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000
FXHW60 PHFO 211959
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
959 AM HST Sun Apr 21 2024

.SYNOPSIS...
Moderate trade winds will gradually strengthen this afternoon with
breezy to locally strong trades expected through most of the
week. An increase in moisture is anticipated Tuesday into the
middle of the week, especially for the windward areas of Maui
County and the Big Island, where showery conditions remain in the
forecast.

&&

.DISCUSSION...
High pressure building far north of the state will gradually
strengthen the trade winds this afternoon with breezy to locally
strong trades expected through much of the upcoming week. Trade
winds may pick up a notch during the second half of the week as
the high strengthens north of the state.

This morning`s satellite imagery shows mostly dry conditions
across the state with a few light showers over windward areas.
Fair conditions are expected today through Tuesday with mainly
light scattered showers over windward areas. Starting Monday
night, we should see several pockets of moisture moving through
the state throughout the middle of the week with showery
conditions expected especially across the windward areas of Maui
County and the Big Island. Our typical fair trade wind weather
will likely return Thursday.

&&

.AVIATION...
Trade winds will increase to breezy strength this afternoon as
surface high pressure builds far north of the islands. The
increasing trade winds combined with stable conditions will
produce low level turbulence over and downwind of terrain, and
AIRMET Tango for moderate turbulence may be needed as early as
this afternoon. Pockets of moisture riding along the trade wind
flow will produce periods of MVFR conditions across windward
terrain. With the exception of isolated MVFR ceilings on the South
Kona slopes in the afternoon and evening, VFR will prevail over
leeward areas.


&&

.MARINE...
High pressure north-northwest of the state will drift east and
strengthen, resulting in trade winds strengthening over the
islands. A Small Craft Advisory is posted for the typical windy
waters around Maui County and the Big Island.

A moderate medium-period north swell will peak today, with surf
keeping below High Surf Advisory levels, then decrease Monday. A
small northwest swell is expected around Thursday. Surf along
east facing shores will rise below advisory levels with the
stronger winds and areas with north swell exposure. South facing
shores will continue at small levels as a series of small, medium
to long period energy will persist over the next several days.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory from noon today to 6 PM HST Tuesday for
Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island
Leeward Waters-Big Island Southeast Waters.


&&

$$


DISCUSSION...Kino
AVIATION...Wroe
MARINE...Foster