882
FXHW60 PHFO 051353
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
353 AM HST Fri Jul 5 2024

.SYNOPSIS...
Moderate trade winds and a stable pattern of mainly light
windward showers will prevail through Monday. Increasing trade
winds and slightly wetter conditions are possible around the
middle of next week, with breezy trades continuing into the
weekend.

&&

.DISCUSSION...
A broad surface ridge far north of the islands continues to
drive moderate trade wind flow, while a deep mid- to upper-level
ridge parked overhead maintains very stable conditions with
inversions at Lihue and Hilo based at 5000 and 6500 ft,respectively.
After the passage of a short-lived low-level dry slot overnight,
another batch of moisture is moving in with windward showers on
the increase early this morning, especially over and upstream of
Oahu. However, the stable airmass will keep rainfall amounts on
the modest side.

This stable, summertime trade wind weather pattern will dominate
into early next week with only minor fluctuations in moisture
levels and wind speeds. The surface ridge north of the state will
weaken slightly tonight and Friday, leading to a small decline in
winds through the weekend. The ridge aloft will remain anchored
over the region, keeping stable conditions in place and a temperature
inversion fluctuating between 5000 to 8000 feet. Precipitable water
will be generally below the seasonal average, so rainfall will
remain modest and windward-focused. Aside from a few afternoon
showers on the Kona slopes of the Big Island, leeward areas will
be rather dry.

No big changes to the overall pattern are noted through the
second half of next week. Trades look to increase to breezy levels
around Monday night or Tuesday as the ridge to the north strengthens.
Stable conditions will persist, but the GFS and ECMWF are hinting
at a possible modest increase in windward showers around Tuesday.

&&

.AVIATION...
Moderate to locally breezy trades will continue through the next
couple of days. SHRA and brief MVFR conds will generally be
confined to windward and mauka locations, but a few SHRA may make
it over to leeward areas. Otherwise VFR conds should prevail.

AIRMET Sierra is in effect for mtn obsc for Oahu, Molokai and Maui
as several bands of SHRA move into the islands. Conds should
improve later this morning.

&&

.MARINE...
The pressure gradient over the local waters will remain weak the
next several days in response to lower pressure over the eastern
Pacific. High pressure will better establish itself northeast of
the state, re-tightening the upstream pressure gradient, and this
will restrengthen winds by the middle of next week. Trades holding
at their current moderate speeds will maintain 4 to 6 foot sea
heights through early next week.

No significant swells are expected from any direction for the
remainder of the week. A series of small, medium period south
southeast swells will produce fun south-facing shore waist to
chest high surf. A recent small fetch of strong northeast winds
off the U.S. Pacific Northwest coast has generated a small, medium
period northeast swell. This swell is scheduled to arrive Sunday
and reinforce the resident short period wind wave swell. Some of
this northeast swell will wrap into more northern exposures.

Higher than normal water levels, in tandem with new moon tides,
has increased water levels around Big Island and Maui County.
Peak water levels of between 3.0 to 3.5 feet above Mean Lower Low
Water (MLLW) are expected during periods of high tides. This will
continue to create minor coastal flooding issues through the
weekend. A Coastal Flood Statement highlighting this flooding
threat remains in effect for both Big Island and Maui County.

&&

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

&&

$$

DISCUSSION...TS
AVIATION...SMW
MARINE...Blood