High Surf in Hawaii, December 25 to 28, 2016

Area Forecast Discussion...CORRECTED
National Weather Service Honolulu HI
1154 PM HST Sat Dec 24 2016

.SYNOPSIS...
Windy, gusty trades will prevail through the rest of the weekend
and for the first half of next week. Shower bearing clouds riding
in with the trades will favor the windward and mountain areas of
the larger islands especially during the nights and mornings.
The breezy trades will carry some of these showers into the lee
side of the smaller islands.

&&

.DISCUSSION...
A pocket of dry air is currently pushing through the islands
resulting in fewer showers compared to the past couple of nights.
Expect showers to be picking up after midnight or toward sunrise
Sunday, Christmas day, especially across the windward and mountain
areas of the larger islands. There are a couple of small showers
near Kailua- Kona town and the airport on the lee side of the Big
Islands. These showers will be ending in the next hour or two.

We should be returning back to a semi wet trade pattern by Sunday
evening. In the coming days, there will be a day or two where the
trade showers will be less. Also, the frequency of these showers
will trend less towards noon, then starts picking up towards
evening and lasting through the early morning hours. Usually, this
time of the year, with the shorter days. the afternoon and evening
showers along the Kona coast are far fewer than during the summer
months. But there could be one. Not very much at all in that part
of the Big Island.

A modestly strong surface high of 1030 mb will be gaining strength
as it passes slowly north of the islands tonight through Sunday
night. Thus, the trades will be strengthening as the evening
progresses, and this windy and gusty regime will persist through
Tuesday or Wednesday of next week.

The strong and breezy trades expected for Sunday and Monday have
warranted a wind advisory for zones prone to be sensitive to
breezy trades for places of acceleration such as the lee side of
the Kohala Mountains and the Waimea Saddle on the Big Island,
Lanai, and Kahoolawe. Other islands will also experience same
thing with windier,gustier conditions through ridges and valleys.

&&

.AVIATION...
High pressure north of the state will keep a breezy trade wind
flow in place through Sunday. Clouds and showers will favor
windward and mauka areas, but showers will also affect leeward
areas from time to time due to the strength of the trades. Brief
MVFR cigs/vsbys will be possible in windward areas as bands of
SHRA move through. Elsewhere, VFR conditions are expected to
prevail.

AIRMET Tango is in effect for low level turbulence over and
downwind of the terrain due to the breezy trade winds. The AIRMET
is expected to remain in place for the next couple of days.

AIRMET Sierra may be needed for mountain obscuration across windward
sections of some of the islands later tonight.

&&

.MARINE...
A strong high pressure system passing north of the state will
generate strong to gale force trade winds over all coastal waters
for the next few days. Beginning Sunday morning, A Gale Warning goes
into effect for the Pailolo and Alenuihaha Channels and waters south
of the Big Island, the windier areas sensitive to the trades. The
Gale Warning lasts to 6 pm HST Tuesday. A Small Craft Advisory (SCA)
is in effect for all coastal waters until 6 am HST Sunday, then for
the remaining waters after 6 am HST to until 6 PM HST Tuesday.

A larger northwest swell is slated to arrive Sunday morning.
Buoy 51001, located some 200 miles northwest of Kauai, shows a
rapid rise to 15 feet swell height this hour from 8 feet 3 hours
ago. This value is a couple of feet higher than forecast. So we
could be looking at warning level surf. We will monitor the buoys
for the overnight hours and see how is the swell trending. For
now, it is a high end high surf advisory for the north and west
facing shores of Niihau, Kauai, Oahu, and Molokai, and north
facing shores of Maui.

Looking ahead, a moderate northwest swell will arrive Monday
night and continue into Wednesday morning. Another large north
swell may impact the state around Thursday night.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory from 6 AM Sunday to 6 PM HST Monday for north
and west facing shores of Niihau, Kauai, Oahu, and Molokai, and
north facing shores of Maui.

CORRECTION...High Surf Advisory from 6 AM Sunday to 6 PM HST
Monday for EAST facing shores of EAST FACING SHORES OF KAUAI OAHU
MOLOKAI MAUI AND THE BIG ISLAND.

Small Craft Advisory until 6 AM HST Sunday for the Pailolo
and Alenuihaha Channels, and waters south of the Big Island.

Gale Warning from 6 AM Sunday to 6 PM HST Tuesday for Pailolo
and Alenuihaha Channels, and waters south of the Big Island.

Small Craft Advisory until 6 PM HST Tuesday for the remaining
Hawaiian waters.

&&

Lau...Discussion/Marine
Jelsema...Aviation