East Honolulu, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

438
FXHW60 PHFO 280104
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
304 PM HST Tue May 27 2025

.SYNOPSIS...
Gentle to moderate trade winds will continue through Thursday as
a weak surface ridge sits about 300 miles north of Kauai. Stable
and rather dry conditions will produce light showers over most
windward slopes, though an upper-level disturbance may produce
more rainfall on Kauai tonight and Wednesday. Trades will
strengthen on Friday and Saturday.

&&

.DISCUSSION...
A gentle to moderate trade winds with stable and rather dry
conditions are in place. A weak surface ridge stalled about 300
miles north of Kauai is driving the trades, which are light enough
for sea breezes to form over sheltered leeward terrain this
afternoon. Precipitable water within the trade wind flow over and
upwind of the islands remains below seasonal normal, and mid-level
ridging is producing a strong inversion based around 6,000 feet.
As a result, rainfall has been limited to well below a tenth of an
inch at nearly all windward gauges, and across leeward areas,
scattered light showers have been confined to the South Kona and
Kau slopes this afternoon.

The subtropical ridge will remain roughly stationary through
Thursday, keeping trades in the gentle to locally moderate range,
and most islands will continue to experience a somewhat dry
conditions with limited rainfall. A shallow low aloft deepening
just north of Kauai tonight may enhance a narrow band of moisture
and produce an increase in shower activity on the Garden Isle
tonight and Wednesday. The upper-level low will also send thin
high clouds over the eastern end of the island chain and produce
strong westerly winds on the high summits of the Big Island,
where a Wind Advisory is in effect through at least Wednesday
afternoon.

Trade winds should strengthen a notch Friday and Saturday as
surface high pressure rebuilds far northeast of the state. The
upper-level low will be pushed off to the east, and ridging aloft
will move overhead, bringing stable and somewhat dry conditions.

Trade winds will become more easterly and may ease slightly Sunday
and Monday due to a surface trough developing several hundred
miles west of the islands. There is the potential for an increase
in shower activity over the western end of the island chain as
well.

&&

.AVIATION...
A drier trade wind pattern continues over the state today giving
way to mostly VFR conditions and a great day for flying.
Overnight, a brief shower over windward locations cannot be ruled
out as an upper-level disturbance is nearby the western part of
the state. However, current radar, satellite, and other
observations continue to indicate that this trend will continue.

There are currently no AIRMETs in effect and none are anticipated
today.

&&

.MARINE...
The ridge far north of the Hawaiian Islands will weaken into
Friday in response to cold fronts passing by to the north. Trade
winds will remain in the gentle to moderate range through Friday,
then increase to fresh levels this weekend as the ridge
strengthens.

Surf heights will remain tiny for most shores through Wednesday.
Surf heights will increase along north and west facing shores
Wednesday night through Thursday as a brief north-northwest
(330-340 deg) swell moves through the region. A larger north-
northwest (330-340 deg) swell will arrive in the islands by early
Saturday morning, producing moderate surf heights along north and
west facing shores, before rapidly declining Saturday night
through Sunday.

A small background pulse of south swell will produce a slight
bump to surf heights along south facing shores starting Wednesday
afternoon, peaking by Friday, then slowly fading through the
weekend.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 6 PM HST Wednesday for Big Island Summits.

&&

$$

DISCUSSION...Wroe
AVIATION...PECHACEK
MARINE...TS