Area Forecast Discussion
Issued by NWS Honolulu, HI

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661
FXHW60 PHFO 081942
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
942 AM HST Fri Nov 8 2024

.SYNOPSIS...
A remnant frontal boundary brings increased showers to Molokai and
Oahu today and Kauai late tonight into early Saturday. Stable,
breezy trades then prevail well into next week.

&&

.DISCUSSION...

Remnant frontal zone draped over western Maui County and Oahu this
morning presents as a narrow band of shallow moisture existing at
the convergent interface of breezy NE trades and building
easterlies. Satellite and radar observations confirm model
depictions of saturation up to around 8kft in the vicinity of this
boundary and low-level forcing remains sufficient to generate
widespread light showers along with spotty heavy showers along the
convergent boundary itself. This in turn spells a wet morning and
early afternoon for Molokai and Oahu, including most leeward areas
with the exception of far western Oahu which will likely escape most
shower activity given the shallow moisture profile. As governing
high pressure migrates eastward, easterlies will gradually build
across the area which will usher this band of showers westward with
time. Drier upstream air will begin working into Oahu by this
afternoon while the band approaches and eventually reaches Kauai
late tonight into Saturday.

Strong 595dm mid-level ridging is already establishing over western
portions of the area and will build eastward during the next 24-48
hours. Consensus is strong among the extended guidance that a
stable, breezy, and normal to slightly wetter than normal trade wind
pattern will continue well into next week. Further amplification
of the resident mid-level ridge axis may allow for a period of
strong trades by the end of next week.


&&

.AVIATION...

A band of moisture from dissipated front will continue to affect
portions of the state within a breezy trade wind flow. As of 930
AM, the band will be clearing Molokai within the next hour or so
and will remain focused on Oahu through noon. AIRMET Sierra for
MVFR ceilings and VIS in SHRA is posted for windward and mountain
sections of these islands, with improvement expected during the
afternoon. Expect only isolated MVFR conditions on windward
sections of the Big Island, Maui, and Kauai today. For tonight,
the moisture band will drift westward and likely impact windward
Kauai with MVFR conditions and mountain obscuration. VFR will
prevail over leeward areas.

The combination of breezy trade winds and an inversion based
between 6,000 and 8,000 feet will continue to produce moderate
low-level turbulence over and downwind of terrain on all islands
through tomorrow. AIRMET Tango is in place for this phenomenon.
In addition, a sharp upper level trough just south of the Big
Island may produce some moderate turbulence above FL350 through
midday.

&&

.MARINE...

High pressure to the northwest of the state will gradually shift
to the north this weekend and will maintain fresh to locally
strong trades through at least early next week. With the high
moving north of the state, wind direction will become more
easterly by Sunday. Small Craft Advisory (SCA) remains in effect
for many areas today and will likely drop off in some areas
tonight into Saturday as the trades fluctuate. In the extended,
there is growing confidence for trades to strengthen as a strong
high sets up NNE of the state. Widespread strong trades are
expected during the second half of next week with even gales
possible for select channels.

A reinforcing medium period NW to NNW (320-340 degree) swell
should build in later today, peak tonight into early Saturday,
then gradually decline over the weekend. A moderate NW (325
degree) swell is expected to fill in on Monday and will likely
peak near advisory levels late Monday. This swell will be followed
by a slightly larger NW (320 degree) swell on Wednesday, which
should produce advisory level surf for N and W facing shores next
week Wednesday.

Surf along east-facing shores will remain rough and choppy through
the middle of next week due to the breezy trade winds. Long range
models are showing a significant increase of windswell towards the end
of next week due a large fetch of strong trade winds setting up over
and upstream of the state. Surf could reach warning levels (15 ft)
along east facing shores towards the end of next week.

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

Also with the peak monthly tides coming up towards the later half
of next week (Nov 14th to Nov 18th) we should see coastal
inundation impacts during the early morning hours along all
coastlines. The large windswell combined with the peak monthly
tides could cause greater impacts along windward shores.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 AM HST Saturday for Kauai Northwest
Waters-Kauai Leeward Waters-Kauai Channel.

Small Craft Advisory until 6 PM HST this evening for Kauai
Windward Waters-Oahu Windward Waters-Oahu Leeward Waters-Kaiwi
Channel-Maui County Leeward Waters.

Small Craft Advisory until 6 PM HST Sunday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.


&&

$$


DISCUSSION...JVC
AVIATION...Wroe
MARINE...Kino