High Surf in Hawaii, October 8 to 11, 2021

Name: High Surf in Hawaii, October 8 to 11, 2021
Start: 2021-10-08T14:00
End: 2021-10-11T20:00
Location: Hawaii

October 8 to 11, 2021 · NWS HFO · 27 events in 27 counties and zones

Where it happened

Every event with a place to put it; 27 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

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Wind
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Winter weather
Heat and drought
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Fire, smoke and dust
Marine and coastal
Other

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The toll

Deaths: 1
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 27

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS HFO wrote it up.

The combination of a trade wind swell and a swell from the southern hemisphere generated surf of 6 to 12 feet along the east- and south-facing shores of all the islands. An individual, a 24-year-old male, was apparently swept off a rocky ledge by large waves near Makapuu Beach Park in East Oahu on the 11th. The search for the man, presumably drowned, was ended after three days without success. No significant property damage was reported.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Honolulu, HI wrote its last area forecast discussion before the first event at Oct 8, 9:48 AM HST, 4 hours 12 minutes earlier.

Area forecast discussion, Oct 8, 9:48 AM HST, 4 hours 12 minutes before

Area Forecast Discussion
National Weather Service Honolulu HI
948 AM HST Fri Oct 8 2021

.SYNOPSIS...
A windy trade wind weather pattern is setting up for the next few
days as strong lies north of the state. Clouds and passing
showers will favor windward and mauka areas with the trades
sufficiently strong enough to blow some brief passing showers over
to select leeward areas at times. A wetter trade wind weather
pattern is expected beginning late Sunday as an upper low and
increasing moisture moves in from the east. This wetter trade wind
pattern is expected to linger through Tuesday night. A more
typical trade wind weather pattern is expected Wednesday and
Thursday.

&&

.DISCUSSION...
Strong high pressure is centered far north of the state. This
places the islands in a breezy to windy trade wind environment. A
Wind Advisory is currently posted for portions of the state due to
the windy trades. Moisture embedded in the trades is providing
for some passing showers over windward and mauka areas with a few
brief showers falling over select leeward locations.

Satellite imagery shows an east to west oriented band of low
clouds a few hundred miles northeast of the state. This band of
clouds is forecast to move into the state tonight and Saturday
morning likely increasing shower activity across the area
especially windward and mauka locations. Some leeward locations
will also see some increase in showers as the strong trade winds
will be sufficient to blow the moisture downwind of terrain.

Beginning Sunday, an upper trough will move close the the island
vicinity from the east while an area of higher precipitable water
values begins to move in from the east as well. An increase in
showers is likely by late Sunday or Sunday night especially over
windward and mauka areas. Trade winds will continue to be in the
breezy to locally windy range so an increase in passing showers is
likely for some leeward locations as well. This wetter trade wind
pattern is expected to linger through about Tuesday night. A more
typical trade wind weather pattern will return for Wednesday and
Thursday.

&&

.AVIATION...
High pressure strengthening north of the state will bring breezy
trade winds to the islands. AIRMET TANGO remains in effect below 8000
feet over and immediately south through west of all mountains for
tempo moderate turbulence.

Scattered clouds and showers will carry in with the trade winds
focusing over windward slopes. Brief periods of MVFR conditions
and mountain obscurations will be present today, occasionally
reaching leeward sides of the smaller islands.

Showers and wind speeds will both increase tonight, likely
resulting in AIRMET Sierra for some windward portions of the
islands.

&&

.MARINE...
A series of strong highs building far to the north of the islands
will keep strong trade winds in place through the middle of next
week. The trades will be at their strongest tonight through the
weekend, before trending down slightly during the first half of
next week. A Small Craft Advisory (SCA) remains in effect for all
marine zones today due to winds and/or seas. As the trades winds
peak tonight through Sunday, gale force winds will be possible in
the typically windy waters around Maui and the Big Island, and as
a result, a Gale Watch is now in effect for these areas.
Elsewhere, an SCA remains in effect through 6 PM Sunday.

Long period forerunners from a building south swell have begun to
arrive in local waters. This swell is expected to build today and
tonight, then peak later in the weekend. Although the bulk of the
swell energy will pass east of Hawaii, advisory level surf
remains a possibility Saturday into Sunday as the swell peaks.
South shore surf will lower early next week, but a reinforcing
south swell will likely keep south shore surf above average
levels through the middle of next week. Surf along east facing
shores will build today, and become very rough tonight through the
weekend as the trade winds increase. East shore surf will rise to
well above seasonal levels by this afternoon, then likely reach
advisory levels Saturday through Monday. The trades will trend
down early next week, so we should see the very rough conditions
improve ever so slightly, with a gradual and slow lowering of east
shore surf through the middle of next week. The current west-
northwest swell will continue to gradually fade out today. No
other significant northwest swells are expected through the middle
of next week.

&&

.FIRE WEATHER...
With KBDI values above 600, low daytime relative humidities and
breezy to windy trades winds will keep Red Flag Warning conditions
in place through at least Saturday afternoon. A more moist airmass
is expected to move in from the east beginning Sunday. This will
likely allow relative humidity levels to stay above critical
values.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 6 PM HST Saturday for Kauai Leeward-Oahu
South Shore-Waianae Coast-Oahu North Shore-Olomana-Central Oahu-
Waianae Mountains-Molokai Leeward-Maui Leeward West-Maui Central
Valley-Leeward Haleakala-Kona-Kohala-Big Island Interior.

Wind Advisory until 6 PM HST Saturday for Kauai Mountains-
Waianae Coast-Central Oahu-Waianae Mountains-Lanai Mauka-
Kahoolawe-Maui Windward West-Maui Leeward West-Kohala-Big Island
Interior-East Honolulu-Honolulu Metro-Ewa Plain-Koolau Leeward-
Molokai Windward-Molokai Southeast-Molokai West-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.

Gale Watch from 6 PM HST this evening through Sunday afternoon
for Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island
Leeward Waters-Big Island Southeast Waters.

Small Craft Advisory until 6 PM HST this evening for Maalaea Bay-
Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big
Island Southeast Waters.

Small Craft Advisory until 6 PM HST Sunday 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.

&&

DISCUSSION...Burke
AVIATION...Foster
MARINE...Kinel

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

27 high surf. Local standard time, as filed.

High Surf, Niihau

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Niihau forecast zone
Reported by: Trained Spotter
Coordinates: 22.011, -159.705 (the zone’s center; the record gives no point)

High Surf, Kauai Southwest

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kauai Southwest forecast zone
Reported by: Trained Spotter
Coordinates: 22.011, -159.705 (the zone’s center; the record gives no point)

High Surf, Waianae Coast

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Waianae Coast forecast zone
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Olomana

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Olomana forecast zone
Deaths: 1 direct, 0 indirect
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Kahoolawe

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kahoolawe forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Maui Leeward West

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Maui Leeward West forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Kona

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kona forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

High Surf, Kauai East

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kauai East forecast zone
Reported by: Trained Spotter
Coordinates: 22.011, -159.705 (the zone’s center; the record gives no point)

High Surf, Kauai South

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kauai South forecast zone
Reported by: Trained Spotter
Coordinates: 22.011, -159.705 (the zone’s center; the record gives no point)

High Surf, East Honolulu

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: East Honolulu forecast zone
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Honolulu Metro

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Honolulu Metro forecast zone
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Ewa Plain

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Ewa Plain forecast zone
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Koolau Windward

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Koolau Windward forecast zone
Reported by: Trained Spotter
Coordinates: 21.455, -157.961 (the zone’s center; the record gives no point)

High Surf, Molokai Windward

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Molokai Windward forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Molokai Southeast

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Molokai Southeast forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Molokai Leeward South

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Molokai Leeward South forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Lanai Leeward

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Lanai Leeward forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Lanai South

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Lanai South forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Maui Central Valley South

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Maui Central Valley South forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Windward Haleakala

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Windward Haleakala forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, Kipahulu

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Kipahulu forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, South Maui/Upcountry

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: South Maui/Upcountry forecast zone
Reported by: Trained Spotter
Coordinates: 21.027, -156.788 (the zone’s center; the record gives no point)

High Surf, South Haleakala

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: South Haleakala forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

High Surf, Big Island South

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Big Island South forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

High Surf, Big Island Southeast

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Big Island Southeast forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

High Surf, Big Island East

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Big Island East forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

High Surf, Big Island North

When: October 8, 2:00 PM HST to October 11, 8:00 PM HST
Where: Big Island North forecast zone
Reported by: Trained Spotter
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

Event	Date	Age	Sex	Where	Kind
High Surf, Olomana	2021-10-11	24	Male	In Water	Direct

What these are

High Surf: Large waves breaking on the shore that caused damage, erosion or casualties.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Hawaii in 2021 Every state in 2021 This day in weather history Warnings in Hawaii, October 2021

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 983974, 983975, 983976, 983977, 983978, 983979, 983980, 983981, 983982, 983983, 983984, 983985, 983986, 983987, 983988, 983989, 983990, 983991, 983992, 983993, 983994, 983995, 983996, 983997, 983998, 983999, 984000.