656
FXHW60 PHFO 151324
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
324 AM HST Sat Jun 15 2024

.SYNOPSIS...
Breezy trade wind conditions will persist through next week.
Clouds and showers will predominantly favor windward and mauka
areas overnight into the morning as areas of moisture move
through. An increase in windward shower coverage is possible from
Monday night through midweek due to a mid- to upper-level
disturbance drifting westward across the state. Some of these
showers may briefly extend to the dry leeward areas of the
smaller islands.

&&

.DISCUSSION...
Guidance remains consistent, showing a strong surface ridge north
of the state throughout the upcoming week, possibly strengthening
later on. This will sustain breezy easterly trade winds with
clouds and mostly brief showers favoring windward and mauka
locations. The trade wind inversion will be situated between 6,000
and 7,500 feet, and precipitable water (PW) levels will generally
range from 1.0 to 1.25 inches. Rainfall amounts will likely be
limited, even in windward areas, except possibly during the first
half of the week when an upper-level trough moves westward across
the state, drawing up more moisture.

Guidance indicates PW values increasing above average starting
Monday night through Tuesday in the eastern part of the state, and
later spreading to the western areas by Tuesday night into
midweek. While most showers during this period will favor windward
and mauka areas, some could reach leeward areas, especially
Tuesday night into Wednesday. This pattern of occasional light
showers in our typically dry leeward regions may persist into the
latter part of next week as the pressure gradient tightens,
resulting in brisk easterly trades across the islands.

&&

.AVIATION...
Moderate to locally breezy trade winds will continue. Clouds and
light showers will favor east and northeast facing slopes and
coasts. Isolated spillover showers are expected along leeward
slopes of the smaller islands, especially in the late night and
morning hours.

A weak eddy just west of the Big Island is keeping the leeward
coast and adjacent waters of the Big Island south of Hilo shrouded
in occasional VFR cloudiness. Clouds should lift and dissipate
after sunrise.

AIRMET Sierra remains in effect for mountain obscuration along
windward slopes of the Big Island. Conditions are expected to
improve by late morning. Elsewhere, VFR conditions will prevail
except for brief MVFR CIG or VIS in passing showers.

&&

.MARINE...
A high pressure ridge north of the islands will keep moderate to
strong trade winds blowing across the Hawaii region. A Small
Craft Advisory (SCA) remains in effect for the windier channels
and waters around Maui County and the Big Island through the
weekend. This SCA for the windier waters may continue into much of
next week.

The High Surf Warning (HSW) was extended through this afternoon
as long period south swell heights in the 5 to 6 foot range
continues to show up in this mornings southern offshore buoy
observations. A gradual downward trend is expected starting tonight
to High Surf Advisory levels lasting through Sunday. Only
background small, medium to long period, south to southeast swell
energy will move into the region for the rest of next week.

North shore surf will remain small for the next few days. Small
medium period northwest pulses may provide a tiny bump from Sunday
night into middle of next week. Surf along east shores will
remain small and choppy each day due to continued trade winds.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Warning until 6 PM HST this evening for Niihau-Kauai
Leeward-Waianae Coast-Kahoolawe-Maui Leeward West-Kona-Kauai
South-East Honolulu-Honolulu Metro-Ewa Plain-Molokai Leeward
South-Lanai Leeward-Lanai South-Maui Central Valley South-South
Maui/Upcountry-South Haleakala-Big Island South-Big Island
Southeast.

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

&&
$$

DISCUSSION...Gibbs
AVIATION...Bedal
MARINE...Bohlin