Area Forecast Discussion for Hawaii

Area Forecast Discussion   Issued: 05/07/2026 05:11:00 PM UTC

                        
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FXHW60 PHFO 070711
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
911 PM HST Wed May 6 2026

.UPDATE...
Quiet evening for the islands under partially cloudy skies and
light breezes. Resident moisture is near to slightly below normal
by early May standards with weak troughing northeast of the state
providing just enough large scale forcing to suggest the
occasional shower passing through within light northerlies. The
state lies in a col, or a height weakness region, between two
surface highs far northwest and northeast of the island chain.
This translates to a slack surface pressure gradient through
tonight whereas localized drainage or land breezes will be the
dominant wind. The presence of this vicinity northeast surface
trough, with approaching weak mid to upper level troughing from
the northwest within a somewhat moistened environment, will ensure
thickened mauka clouds and more frequent light precipitation
within higher elevation. Tomorrow will be another partly cloudy
day with thicker clouds and more frequent showers being confined
to windward upslope regions and higher terrain. While feeling a
touch more humid due to the lack of moderate trades, thicker cloud
cover should keep many communities in the mid to upper 70s for
the majority of the afternoon. High pressure to the northwest will
move across to the north the next couple of days. This will assist
in tightening up the pressure gradient over the islands and
strengthening trade winds. Trades will gradually make their return
tomorrow and strengthen to more moderate magnitudes this weekend.

&&

.SYNOPSIS...
The light winds and humid conditions we have had (due to a weak
surface trough) will end tonight. Interior clouds and a few
showers will continue into the evening hours, followed by partial
clearing overnight. Light trade winds will return Thursday into
Friday, bringing a more typical pattern of mainly windward and
mauka showers with a few afternoon showers spilling over into
leeward areas. A slight increase in shower coverage remains
possible Friday night through Saturday night. Stronger trade winds
and more stable conditions arrive early next week.

&&

.PREV DISCUSSION.../ISSUED 343 PM HST Wed May 6 2026/

Skies were mostly cloudy across the state this afternoon, with
only a few exceptions. Radar shows isolated showers, mainly over
south central Oahu and northeast Molokai. Winds were on the
lighter side as trades are just starting to build back into the
region. North to northeast winds were seen across Kauai, Oahu, and
Maui County, with variable winds on the Big Island.

A weak surface trough has moved through most of the state was
centered over the Big Island this afternoon, and will make it
past the Big Island this evening. This will allow trades to build
in across the entire state tonight and on into Thursday.
Initially, wind speeds will be light to moderate, but stronger
winds will arrive this weekend (most likely Saturday night into
Sunday). Once this increase arrives, winds should be moderate to
breezy well into next week.

The return of the trades will also bring back the typical pattern
of mainly windward and mauka showers, occasionally reaching
leeward areas. PW values will generally be around an inch, which
means that heavy rain is unlikely. There will be a short-lived
exception from Friday night into Saturday night when values are
forecast to rise to around 1.3 inches. This increase is due to the
combination of a weak upper level trough and a band of low-level
moisture. During this period, there is an increased chance of
brief moderate to heavy rain.

Long range models show the possibility of even stronger trades
developing late next week and beyond, but we will need to get
closer in time before we can have reasonable confidence in this
solution.

&&

AVIATION...
Light to moderate trades gradually build back across the area
tonight into tomorrow, allowing for leeward areas to experience a
mix of land breezes that will help to clear out clouds and shower
activity. VFR conditions will continue to generally prevail with
except for remnant showers over island interiors. AIRMET Sierra
remains in effect for portions of Kauai, Oahu, and Molokai through
the late evening to account for these clouds and showers.

&&

MARINE...
A trough north of the central islands will allow for weak to flow
to continue across all local waters tonight. Thursday into
Friday, a surface ridge building northwest of the state will bring
a return of light to locally moderate northeasterly trades.
Trades will then strengthen into moderate to locally fresh range
by this weekend as the ridge continues slowly to build north of
the islands. A Small Craft Advisory may be needed for the typical
windy waters surrounding Maui and the Big Island by late Saturday
into Sunday.

Forerunners from the next long period northwest swell had arrived
at offshore buoy 51001 a little after 3 PM this afternoon. Thus,
expecting the swell to show up at Hanalei buoy momentarily. As
this swell fills in later tonight into Thursday, surf heights
along north and west facing beaches will become elevated and rise
to just shy of advisory levels. The forecast is also complicated
by the arrival of another moderate period northwest swell tonight.
Surf will then gradually decline over the weekend into early next
week.

A small, long-period south swell, generated from a storm-force
low that tracked southeast of New Zealand last week, will fill in
tonight and likely provide a small bump in south shore surf
through the end of the week.

Surf along east facing shores will remain below normal during the
next several days due to the lack of strong trades over and
upstream of the islands. East shore surf will gradually increase into
the weekend as trades make a slow return.

&&

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

&&

$$


UPDATE...Blood
DISCUSSION...Parker
AVIATION...Pierce
MARINE...Thomas