735
FXHW60 PHFO 170610
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
810 PM HST Tue Jun 16 2026

.SYNOPSIS...

Lighter background winds will support daytime sea breezes and
nighttime land breezes from Wednesday through Friday. Thus, most
cloud cover and shower activity will favor interior and mountain
areas during the afternoons. In addition, deeper moisture
associated with a weak trough will move northward from the
southeast Wednesday through Friday, and will briefly increase
shower chances island-by-island as it weakens. A more typical
trade wind pattern will return late this weekend.

&&

.SHORT TERM UPDATE...

PoP adjustment were made to account for current trends. Previous
forecat is otherwise on track.

&&

.PREV DISCUSSION...
Issued at 356 PM HST Tue Jun 16 2026

This afternoon, mostly dry and stable conditions are prevailing
across the main Hawaiian Islands. Latest satellite and radar
imagery shows isolated light showers across the region, and
statewide rain gauge networks have largely reported little to no
rain today. The exception is over Kauai and Niihau, where showers
have been slightly more persistent than elsewhere in the state. A
late morning advanced scatterometer pass, as well as surface
observations, show that moderate trade winds are prevailing.

As a series of fronts move across the North Pacific well north of
the island chain, moderate trade wind flow will become disrupted,
further weakening winds across the region. Daytime heating,
combined with weak background surface flow, will lead to daytime
sea breezes and nighttime land breezes for the next few days.
Clouds and showers should mainly be limited to over the island
interiors and mountainous terrain, particularly during the day.
The one caveat in the forecast, however, is that a weak surface
trough is currently located southeast of the Big Island. Latest
hi-res guidance and global models depict this weakening feature to
move northward in the vicinity of the eastern end of the state on
Wednesday. As a result, shower activity will likely increase over
the Big Island tomorrow, especially compared to what was
experienced today. This trough will continue lifting north, and is
progged to be located just east of Maui by Wednesday evening. As
the trough moves northward, expect increased showers for portions
of Maui County late Wednesday into Thursday, and possibly for Oahu
as well by Thursday afternoon. The weakened feature will then
continue to dissipate as it moves away from the state.

After a brief period of east-southeasterly flow Saturday, moderate
easterly trades will return during the second half of the
weekend. Fairly dry conditions will limit windward shower
coverage into early next week.

&&

.AVIATION...

Moderate trade winds continue through the evening before
weakening tomorrow. A surface trough SE of the Big Island will
progress northward, bringing enhanced shower activity to windward
sections of the Big Island and possibly Maui tomorrow morning.
Cloud and shower development is possible across leeward areas of
the state as well tomorrow afternoon. Expect MVFR conditions
within showers, and brief IFR conditions within heavier showers.

No AIRMETS are currently in effect, however Sierra may be needed
as cloud and shower coverage expands with the aforementioned
system moving in.


&&

.MARINE...
Issued at 356 PM HST Tue Jun 16 2026

A ridge of high pressure north of the state is driving moderate
to locally fresh trades. Trades will ease to light to moderate
speeds Wednesday as the trough pushes the ridge east of the state.
The ridge will strengthen north of the area over weekend as the
trough weakens and lifts far north, allowing moderate to fresh
trades to return.

The large, long period south southwest swell that brought warning
level surf to the state earlier this week will continue to slowly
decline. A High Surf Advisory (HSA) remains in effect through
tonight for all south facing shores. Surf heights are expected to
drop below advisory levels by Wednesday. Another moderate, long
period, south southwest swell is expected to fill in Wednesday
night into Thursday that could push surf back up to HSA levels
along south facing shores. This swell will slowly fade Friday
through the weekend.

Surf along north facing shores will remain flat to tiny through
the forecast period. Surf along east facing shores will remain
below average as easterly trade winds ease through the end of the
week.

The Coastal Flood Statement has been extended through tonight for
minor coastal flooding of vulnerable low-lying coastal roadways,
docks, boat ramps and other coastal infrastructure due to King
Tides. King Tides combined with water levels that are running
higher than predicted will lead to minor flooding potential around
the daily peak tide, which will be during the late afternoon and
early evening hours. While minor coastal flooding is expected
along all shorelines, the combination of the large south southwest
swell and peak daily high tides will make low- lying coastal
areas along south and west shores susceptible to more widespread
coastal flooding through this evening.

A Marine Weather Statement has also been extended through tonight due
to the moderate-to-long, long-period south southwest swell
producing harbor surges and breaking waves near harbor entrances
along south and west- facing harbors.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory until 6 AM HST Wednesday for Big Island South-
Big Island Southeast-East Honolulu-Ewa Plain-Honolulu Metro-
Kahoolawe-Kauai South-Kauai Southwest-Kipahulu-Kohala-Kona-Lanai
Leeward-Lanai South-Maui Central Valley South-Maui Leeward West-
Molokai Leeward South-Molokai Southeast-Niihau-South Haleakala-
South Maui/Upcountry-Waianae Coast.


&&

$$

UPDATE...Walsh
DISCUSSION...Vaughan
AVIATION...Evans
MARINE...Almanza

NWS HFO Office Area Forecast Discussion