985
FXHW60 PHFO 201904
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
904 AM HST Thu Aug 20 2026

.SYNOPSIS...
Trades remain weak through Friday as a trough advances north of
the islands. Tropical Depression 2C has formed southeast of Hawaii
and is forecast to track south of the area early next week
bringing strengthening winds and potential for heavy rainfall,
especially to the eastern end of the state.


&&

.SHORT TERM UPDATE...

Surface troughing associated with tropical remnants positioned
immediately north of the Hawaiian islands will advance NW during
the next 24 hours. This will substantially weaken the gradient
leading to very light winds, expanding sea breezes, and muggy
weather with dewpoints in the low 70s. A few afternoon showers
over leeward areas will be possible today and tomorrow with light
trades delivering limited showers windward overnight. Bumped pops
downward accordingly to highlight relatively dry weather for this
period. Benign trade wind weather then prevails into Saturday,
though trades likely undergo strengthening becoming breezy to
locally strong during this time as TD 2C gradually lifts out of
the deep tropics and advances WNW or NW during the weekend. Will
reserve additional commentary on this system until the afternoon
package.


&&

.PREV DISCUSSION...
Issued at 508 AM HST Thu Aug 20 2026

Weak trade winds today will allow for a sea breeze to develop,
increasing chances of showers in some leeward areas. Winds will
increase late Friday and veer easterly. Typical trade showers will
return over windward and mauka areas, most common at night. Forecast
for Saturday will be influenced by how the tropical system to the
east-southeast of the state evolves. Current forecast maintains
typical trade wind showers and increasing winds.

Tropical Depression Two-C has developed 960 miles east-southeast of
Hilo. The first look at the potential track keeps the storm south of
the Big Island, but it is still early in the forecast process and
the track could shift either north or south in coming advisory
cycles. Impacts from rain, wind, and surf can be experienced well
outside the center of the storm so do not focus too much on the
exact track. Current guidance indicates that precipitation will
increase on the east side of the state Saturday night into Sunday,
spreading west Sunday night into Monday. The timing, direction, and
magnitude of the strongest winds remain highly dependent on the
track and intensity of the system.

In anticipation of critical new updates with each of the advisory
packages issued by the National Hurricane Center (NHC), NWS Honolulu
will delay the issuances of our typical forecast package products
(AFD, SFT, PFM, ZFP, SRF, CWF, etc) until after the release of NHC`s
suite of products, to incorporate the latest and most up-to-date
information on Tropical Depression Two-C.

&&

.AVIATION...
A surface trough moving from east to west through the islands
today will keep winds light enough for local land and sea breezes
to set up. Afternoon clouds and showers are expected over the
interior of the islands, with some MVFR conditions possible. Some
clearing of the clouds and showers are expected overnight. However
with weak trade wind flow setting up behind the trough, some
clouds and showers will set up over windward and mauka areas. VFR
conditions are expected to prevail, except those pockets of MVFR
in clouds and showers.

No AIRMETs are currently in effect, and none are expected through
Friday night.


&&

.MARINE...

A trough just northeast of the islands will track northwestward
across the offshore waters, leading to a period of light and
variable winds for most waters today. By late Friday, moderate to
locally fresh trades will begin to build back into the region as
the trough exits to the northwest, high pressure drifts southward
closer to the island chain, and Tropical Depression Two-C nears
the state from the southeast. The forecast for this weekend will
depend significantly on the uncertain track of this tropical
cyclone.

Surf along south facing shores will remain slightly below average
through Thursday. A long period south-southwest swell generated
from gales just south and east of New Zealand will begin arriving
later today into Friday, boosting surf to near or slightly below
average by Saturday. Surf along east facing shores also remains
below average with weak trades, then builds this weekend as the
trades restrengthen. Surf along east- and south-facing shores
will be compounded by a southeast swell generated by Tropical
Depression Two-C that will build through Sunday and may persist
through early next week. This short-period tropical swell could
cause surf to approach advisory levels along east facing shores of
the Big Island Saturday night into Sunday. North facing shores
will remain tiny through Friday, with a slight bump from Lala
swell possible this weekend.


&&

.FIRE WEATHER...
Issued at 508 AM HST Thu Aug 20 2026

Trade winds will weaken today, increasing chances of showers for
the leeward side of the islands. Trade winds increase over the
weekend with showers switching to windward. The inversion is 6000
to 7000 ft. Increased wind and rain possible across the state late
in the weekend into early next week.

&&

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

&&

$$

SHORT TERM UPDATE...JVC
DISCUSSION...CO
AVIATION...Walsh
MARINE...Farris
FIRE WEATHER...CO