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fxhw60 phfo 071955 
afdhfo

Area forecast discussion
National Weather Service Honolulu HI
955 am HST Sat Dec 7 2019

Synopsis...
a surface ridge near the area will maintain gentle winds and
mostly dry weather through early next week. A front approaching
from the northwest may produce Rainier weather by the end of next
week.

&&

Discussion...
the 8 am surface analysis shows a 1020 mb surface high 900 miles
northeast of the area at 31n 146w with a ridge extending southwest
to 450 miles north of Kauai. The ridge is producing locally fresh
trade winds over water around The Big Island of Hawaii and light
trade winds elsewhere. Skies are mostly sunny around the islands
this morning.

The ridge will shift south slowly over the next few days ahead of
a front approaching from the northwest. The ridge will produce
light winds and mostly dry weather. Sea breezes will produce some
afternoon clouds, but the atmosphere will be too dry and stable to
produce much rain. Nighttime land breezes will bring clearing
skies. The front will stall northwest of Kauai Monday and
dissipate.

A stronger front will approach from the northwest during the
middle of next week. Rainfall will start to increase Wednesday ahead
of the front. The front may bring breezy trade winds and
widespread showers Thursday and Friday.

&&

Aviation...
there are no airmets in effect, and none are expected over the
next couple of days. VFR conditions will prevail.

Weak easterly tradewinds today will turn from the southeast
tonight as a front approaches from the northwest. The light winds
will allow daytime sea breezes and nighttime land breeze to form
over the islands. Shower activity will be limited to mainly
windward and mountain areas with some afternoon convection
bringing added cloud cover.

&&

Marine...
high pressure is moving off to a position far northeast of the area
while a front approaches from the northwest. This will result in light
winds through Sunday. The mean background flow over open waters will
generally be from the east-southeast. Light trade winds will return
Monday and Tuesday as the front dissipates near Kauai. Another front
will approach the area on Wednesday with winds becoming light once
again.

A north-northeast swell building in today will cause seas to reach
or exceed 10 feet over portions of the area. Thus a Small Craft Advisory
is posted through tonight for waters exposed to this swell. This swell
may also produce Harbor surges at both Kahului and Hilo harbors.

The north-northeast swell is expected to produce warning level
surf along exposed east facing shores and advisory level surf
along exposed north facing shores. The advisory and warning is
currently in effect through tonight. This swell will lower
gradually Sunday and Monday.

A new northwest swell is expected to arrive starting tomorrow,
then gradually build Monday through Tuesday. Surf from this swell
will reach advisory levels along north and west facing shores. A
much larger northwest swell is expected Wednesday and Thursday
with warning level surf predicted based on the latest guidance.

No other significant swells are expected.

&&

Hfo watches/warnings/advisories...
high surf warning until 6 am HST Sunday for east facing shores of
Kauai, Oahu, Molokai, Maui and The Big Island of Hawaii.

High surf advisory until 6 am HST Sunday for north facing shores
of Niihau, Kauai, Oahu, Molokai, Maui and The Big Island of
Hawaii.

&&

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