683
FXHW60 PHFO 250700
AFDHFO

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

.SYNOPSIS...

A weak front moving over Oahu continue to move south and
dissipate near Maui. This front will bring an increase of clouds
with a few light showers. Otherwise, expect gentle trades to
return on Tuesday and gradually strengthen to moderate levels by
middle of the week. Light showers will be possible over windward
and mountain areas primarily during the overnight and early
morning hours.

&&

.DISCUSSION...

Latest satellite imagery shows a weak frontal boundary moving over
Oahu producing scattered light showers. Rainfall totals are
expected to remain unimpressive as this front continues to weaken
as it shifts south and dissipates over Maui 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 and into Monday morning. Gentle northerly
winds will fill in behind the front this will focus isolated
clouds a limited showers mainly along northerly windward slopes.
Sheltered leeward areas will remain mostly dry overnight, but may
see a cloud or two in the morning and afternoon as seabreezes
develop in this hybrid pattern.

After the front dissipates, a weak high will build just north of
the state on Tuesday, winds will veer out of a more northeast
trade wind direction and slightly strengthening to gentle to
moderate by Tuesday afternoon. Trades may strengthen a bit more
Wednesday into Thursday to breezy levels while shifting more
easterly. Overall, 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.

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 remain in place over the islands through Monday.
This will lead to some localized land and sea breezes across the
state. The tail end of a front moving down the island chain from
the north will bring MVFR conditions with it. AIRMET SIERRA is in
effect this evening for Kauai and Oahu as the result of the band
associated with the front. Some clearing is evident on Kauai this
evening, so expecting that the AIRMET may be dropped for Kauai
later tonight, but may be needed for parts of Maui County later
tonight. The front is expected to dissipate near Maui County
Monday.

Additional low clouds near the Big Island, partially obscured by
the high clouds over Maui County and the Big Island, are producing
MVFR conditions over the windward side of the island. AIRMET
SIERRA is expected to remain in place here into Monday.

AIRMET Tango remains in effect for moderate upper level turbulence
between FL250 and FL410 from Oahu eastward, and is expected to
remain in place through most of the night.


&&

.MARINE...
Light to moderate northerly winds will fill in overnight through
Monday, then transition to moderate to fresh northeast to east
trades by midweek as high pressure builds north of the area in the
wake of a diminishing front. Expect localized wind accelerations
into the moderate to fresh category near and along some east and
west facing coasts through the late morning and afternoon periods,
while the background northerly flow persists. Winds may ease next
weekend with a potential front passing to the north.

Surf along exposed north and west-facing shores will hold near
advisory levels overnight, gradually decreasing through the first
half of the week as the current medium-period northwest (310
degrees) swell fades. A fresh, long-period northwest swell will
arrive late Monday, peak late Tuesday into Tuesday night, and then
gradually subside through Thursday. Toward the end of the week, a
larger long-period northwest (300-320 degrees) swell is expected
due to a storm-force low developing around 1500 NM northwest of
the islands this week. If conditions develop as forecast, surf
heights could reach warning levels late Friday into early Saturday
before easing gradually over the weekend.

Surf along east-facing shores will remain up through the first
half of the week as a small, short- to medium-period north-
northeast (020 degrees) swell lingers. By late week, a northeast
swell generated by strong winds north of a broad area of low-
pressure developing about 1000 NM northeast of the islands may
arrive Friday and peak over the weekend.

Surf along south-facing shores will remain near seasonal averages
this week, driven by a mix of short-period southeast and
background, long-period south-southwest swells. Early next week,
an out-of-season south-southwest swell is possible, originating
from a broad gale passing southeast of New Zealand. This active
trend may persist through the first week of December, as a
similar system passing near New Zealand is forecast to follow
later this week.


&&

.FIRE WEATHER...

KBDI values remain elevated across leeward areas. 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 North and
West facing shores of Niihau Kauai Oahu Molokai and for North facing
shores of Maui.


&&

$$

DISCUSSION/FIRE WEATHER...Almanza
AVIATION...M Ballard
MARINE...Gibbs