Wildfire in Hawaii, August 8 to 16, 2023

Area Forecast Discussion
National Weather Service Honolulu HI
855 PM HST Mon Aug 7 2023

.SYNOPSIS...
Strong and potentially damaging easterly winds along with very
dry conditions will persist through Tuesday night as Hurricane
Dora passes far to the south. A return of a more typical trade
wind pattern is anticipated later in the week through the weekend.

&&

.DISCUSSION...
Deep layer ridging combined with an anomalously strong pressure
gradient over the area between Hurricane Dora passing well to the
south and the surface ridge to the north will support very strong
easterly winds and dry conditions into midweek. Guidance depicts
the winds steadily trending up overnight, with a peak expected
through the day Tuesday. Peak wind gust observations through this
evening have already surged into the 45 to 55 MPH range across
the state in the windier locations. Humidities dipped into the mid
40s this afternoon, which is well below normal. The upper air
sounding at Hilo and Lihue supported this with very dry profiles
along with a lowering inversion height (< 5000 ft). The inversion
height may dip toward the 3000 ft mark Tuesday, which will only
drive stronger accelerations after accounting for the island
terrain and peak mixing hours. For potential impacts regarding the
dry conditions and strong/potentially damaging winds, see the
latest High Wind and Red Flag Warnings.

For the second half of the week, expect a more seasonable breezy
trade wind pattern to return as the pressure gradient relaxes over
the region and Dora continues westward and away from the area.
More typical moisture levels will return to the state as well,
with showers mainly focusing along windward and mauka areas,
particularly during the overnight through morning hours each day.

&&

.AVIATION...
The pressure gradient continues to tighten across the state as
strong high pressure resides north of the islands and Hurricane
Dora passes by well to the south. Strong trades will persist
through the forecast period and bring tempo moderate to severe
low level turbulence to areas in the lee of mountains. Winds are
forecast to peak in intensity late Tuesday morning through Tuesday
afternoon.

The dry airmass will limit cloud and showers coverage tonight
through Wednesday.

AIRMET Tango remains in effect below 6000 feet over and
immediately south through west of mountains and all islands for
tempo moderate to isolated severe turbulence.

&&

.MARINE...
Hurricane Dora will continue on its westward track well passing
well south of the Hawaiian Islands, near gales to gale-force winds
with high seas are expected through Tuesday night. Winds will
begin to decline on Wednesday into strong trade winds and more
typical trade wind weather will return by Thursday. Seas will also
rapidly build with a mix of short-period wind waves and longer
period east-southeast swell from Hurricane Dora. Gale Warnings are
in place for the windier waters around Maui County and the Big
Island. A Small Craft Advisory is in effect for all remaining
waters. Conditions are expected to steadily improve Wednesday into
Thursday with our typical strong trade winds returning by
Thursday.

Surf along east facing shores will quickly ramp up tonight and
peak on Tuesday due to a combination of very strong winds, large
seas and a moderately sized, moderate period east-southeast swell
generated from Dora. The largest surf is expected over the
eastern end of the state, where surf heights will reach warning
levels from tonight through Tuesday across exposed east and
southeast facing shores. A downward trend is expected late Tuesday
through Thursday as trade winds and seas diminish to more typical
conditions. A High Surf Warning is in effect starting this evening
for all exposed east facing shores of the Big Island, Maui and
Molokai. A High Surf Advisory is in effect for east facing shores
of Oahu and Kauai starting this evening.

Surf along south facing shores should see an increase on Tuesday
due to a combination of long period southwest swell and medium
period southeast swell. A long period south-southwest swell will
arrive by Wednesday and will likely produce above average surf
along south facing shores on Wednesday and Thursday, before
diminishing through the end of the week.

&&

.FIRE WEATHER...
Very dry fuels (KDBI around 600) combined with strong and gusty
easterly winds and low humidities below 45 percent will produce
critical fire weather conditions through Tuesday night. See the
Red Flag Warning for more information.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 6 AM HST Wednesday for Niihau-Olomana-Kauai
East-Koolau Windward-Windward Haleakala-Kipahulu-Big Island East.

Red Flag Warning until 6 AM HST Wednesday for Kauai Leeward-Oahu
South Shore-Waianae Coast-Oahu North Shore-Olomana-Central Oahu-
Waianae Mountains-Molokai Leeward-Lanai Makai-Lanai Mauka-Maui
Leeward West-Maui Central Valley-Leeward Haleakala-Kona-South
Big Island-Kohala-Big Island Interior.

High Wind Warning until 6 AM HST Wednesday for Kauai Leeward-
Kauai Mountains-Waianae Coast-Oahu North Shore-Central Oahu-
Waianae Mountains-Lanai Mauka-Kahoolawe-Maui Windward West-Maui
Leeward West-Haleakala Summit-Kohala-Big Island Interior-Big
Island Summits-Kauai North-Kauai South-East Honolulu-Honolulu
Metro-Ewa Plain-Koolau Leeward-Molokai-Lanai Windward-Lanai
Leeward-Lanai South-Maui Central Valley North-Maui Central
Valley South-South Maui/Upcountry-South Haleakala-Big Island
South-Big Island Southeast-Big Island North.

High Surf Advisory until 6 PM HST Tuesday for Olomana-Kauai East-
East Honolulu-Koolau Windward.

High Surf Warning until 6 PM HST Tuesday for Maui Windward West-
Molokai Windward-Molokai Southeast-Windward Haleakala-Kipahulu-
Big Island Southeast-Big Island East-Big Island North.

Small Craft Advisory until 6 AM HST Wednesday for Kauai
Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters-
Kauai Channel-Oahu Windward Waters-Oahu Leeward Waters-Kaiwi
Channel-Maui County Windward Waters-Maui County Leeward Waters-
Big Island Windward Waters.

Gale Warning until 6 AM HST Wednesday for Maalaea Bay-Pailolo
Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island
Southeast Waters.

&&

DISCUSSION...Gibbs
AVIATION...Thomas
MARINE...Bohlin

Preliminary Local Storm Report
National Weather Service Honolulu HI
1153 PM HST Mon Aug 7 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0600 PM     Non-Tstm Wnd Dmg Kamehameha V Hwy MP 8.5 21.05N 156.88W
08/07/2023                   Maui               HI   Emergency Mngr

            Kamehameha V Hwy (Molokai) is closed between
            MP 8.5 and MP 10 due to two utility poles
            knocked down.

&&

AG