FXHW60 PHFO 041316
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
316 AM HST Wed Sep 4 2024

.SYNOPSIS...
Light to moderate easterly trade winds will continue through
Friday, then return to breezy levels this weekend as high
pressure builds to the north. Showers will predominantly affect
windward and mauka areas, with occasional brief showers making it
over interior and leeward locations during the afternoons due to
localized sea breezes.

&&

.DISCUSSION...
The upper ridge continues to break down this morning as an upper
trough digs southward into the region. The attendant surface
front will settle southward today, then stall and diminish into a
trough several hundred miles north of the state tonight through
the latter half of the week. This pattern transition will continue
to loosen the pressure gradient over the state, allowing the
trades to relax into the light to moderate range. The deep-layer
moisture axis and any accompanying instability will remain north
of the area, keeping the mostly dry pattern in place across the
state. Showers will favor windward and mauka locations,
particularly through the overnight and morning periods. Despite
stable conditions, some afternoon cloud build-ups and brief
showers can't be ruled out over interior and leeward sections
where localized sea breezes form. Additionally, there could be a
period or two with mostly cloudy skies late Thursday through
Friday due to some high clouds spreading northward over the area.

Breezy trades will return later this weekend and into early next
week as high pressure builds to the north and the aforementioned
moisture axis diminishes.

&&

.AVIATION...
A trough of low pressure north of the state will help keep trades
rather weak to locally moderate over the next few days. Isolated
to scattered showers are forecast to occur along the windward
coasts and slopes, though not expecting anything widespread.
Elsewhere, partly cloudy skies with VFR conditions.

No AIRMETs are currently in effect.

&&

.MARINE...
A front far north of the area has weakened the pressure gradient
over the coastal waters, allowing easterly trade winds to be in
the gentle to moderate range through the end of the week. Breezy
trade wind conditions should return by the weekend as high
pressure builds north of the waters and the aforementioned front
diminishes.

North facing shores will remain tiny today before a moderate
medium period north swell is expected to build Thursday, peak
Thursday night into Friday before declining through the weekend.
Forerunners are expected to hit the offshore buoys late tonight.

Surf along east facing shores will decrease slightly as trades
ease through the rest of the week. Shorelines exposed to the north
swell may see a small bump Thursday evening into Friday. Small
background swells from the south and southwest will keep the surf
from going entirely flat for south facing shores through the week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
None.

&&
$$

DISCUSSION...Gibbs
AVIATION...Thomas
MARINE...Shigesato