades will continue through the rest of the week and into
the weekend as the high remains anchored to the northwest and
batches of moisture are pushed in on the trades, bringing periodic
showers to the islands. With upper level troughing overhead, this
may help to enhance trade wind showers.

Models show an upper low will dig southeastward to a position
southeast of the Big Island late this week and into the weekend.
However, models differ a bit on the strength and positioning of
this upper feature as well as on the available atmospheric
moisture. Available moisture may be the limiting factor in shower
development through the weekend and into early next week, making
pin pointing where showers may fall across the island chain a bit
tricky. But as batches of atmospheric moisture move through,
combined with increased instability from the low aloft, we`ll
likely see enhanced trade wind showers this weekend into early
next week.

&&

.AVIATION...
A shallow band of moisture accompanying a cold front near Oahu
this evening, combined with the gusty northeast winds, will
continue to generate showery conditions over windward slopes from
Oahu to the Big Island. These conditions support AIRMET Sierra
for mountain obscuration remaining in effect through Thursday for
these areas. Drier air trailing the front has moved over Kauai,
which will limit cloud/shower coverage.

AIRMET Tango remains in effect due to low-level turbulence over
and downwind of terrain, which will continue through Thursday.
Moderate turbulence between FL250 and FL350 associated with an
upper trough is also expected through the period.

&&

.MARINE...
A front will move into Oahu tonight, then stall out and gradually
dissipate in the vicinity of Maui County through the end of the
work week. Strong high pressure is building in behind the front to
the distant northwest, with this high expected to lift northeast
over the weekend. Trade winds will remain steady at fresh to
strong levels through early next week, with some of the windier
channels seeing near Gale force winds at times. A Small Craft
Advisory is now in effect for most waters through 6 PM Friday. The
SCA will likely need to be expanded to include a portion of the
marine area through early next week.

Surf along north and west-facing shores will trend up this
evening as a new north-northwest swell builds. This swell will
peak late tonight and Thursday, then slowly lower through Friday.
A new long-period northwest swell will arrive late Friday, keeping
surf up through Saturday, before slowly lowering on Sunday. A pair
of back to back moderate sized long-period northwest swells will
arrive during the early to middle part of next week, with the
latter swell potentially bringing advisory level surf to north and
west facing shores next Wednesday.

Surf along east-facing shores will remain elevated and choppy
through the middle of next week due to the strong trade winds.

Surf along south-facing shores will remain small and near the
seasonal average through the middle of next week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST Friday for Kauai Northwest
Waters-Kauai Windward Waters-Kauai Leeward Waters-Kauai Channel-
Oahu Windward Waters-Oahu Leeward Waters-Kaiwi Channel-Maui
County Windward Waters-Maui County Leeward Waters-Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.

&&

$$

DISCUSSION...Farris
AVIATION...Gibbs
MARINE...Jelsema