719
FXHW60 PHFO 022006
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
1006 AM HST Wed Apr 2 2025

.SYNOPSIS...
A frontal boundary will move over Kauai Wednesday night into
Thursday and stall and dissipate around Oahu Thursday into Friday.
This will bring an increase of wet weather over the western half
of the state especially over Kauai. Breezy to locally strong
trade winds should return on Friday. A showery trade wind pattern
will continue to persist over Kauai through the weekend due to
lingering moisture.

&&

.DISCUSSION...
A frontal boundary currently located west of Kauai will gradually
weaken as it slowly shifts eastward through Thursday. Satellite
imagery this morning is showing a broad NE to SW oriented line of
showers and thunderstorms roughly 150 to 200 miles west of Kauai.
This line of heavier showers is expected to weaken some as it
moves over Kauai Wednesday night into Thursday. For today, we will
continue to see showers develop ahead of the front and we will
also see sea breezes develop. Daytime sea breezes should allow for
afternoon cloud build ups over interior and mountain areas. Any
showers this afternoon should generally drift northward or
northeastward due to the southerly flow today. Rainfall amounts
should remain light to moderate due to the lack of instability
aloft and moisture levels remaining near normal.

Late Wednesday night into Thursday, the frontal boundary should
reach Kauai and will bring the threat for heavier showers. The
greatest rainfall is expected to be over the northern half of
Kauai and showery weather is expected to persist from Thursday
through Friday with frequent showers. With precipitable water
values of around 1.8 inches and some marginal instability aloft
from the upper level trough, some minor flooding impacts will be
possible across Kauai. For Oahu, showers will not be as widespread
as Kauai, but some brief downpours should be expected on Thursday
especially in the afternoon and evening hours. For rest of the
state, sea breezes will allow for afternoon cloud build ups once
again with some scattered showers over interior and mountain areas
during the afternoon.

The frontal boundary is expected to weaken and stall somewhere
around Oahu on Friday. Breezy to locally strong trade winds will
also return on Friday with our typical trade wind pattern
returning across most of the state. The one exception is over
Kauai, where lingering moisture will continue to produce showery
weather through the weekend.


&&

.AVIATION...
Moderate southerly winds will continue over the western half of
the state as a cold front slowly approaches from the northwest.
Expect an uptick in shower activity across Kauai and Oahu as
moisture streams in from the south ahead of the front, with periods
of MVFR likely within the heavier showers. The eastern half of
the state will see moderate to locally breezy southeasterly winds
continue, with localized sea breezes in sheltered areas. Conditions
should remain mostly VFR. Winds are expected to decrease through
the day, statewide, becoming light and variable overnight.

No AIRMETs are currently in effect.

All areas will continue to see some Vog due to the ongoing eruption
of Kilauea. However, Vog is not expected to impact visibilities
enough to warrant a mention in any TAF.

&&

.MARINE...
A cold front, slowly approaching the islands from the west, will
maintain breezy southeasterly flow across the eastern portion of
the state and light to moderate southerly flow elsewhere. Instability
aloft, ahead of the front, will lead to isolated thunderstorms
west of Kauai later today. A Small Craft Advisory (SCA) remains in
effect for waters around the Big Island for local wind
acceleration around and along the parallel coastlines to the wind
direction. The front should move across Oahu and Kauai Friday and
then dissipate by this weekend. Expect moderate to locally strong
northeast trades to return this weekend and persist into early
next week.

A small west- northwest swell will maintain small surf along
north and west facing shores today and Thursday. A moderate north-
northwest (330-350) swell is expected to arrive on Friday and
could produce advisory level surf. A large to extra large, long
period, north to north- north west (340-360) swell is forecast to
build this weekend and would likely produce warning level surf
along north facing shores with advisory level surf across west and
east facing shores. This swell, aside from being hazardous to
small craft, could generate harbor surges along north facing bays
and inlets.

Surf along south facing shores will remain low through this
weekend with mainly background energy dominating.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST this evening for Big Island
Windward Waters-Big Island Leeward Waters.


&&

$$


DISCUSSION...Kino
AVIATION...TS
MARINE...Bedal