Hawaii, 2011

High Surf in Hawaii, September 1, 2011

September 1, 2011 · NWS HFO · 16 events in 16 counties and zones

A swell from the southern hemisphere produced surf of 6 to 12 feet along the south-facing shores of all the islands. Lifeguards were busy with issuing warnings to swimmers and surfers, and performing rescues, as this unusually high surf affected the south shores.

Where it happened

Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
16

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.

A swell from the southern hemisphere produced surf of 6 to 12 feet along the south-facing shores of all the islands. Lifeguards were busy with issuing warnings to swimmers and surfers, and performing rescues, as this unusually high surf affected the south shores. There were no reports of significant injuries or property damage, however. This episode is a continuation of one that began at the end of August.

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 Aug 31, 8:30 PM HST, 3 hours 30 minutes earlier.

Area forecast discussion, Aug 31, 8:30 PM HST, 3 hours 30 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST WED AUG 31 2011

.SYNOPSIS...
LIGHT TO MODERATE TRADE WINDS WILL DIMINISH LATE IN THE WEEKEND.
SHOWERS WILL FAVOR WINDWARD AND MAUKA SECTIONS. DANGEROUS SURF WILL
CONTINUE ALONG SOUTH FACING SHORES THROUGH THURSDAY.

&&

.DISCUSSION...
A SURFACE HIGH CENTERED FAR NORTHEAST OF HAWAII WILL MAINTAIN LIGHT
TO MODERATE TRADE WINDS THROUGH SATURDAY. A DEEPENING LOW IN THE
GULF OF ALASKA WILL ERODE THE HIGH AND PUSH A WEAK RIDGE SOUTHWARD
TO JUST NORTH OF THE ISLANDS ON SUNDAY. THE SLACK PRESSURE GRADIENT
SOUTH OF THE RIDGE WILL RESULT IN LIGHTER WINDS THAT WILL LINGER
OVER THE STATE WELL INTO NEXT WEEK.

ALOFT...A MIDDLE AND UPPER LEVEL LOW NORTH OF KAUAI IS MOVING AWAY
TO THE NORTHWEST...AND AN UPPER LEVEL RIDGE IS SNEAKING IN FROM THE
NORTHEAST IN THE WAKE OF THE LOW. PRESSURE RISES OVER THE PAST 24
HOURS AND A LARGE AREA OF STABLE STRATOCUMULUS HEADING WEST TOWARD
THE ISLANDS ARE CLUES THAT THE STABILIZING PROCESS IS IN PROGRESS.
THE UPPER RIDGE WILL REMAIN OVERHEAD THROUGH NEXT WEEK...KEEPING US
IN MOSTLY DRY WEATHER.

&&

.AVIATION...
WINDWARD TERRAIN/TERMINALS MAY SEE ISOLATED MVFR CONDS AFT 08Z...
OTHERWISE VFR CONDS WILL PREVAIL. A LARGE BKN-OVC SC FIELD WITH CIGS
ABV 030 AND TOPS BLO 060 WILL MOVE W ACROSS THE STATE OVERNIGHT.

LGT-MOD TRADES CONTINUE AOB 070-080. A DEPARTING UPPER LOW TO THE NW
IS MAINTAINING WSW FLOW ABV 080.

&&

.MARINE...
THE SOUTH SWELL CONTINUES TO LOWER. THE PROCESS IS SLOW HOWEVER...
SO ADVISORY LEVEL SURF WILL PERSIST THROUGH THURSDAY. THE SURF WILL
DROP BELOW THE 8 FOOT ADVISORY THRESHOLD THURSDAY NIGHT.

A WEST SWELL GENERATED BY DISTANT TROPICAL CYCLONE TALAS WILL REACH
WEST FACING SHORES THURSDAY. TALAS HAS BEEN A SLOW MOVER FOR A LONG
TIME...SO THE SURF WILL LINGER AT LEAST THROUGH THE WEEKEND.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 PM HST THURSDAY FOR SOUTH FACING SHORES
OF ALL ISLANDS.

&&

CRAIG

The radar

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

Open the radar archive at this moment

Event by event

16 high surf. Local standard time, as filed.

High Surf, Niihau

When
September 1, 12:00 AM HST to 3:00 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 Windward

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Kauai Windward forecast zone
Reported by
Trained Spotter

High Surf, Kauai Leeward

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Kauai Leeward forecast zone
Reported by
Trained Spotter
Coordinates
22.011, -159.705 (the zone’s center; the record gives no point)

High Surf, Oahu South Shore

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Oahu South Shore forecast zone
Reported by
Trained Spotter

High Surf, Waianae Coast

When
September 1, 12:00 AM HST to 3:00 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, Molokai Windward

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Molokai Windward forecast zone
Reported by
Trained Spotter

High Surf, Molokai Leeward

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Molokai Leeward forecast zone
Reported by
Trained Spotter

High Surf, Lanai Makai

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Lanai Makai forecast zone
Reported by
Trained Spotter

High Surf, Kahoolawe

When
September 1, 12:00 AM HST to 3:00 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
September 1, 12:00 AM HST to 3:00 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, Maui Central Valley

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Maui Central Valley forecast zone
Reported by
Trained Spotter

High Surf, Windward Haleakala

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Windward Haleakala forecast zone
Reported by
Trained Spotter

High Surf, Leeward Haleakala

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Leeward Haleakala forecast zone
Reported by
Trained Spotter

High Surf, Kona

When
September 1, 12:00 AM HST to 3:00 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, South Big Island

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
South Big Island forecast zone
Reported by
Trained Spotter

High Surf, Big Island North and East

When
September 1, 12:00 AM HST to 3:00 PM HST
Where
Big Island North and East forecast zone
Reported by
Trained Spotter

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

More

Every storm in Hawaii in 2011Every state in 2011This day in weather historyWarnings in Hawaii, September 2011

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: 340043, 340044, 340045, 340046, 340047, 340048, 340049, 340050, 340051, 340052, 340053, 340054, 340055, 340056, 340057, 340058.