Waihee-Waiehu, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

343
FXHW60 PHFO 291851
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
851 AM HST Mon Jun 29 2026

.SYNOPSIS...
Moderate to locally breezy trade winds will persist into the
upcoming weekend. Bands of low clouds and showers will be at times
be carried in on the trades, focused primarily over windward and
mauka areas during the overnight and early morning hours. One such
band is moving through the islands today and tonight. Additionally,
humidity levels will rise, bringing muggier conditions across the
island chain through the middle of this week.

&&

.SHORT TERM UPDATE...
No major changes to the forecast this morning. The grids and
forecast were updated to reflect the latest NBM for most grids,
and the high resolution model data for the winds in the short
term. In general, PoPs were raised for today and tonight with the
band of moisture moving through. Otherwise minor changes from the
previous forecast.

&&

.PREV DISCUSSION...
Issued at 300 AM HST Mon Jun 29 2026
Currently at the surface, a 1037 mb high is centered around 1650
miles north-northeast of Honolulu, driving moderate trade winds
across the island chain this evening. Infrared satellite imagery
shows mostly cloudy to overcast conditions across much of the
state, with a few leeward areas experiencing less cloud coverage.
Radar imagery shows numerous showers moving into windward slopes
and coasts, with some showers spilling over into leeward
communities at times. Main short term focus revolves around rain
chances.

High pressure will meander well to the north of state during the
next 7 days, keeping moderate, to at times locally breezy, trade
winds solidly in place. Somewhat wetter than normal, summertime
trade wind weather is expected through the period, with showers
favoring windward and mauka areas, particularly during the night
and early morning hours. A couple bands of enhanced moisture will
affect the state this week, bringing an increase in shower
coverage and intensity as they move through. The first batch of
enhanced moisture is already affecting the island chain, and will
continue to do so through the day today, before exiting to the
west of the state tonight. The next area of enhanced moisture is
located around 550 miles east-northeast of the state in the
vicinity of 147W. Portions of this area of enhanced moisture will
begin to affect the islands beginning Tuesday night, and
lingering into early Thursday, increasing shower coverage and
intensity once again.

Both these bands will raise precipitable water values into the
1.5 to 2.0 inch range and elevate inversion heights to between 10
and 12 kft. Some locally heavy rainfall can`t be ruled out as
these bands of moisture move through, particularly the second
batch of moisture affecting the islands during the middle of the
week. That said, with the trades in place, a widespread flash
flood threat is not expected, but some minor flooding could very
well necessitate flood advisories over windward and mauka areas
during this time. Additionally, dewpoints are forecast to increase
to around 70 or the lower 70s today through the middle of the
week, making it feel more muggy across the island chain.

&&

.AVIATION...
Low clouds and scattered showers associated with a dissipated
trough will push through the island chain today. Breezy trade
winds will focus showers across windward sides, with a few showers
reaching leeward sides of the smaller islands.

AIRMET Sierra remains in effect for tempo mountain obscuration
above 2000 feet for windward sides of Kauai, Oahu, Molokai, Maui
and Big Island due to these showers. Expecting this AIRMET to
remain in effect at least through early afternoon, and potentially
the rest of today, until this moisture moves west of the area.

AIRMET Tango is also posted for tempo moderate leeward turbulence
below 8000 feet for all islands due to the breezy trade winds.
Expect this AIRMET to continue at least for the next couple of
days.


&&

.MARINE...
An area of surface high pressure will remain centered well north
of the Hawaiian Islands this week and help drive moderate to fresh
trades trades across the region. The Small Craft Advisory (SCA)
will continue through this afternoon for much of the waters around
Maui County and Big Island, as well as the Kaiwi Channel. The SCA
will then be trimmed back to the typical windy waters around Maui
County and the Big Island by this evening as trades ease slightly
into Tuesday.

The current moderate, long-period south swell will maintain today,
then gradually decline through midweek, leading to a decreasing trend
in south and west shore surf through Wednesday. A small bump in south
shore surf is possible Thursday into Friday with the arrival of a
small, long-period south swell, but another larger long-period south
swell energy pulse should arrive by late Saturday.

Surf along east-facing shores will remain rough and choppy through
the week with moderate to fresh trades in place. Nearly flat surf
heights will persist along north facing shores.


&&

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

Small Craft Advisory until 6 PM HST Tuesday for Alenuihaha
Channel-Big Island Leeward Waters-Big Island Southeast Waters-
Maalaea Bay-Pailolo Channel.


&&

$$

DISCUSSION...Jelsema
AVIATION...Foster
MARINE...Quesada
SHORT TERM UPDATE...M Ballard