Area Forecast Discussion
Issued by NWS Honolulu, HI
FXHW60 PHFO 240152
Area Forecast Discussion
National Weather Service Honolulu HI
352 PM HST Sun Oct 23 2016
Breezy trade winds will continue overnight due to strong high
pressure far north of the area. The winds will gradually weaken
over the next couple of days as the high weakens just a bit.
Clouds and passing showers will favor windward and mauka areas and
will be highly dependent on incoming moisture sources. Another
strong high will build in north of the area later in the week with
breezy to locally windy trade winds expected once again.
High pressure located far to the north of the state is providing
for a rather breezy trade wind pattern across the area. The
atmosphere is rather stable due to an upper level ridge situated
over the area. Moisture embedded in the trades is providing for
some light passing showers over some windward and mauka locations
while most leeward locations are rather dry.
Over the next several days, a broad area of low pressure will be
present far to the northeast of the state while the ridge axis
associated with the high to our north gets nudged southward closer
to the state. This will cause a gradual drop off in trade wind
speeds but they will continue to blow. The upper level ridge is
forecast to remain near or over the area over the next several
days keeping the airmass rather stable. Rainfall chances over the
next several days will be highly dependent on incoming moisture
sources. Some of these rain sources may be in the from of frontal
remnants. The first one, though rather weak, is expected to move
across the area later tonight and Monday morning with a second one
possibly reaching the area around the Tuesday night time frame
with a third one possibly reaching the area around the Thursday
night time frame. With trade winds remaining in place, the
greatest chances of rainfall will be over windward and mauka
Toward the end of the week, a new strong high will build in to our
north, with another round of breezy to locally strong trade winds
expected. Clouds and passing showers will continue to favor
windward and mauka areas.
The strong and gusty trade winds will ease up slightly Monday.
AIRMET TANGO for low level turb over and immediately south through
west of the mountains will remain posted at least into tonight. An
upper level jet streak over the state is also helping to produce
upper level turb between FL330 and FL360, AIRMET TANGO is posted
and is expected to ease off over night.
Trade winds will help focus clouds and showers along the windward
slopes. Some showers will carry periods of MVFR CIGS/VIS, with an
increase expected overnight.
A Small Craft Advisory remains posted for most Hawaiian coastal
waters due to the strong trade winds. With the expected gradual
decrease in trade winds over the upcoming days, some zones will
gradually drop out of advisory status later tonight while
remaining up at least through Monday for the typically windy
waters around Maui County and The Big Island.
A High Surf Advisory remains posted along east facing shores due
to elevated surf created by the strong trade winds. Surf will
gradually lower over the next couple of days as the trade winds
decrease. A moderate size northwest swell is expected to arrive
Monday night, peak late Tuesday and Tuesday night, then lower
gradually Wednesday and Thursday. There will also be a series of
small southerly swells throughout the forecast period.
High Surf Advisory until 6 AM HST Monday for Kauai Windward-Oahu
Koolau-Olomana-Molokai Windward-Maui Windward West-Windward
Haleakala-South Big Island-Big Island North and East.
Small Craft Advisory until 6 PM HST Monday for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.
Small Craft Advisory until 6 AM HST Monday for Kauai Northwest
Waters-Kauai Leeward Waters-Kauai Channel-Oahu Windward Waters-
Oahu Leeward Waters-Kaiwi Channel-Maui County Windward Waters.