Wind Advisory 28, NWS Honolulu, HI

681 
WWHW70 PHFO 070131
NPWHFO

URGENT - WEATHER MESSAGE
National Weather Service Honolulu HI
331 PM HST Thu Sep 6 2018


HIZ014-015-070245-
/O.CAN.PHFO.WI.Y.0028.000000T0000Z-180907T0400Z/
Lanai Makai-Lanai Mauka-
331 PM HST Thu Sep 6 2018

...WIND ADVISORY IS CANCELLED...

The National Weather Service in Honolulu has cancelled the Wind
Advisory. Winds have dropped below advisory thresholds. 

$$

Area Forecast Discussion
National Weather Service Honolulu HI
810 PM HST Wed Sep 5 2018

.SYNOPSIS...
A moderately strong surface high far north of the islands will
move south for the next couple of days. Hurricane Norman is
forecast to pass northeast and north of the islands over the
weekend, interrupting the trades in the process. Hurricane Olivia
will approach the islands from the east early next week.

&&

.DISCUSSION...
A 1034 mb high about 1725 miles north of Kauai is forecast to move
gradually south in the next couple of days. The circulation of
Hurricane Norman will interact with the high, resulting in
initially a relatively breezy northeast wind flow across the
island chain through Thursday. As Norman tracks northwestward
to a position north of the islands by Saturday, our northeast
trade winds will be interrupted, bringing the winds to light and
variable. A warm humid airmass will descend on the islands. The
weather regime will also shift from a trade wind to a convective,
sea breeze one. Models are in agreement with some mainly spotty
afternoon/evening showers each day over the weekend.

In the mean time, the islands are currently in the subsidence part
of Hurricane Norman, resulting in minimal shower activity area-
wide today. However, we are likely at the tail end of this as we
expect a wetter, showery part of Norman to affect the islands.
We are expecting a slight rise in trade showers tonight, but a
bigger boost is likely to begin with windward Big Island late
Thursday morning, windward Maui Thursday afternoon, then the rest
of Maui County and Oahu Thursday night into Friday. The frequency
of the trade showers then trends down Friday night as we evolve
into a light wind, convective regime for the weekend. Kauai, will
also observe a few trade showers but the frequency appears to be
less compared to the neighbors. This forecast is based on the
track of Norman and is subject to change.

As of 730 pm HST, Hurricane Norman was centered about 370 miles
east of Hilo, moving toward the west-northwest around 9 mph. A
more northwest course is expected later tonight into Thursday,
taking Norman further away from the islands. It should be noted,
that Norman will be weakening as it head northwestward.

Depending on where Norman ends up, trades are expected to return
area- wide on Monday. The island weather thereafter depend on the
forecast path of Hurricane Olivia.

.MARINE...
High pressure north of the area will maintain locally breezy NE
trade winds through Thursday. In addition, east swell from
Hurricane Norman will produce seas greater than 10 feet across
exposed waters. Thus, the combo of these two has lead to a Small
Craft Advisory for most of the near-shore waters that is good
through 6 am HST Friday. The winds are expected to begin weakening
Thursday night as Hurricane Norman heads to an area northeast
and north of the state. The above normal swell is expected to
begin trending down on Friday, so the SCA could be be extended not
due to winds but seas 10 feet or higher.

Additionally, the east swell will produce large surf along east
facing shores of most of the islands. Latest buoy readings from
Pauwela, Maui (buoy 51205) and Hilo, Hawaii (buoy 51206) is
showing a steady rise and is expected to spread to the other
islands tonight and peak Thursday into Thursday night. A High
Surf Warning is in effect for east facing shores of the Big
Island, Maui, Molokai, Oahu, and Kauai through Thursday night.
Surf is expected to steadily decline on Friday into Saturday as
Norman tracks away from the islands.

Elsewhere, small south and southwest swells will maintain small
background surf along south facing shores through the weekend.
&&

.AVIATION...
Drier and more stable air aloft and stable stratocumulus clouds
moving in from the northeast will keep showers along mountain and
windward slopes at a minimum through this evening.

This stable layer aloft along with breezy to locally windy trade
winds at the surface will produce low level mountain wave
turbulence over and south through west of mountains across all
islands. AIRMET Tango remains in effect for low level moderate
turbulence for these areas through at least Thursday morning.

No other AIRMETs are in effect or expected through tonight.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Warning until 6 AM HST Friday 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 AM HST Friday for Kauai Northwest
Waters-Kauai Windward Waters-Kauai Channel-Oahu Windward Waters-
Kaiwi Channel-Maui County Windward Waters-Alenuihaha Channel-Big
Island Windward Waters-Big Island Southeast Waters.

Small Craft Advisory until 6 PM HST Thursday for Maalaea Bay-
Pailolo Channel.

&&

Lau/Kino/Bohlin