Waihee-Waiehu, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

177
FXHW60 PHFO 310225 CCA
AFDHFO

Area Forecast Discussion...CORRECTED
National Weather Service Honolulu HI
425 PM HST Sun Mar 30 2025

.SYNOPSIS...
Rain chances will steadily increase through the week as southerly
winds associated with a cold front and upper disturbance draw
moisture northward into the islands. This front may reach the
islands around Thursday, potentially leading to more widespread
rainfall into next weekend.

&&

.DISCUSSION...
A nearly stationary, deep low pressure system is centered around
1200 miles northwest of Kauai. A jet stream along the eastern
flank of this system will bring cirrus clouds over much of the
state, particularly the western half into Monday. At the surface,
a weak high is located about 2000 miles to the east, with a long
ridge axis that passes just north of Hawaii. Gentle southeast
winds will be the result of the ridge to the east tonight with
land breezes decreasing low clouds over the island interiors
tonight. Vog will carry up from the Big Island to the smaller
islands over the next several days.

The low pressure system and associated cold front will begin to
move closer to the islands Monday and Tuesday. Southerly winds will
strengthen and bring increased moisture initially over the western
end of the state as early as tonight and over the next few days.
Clouds and showers will focus over leeward and south facing slopes
(southeast for Big Island).

Winds will taper off and veer southwesterly as the front nears the
western end of the state allowing land and sea breezes to take
over again. The front may reach Kauai around Thursday and begin to
stall and weaken into Friday with trade winds filling in over the
frontal boundary, potentially leading to more widespread rainfall
into next weekend.


&&

.AVIATION...
Light southeast flow will continue and allow for sea/land breeze
development through tonight. Some isol SHRA and MVFR conds along
interior leeward portions today. VFR conds expected to prevail
through the period.

All locations can expect to see some VOG with the degassing of
Kilauea. It is not impacting vsbys enough to be put into any of the
TAFs but was worth mentioning for general awareness.

No AIRMETs in effect.

&&

.MARINE...
A surface ridge lingering over the region will keep winds light
and variable over the western end of the state and light to
moderate east- southeasterly over the eastern end of the state
through tonight. Deep low pressure and an associated cold front
currently northwest of the state will move east towards the
islands, strengthening winds and shifting them to a more
southerly/southeasterly direction Monday through Tuesday.
Localized terrain enhancement around the Big Island and western
Kauai waters are expected to produce south to southeasterly winds
up to 25 kt. Therefore a small craft advisory has been put into
effect for that time period. The winds are expected to gradually
ease Wednesday and Thursday as the front weakens and its
associated low pressure moves north. Models indicate that the
front will wash out over the western end of the state towards the
end of the week, with with moderate to fresh northeast trades
filling in behind it.

A series of small overlapping north-northeast swells will keep
surf in place along exposed north and east facing shores through
mid week. A small west-northwest swell will bring some small surf
to exposed north and west facing shores Tuesday through Thursday.
A more significant north-northwest swell appears to arrive late in
the week, potentially bringing warning level surf next weekend.

Surf along south facing shores will gradually decrease tonight
through the week and could become choppy with increasing
southerly winds on Monday and Tuesday.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory from noon Monday to 6 PM HST Tuesday for
Kauai Northwest Waters-Kauai Leeward Waters-Big Island Windward
Waters-Big Island Leeward Waters.


&&

$$


DISCUSSION...Foster
AVIATION...Walsh
MARINE...Tsamous