Area Forecast Discussion for Hawaii

Area Forecast Discussion   Issued: 04/16/2026 05:55:00 AM UTC

                        
915
FXHW60 PHFO 151955
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
955 AM HST Wed Apr 15 2026

.SYNOPSIS...
A low pressure system lingers far north of the Hawaiian Islands
producing light and variable winds with chances for showers into
Thursday. A passing high pressure system will bring a short return
to easterly trade winds with subtle drying trends from Thursday
night into Saturday. A series of low pressure systems passing just
north of the state will produce light southeasterly winds from
Sunday into the middle of next week.

&&

.SHORT TERM UPDATE...
Issued at 933 AM HST Wed Apr 15 2026

Forecast remains on track with minimal updates needed this
morning. Mid and high clouds continue to stream over the islands
this morning (especially the western half of the state), with
light and intermittent shower activity. Relatively light winds
will continue into tomorrow, allowing for daytime sea breezes and
overnight land breezes.

&&

.PREV DISCUSSION...
Looking into the big picture satellite imagery this morning, we
see a low pressure system far north of the Hawaiian Islands,
along with high and middle clouds drifting across the state
associated with divergence under a Sub Tropical Jet stream in the
upper levels of the atmosphere. These cloudy skies will linger
into early next week with chances for light to moderate showers
each day.

The low pressure system currently north of the islands will keep
lighter large scale winds in the forecast into Thursday. This
means local scale island day time heating will drive onshore sea
breezes into all islands, building clouds and brief shower trends
over island mountains and interior sections peaking during the
afternoon hours.

A passing high pressure system north of the state from Thursday
night into Saturday will briefly build in easterly trade winds
across the region. Wind speeds will become strong enough to limit
sea breezes to terrain sheltered leeward western slopes of each
island. Subtle drying trends will develop during this time period
due to a slight increase in subsidence, downward vertical motions
creating warming and drying effects, making the atmosphere a bit
more stable.

However, the return to easterly trade winds will be fleeting and
vanish quickly by Sunday as a series of low pressure system
develop and slowly track north of the state. These passing lows
appear to track far enough north to limit any heavy rainfall or
flooding issues for the islands. A weak ridge will settle in over
the islands producing a stable southeasterly wind across the
region. Any enhanced showers in this wind driven pattern will
favor southeast slopes of Maui and the Big Island with modest
additional rainfall amounts. Elsewhere rainfall will be limited as
the passing cloud bands will move more parallel to island
mountains and the Big Island will produce a leeside rain shadow
across much of the islands in Maui County.

&&

.AVIATION...
Issued at 933 AM HST Wed Apr 15 2026

Mostly VFR through Thursday. Midlevel precipitation was moving
northeast across the area this morning, but is not expected to
create significant MVFR conditions. Generally light southeast winds
today will become more easterly overnight and Thursday as trades
return.

No AIRMETs in effect, and none are expected.

&&

.MARINE...
Issued at 933 AM HST Wed Apr 15 2026

Troughing to the west maintains gentle to locally moderate ESE
winds through Thursday. The strongest breezes will occur through
the typical windy channels surrounding Maui and the Big Island.
Building high pressure then supports moderate to locally fresh
trades across the waters into the weekend. A small, short-
period, NW swell diminishes into Thursday and remains subdued
through the weekend. A small, medium-period, S swell will boost
surf along S shores through Friday then lower over the weekend.
Surf along E shores remains below the seasonal average as trades
remain light. However, increasing trades by week`s end should
brings a slight bump to surf. Low pressure advancing S along the W
coast of the US next week sends a small, medium period NE swell
toward the islands by midweek.

&&

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

&&

$$

SHORT TERM UPDATE...Vaughan
DISCUSSION...Bohlin
AVIATION...Parker
MARINE...JVC