Waipio, Hawaii 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

994
FXHW60 PHFO 231900
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
900 AM HST Tue Jun 23 2026

.SYNOPSIS...
Moderate to locally breezy trade winds expected through the rest
of the week. An increase in moisture is expected through Wednesday
causing showers to increase along windward and mauka locations.
Some limited spillover is possible over to leeward areas. Some
drier conditions move in for the weekend.

&&

.SHORT TERM UPDATE...
Radar shows numerous light showers moving east to west over most
windward and many mauka areas this morning. Skies were mostly
cloudy in those same areas, with a few mostly sunny spots in
leeward areas. Trade winds will increase today through tonight,
leading to additional windward and mauka showers. This is all
handled well by the current forecast and no changes are
anticipated this morning.

&&

.PREV DISCUSSION...
Issued at 319 AM HST Tue Jun 23 2026

Looking at current satellite and radar imagery this morning,
scattered showers and low clouds are moving across the island
chain. Some showers are making it over into leeward areas. These
showers are caused by a surface trough moving in from the east.
Expect and increase in showers to continue into Wednesday.

A weak upper level low to our northeast will drift southwest and
come near the state Wednesday into Wednesday night before moving
off to the northwest and then weakening through Sunday. This upper
low will bring cooler air aloft, slightly enhancing instability
through the rest of the week. This will lead to a deeper surface
boundary and higher inversion height. A slight uptick in rain
rates is possible along windward and mauka locations but don`t
expect widespread heavy or flooding rains.

North of our weak upper level low, an upper level ridge will help
keep a strong surface high positioned to our northeast, off the
coast of the mainland. This will keep the trades blowing at
moderate to occasionally breezy levels into the weekend. Models
indicate some drier air approaching Friday and Saturday, reducing
the number and strength of showers.

&&

.AVIATION...
Moderate to locally breezy trade winds expected through midweek.
A trough is moving up the island chain from the east and will
continue its trajectory through Wednesday. Expect an increase in
SHRA and low cigs causing MVFR conds.

AIRMET Sierra is in effect for mtn obsc across N - SE sections of
Oahu, Molokai, Lanai, and Maui. Expect these conditions to
continue through today. The AIRMET may be expanded to include
Kauai and Big Island later today as well.

&&

.MARINE...
The subtropical ridge will strengthen north of the islands through
Wednesday, increasing trade wind speeds to Small Craft Advisory
(SCA) thresholds from Wednesday morning on into the weekend
across the windier waters and channels near Maui and the Big
Island. A low level trough passing from east to west across
Hawaiian Coastal and Offshore waters from Tuesday into Wednesday
along with an upper level disturbance will enhance rain shower
activity for all waters.

A series of small to moderate, medium to long period south swells
will keep surf along south facing shores elevated through the week.
A moderate, medium period south swell will slowly fade through
Wednesday. The forerunners of the next long period south swell
will begin to arrive in the islands by Wednesday morning, and then
build into Wednesday night, peaking on Thursday with head high to
overhead surf heights at most exposed south shore surf breaks.

Surf along east facing shores will gradually build through
Wednesday and then hold into the weekend as trade winds
strengthen. West facing shores will remain on the small side with
a slight south swell wrap. Surf heights along north facing shores
will remain fairly flat due to the lack of significant north
swell energy.

&&

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

&&

$$

SHORT TERM UPDATE...Parker
DISCUSSION...Walsh
AVIATION...DT
MARINE...Quesada