992
FXHW60 PHFO 021325
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
325 AM HST Tue Jul 2 2024

.SYNOPSIS...
A broad high pressure ridge will remain locked in place north of
the Hawaiian Islands into the upcoming weekend. Trade wind speeds
will range from moderate to breezy for most days with slight
decreasing wind speed trends from Thursday onward. Fairly stable
conditions will produce mostly brief passing showers over windward
and mountain areas.

&&

.DISCUSSION...
A broad subtropical ridge north of the island chain will keep
moderate to breezy trade winds in the forecast lasting into the
middle of the week with slight decreasing wind speed trends from
Thursday onward. A slight ripple in the force is shown on infrared
satellite imagery this evening as a band of clouds continues to
move into the Big Island. This north to south oriented cloud band
is associated with a weak low level trough riding into the islands
on the easterly trade winds. Expect a slight increase in clouds
and showers through the early morning hours across the windward
slopes of Molokai, Maui and the Big Island, and then slightly
increasing shower activity over windward Oahu and Kauai later
tonight; as these unsettled clouds drift into the mountains of
each island. A few high level cirrus ice crystal clouds are
drifting over the state for the next few days, enhancing island
sunrise and sunset colors.

Otherwise mostly dry conditions will prevail this week with only
brief passing showers over windward and mountain areas. Shower
amounts will be limited due to the strong subsidence under this
high pressure ridge pattern. Trade wind thermal inversion heights
will range from around 4,000 to 6,500 feet with most windward
areas only seeing isolated to scattered shower coverage, favoring
the overnight to early morning hours. Some exceptions may include
the eastern slopes of Maui, and the windward and Kona slopes of
the Big Island where periods of passing rain showers will likely
continue.

&&

.AVIATION...
Moderate to locally breezy trade winds will continue through
tonight. A band of low clouds and showers will move from east to
west across the state today, bringing some MVFR cigs/vsbys to
windward areas as it moves through. Conditions will improve behind
the band of clouds and showers, although some showery weather may
linger across Kauai through the evening hours.

AIRMET Sierra is in effect for mountain obscuration across
windwardsections of Molokai, Maui and the Big Island. The AIRMET
will likely need to be expanded to include Oahu later this
morning.

&&

.MARINE...
High pressure north northeast of the state will bring fresh to
strong trades through most of the week. By this weekend, the high
will weaken and move off to the northeast as a trough approaches
from the west and allow for trades to ease slightly across the
local waters. A Small Craft Advisory has been extended through
Thursday morning for the waters and channels around the Maui and
The Big Island. Expect conditions in these typical windy areas to
remain at or slightly below advisory levels Thursday afternoon
into Friday.

No significant south swells are expected during the forecast
period. However, a series of small south-southwest and southeast
swells will keep south facing shores from going flat.

Flat to tiny surf conditions will continue along north and west
facing shores through most of the week. East shore surf will be
close to seasonal levels through late this week, as fresh to
strong east northeast trades persist over and upstream of the
islands. A fetch of strong northeast winds well off the California
coast should bring a small, medium period, northeast swell
Saturday into early next week. Some of this swell should wrap into
select north facing exposures as well.

Water levels running roughly 0.5 ft higher than normal around the
Big Island combined with the new moon tides could cause minor
flooding issues between July 2nd and July 6th with peak water
levels expected on July 4th. Our last full moon, we did receive
reports of some areas of the coastline becoming inundated with the
high tide such as Coconut Island and Puhi Bay. A Coastal Flood
Statement will likely be needed for the Big Island near the 4th of
July. For the other islands, water levels are running just a
touch above normal and will likely not reach our criteria of 1
foot above the Mean Higher High Water (MHHW).

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 AM HST Thursday for the windier areas
around Maui and the Big Island.

&&

$$

DISCUSSION...Bohlin
AVIATION...Jelsema
MARINE...JT