423
FXHW60 PHFO 230145
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
345 PM HST Sat Jun 22 2024

.SYNOPSIS...
High pressure far north of the islands will maintain breezy trade
winds through early next week. Passing showers will favor windward
and mauka areas. Trades weaken slightly towards the middle of
next week, with an uptick in showers possible late next week.

&&

.DISCUSSION...
Breezy trade winds continue this afternoon as the 1030 mb surface
high remains approximately 825 mile north of the state. Meanwhile,
stable conditions continue across the islands as a mid-level ridge
remains in place over the region. Radar and satellite imagery show
passing scattered showers over windward and mauka areas early this
afternoon across the smaller islands. Wetter conditions continue
across Windward Big Island this afternoon and will likely persist
into this evening. Isolated showers over the Kona slopes of the
Big Island will also continue through this evening.

Guidance continues to show the strong surface high anchored north
of the state through Monday which will maintain our breezy trade
wind conditions. A stable and rather typical summertime rainfall
pattern will prevail, leading to modest rainfall over windward
slopes. Aside from some brief afternoon showers over Kona slopes
of the Big Island, leeward areas will be mostly dry.

Trades look to then weaken slightly to moderate strength towards
the middle of next week as the high to our north finally weakens.
An uptick in showers looks possible late next week as an upper-
level disturbance approaches the region.

&&

.AVIATION...
Breezy to locally windy trades will continue through Monday.
Showery cloud bands embedded within trade flow will produce
periods of MVFR conditions across windward areas of each island
at night and through the morning hours each day. Each afternoon
will be clearer and drier.

AIRMET Sierra remains in effect for tempo mountain obscuration
for north and east slopes of Kauai, Oahu, Molokai, and Maui.
The eastern slopes of the Big Island are also included in this
AIRMET, which may need to be adjusted as cloud cover changes
through each day.

AIRMET Tango remains in effect for mod low level turb over and
downwind of island terrain due to the breezy trade winds. This
AIRMET will likely continue through Monday.

&&

.MARINE...
Strong easterly trades will continue into early next week,
supporting the Small Craft Advisory in place for all waters. Seas
will remain rough, with heights hovering around and just under
the advisory level over exposed waters. Guidance shows a slight
downward trend Tuesday through midweek due to the surface ridge
potentially weakening to the north.

Surf along east-facing shores will remain rough through early
next week due to the aforementioned strong trades locally and
upstream of the state. A gradual downward trend is possible
Tuesday through midweek.

Surf along south-facing shores will continue to trend up this
weekend as a small south swell moves through. This should be
short-lived, with a downward trend expected early next week.
Despite a blocking high that has set up over our typical swell
window near/southeast of New Zealand, a gale has formed to its
northeast with the head of the fetch aimed at the islands within
the 180 to 200-degree directional band. Given the shorter travel
distance, surf associated with this source should trend up late
next week.

Surf along north-facing shores could trend up above flat levels
early next week due to a small, medium-period northwest swell from
a marginal gale lifting northeastward near the Aleutians. On its
heels is a compact storm-force low, currently several hundred
nautical miles east of Japan, that could send a similar northwest
swell through the area late next week.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST Monday for all Hawaiian
waters-

&&

$$

DISCUSSION...Ahue
AVIATION...Powell
MARINE...JVC