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000
FXHW60 PHFO 241339
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
339 AM HST Wed Apr 24 2024

.SYNOPSIS...
Breezy to locally windy trade winds will continue through Friday.
Expect enhanced trade wind showers through Thursday morning as a
band of unsettled clouds rides through the islands on the trade
winds. These showers will mainly form over windward and mountain
slopes, favoring the overnight to early morning hours. Trade wind
speeds will decrease slightly this weekend as high pressure
weakens to the north and a low pressure system deepens far
northwest of the island chain.

&&

.DISCUSSION...
The satellite imagery this morning continues to show a long band
of unstable clouds embedded in the trade wind flow creeping
towards Hawaii from the east. This unsettled cloud band will
produce periods of showers mainly over windward and mountain
areas, favoring the overnight to early morning hours. Expect
decreasing shower coverage during the daylight hours. This period
of enhanced showers will likely continue through Thursday morning.

In the big picture, a high pressure system will continue to linger
1000 miles northeast of the island chain through Friday,
producing breezy to locally trade winds across the Hawaii region.
Wind speeds may approach Wind Advisory thresholds in some wind
favored locations over the Big Island from Wednesday afternoon
into Thursday. However, we are expecting wind speeds to remain
just below advisory thresholds for these windier zones.

This high center will drift farther east from Friday to Saturday
decreasing trade wind speeds as a cut off low pressure system
deepens approximately 1000 miles northwest of Kauai. The cut off
low at this time remains too far northwest of the islands to
impact island weather. Expect winds to veer from a more east to
southeast direction this weekend, and to decrease into more
moderate trade wind levels from Saturday to Sunday. The weather
forecast for this weekend appears fairly dry and sunny, another
great weekend for outdoor activities.

&&

.AVIATION...
Breezy to locally strong trade winds will prevail for the next
couple of days as a surface ridge remains to the north of the
islands. Cloud bands with SHRA are moving in bringing MVFR conds
to windward and mauka areas. Isol SHRA may make it to lee sides
periodically dropping conds to MVFR but those should be brief.

AIRMET Sierra for mtn obsc is in effect for all islands and
windward Big Island.

AIRMET Tango is in effect for moderate low level turb downwind of
the terrain for all islands.

&&

.MARINE...
An area of high pressure will meander northeast of the state over
the next few days, driving strong to locally near gale trades.
The high is forecast to weaken over the weekend as a deep low
develops northwest of the area. A Small Craft Advisory remains in
effect for all Hawaiian coastal waters through tonight and will
likely need to be extended for all or most waters through
Thursday.

Surf heights along all shores will remain below advisory thresholds
through the forecast period. A small, medium period northwest
swell will fill in tonight, peak Thursday night. Another
small, medium period northwest pulse will fill in Friday, peak
late Friday into Saturday, and subside Sunday. Choppy, rough surf
is expected all week along east facing shores due to persistent
trade winds. A slight downtrend in surf is expected along east
facing shores over the weekend as trades ease. South facing
shores will continue to see small background swell pulses through
the forecast period.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 AM HST Thursday for all Hawaiian
waters-

&&

$$

DISCUSSION...Bohlin
AVIATION...Walsh
MARINE...Almanza