Alert archive / Hawaii / High Surf Warnings in 2021

High Surf Warning 2, NWS Honolulu, HI

January 13, 2021Honolulu County, Kauai County, Kalawao County, Hawaii

NWS Honolulu, HI issued this high surf warning at Jan 13, 2021, 3:07 PM HST for Honolulu County, Kauai County, Kalawao County, Hawaii. It took effect at Jan 14, 2021, 12:00 AM HST. It was in force for 27 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jan 13, 2021, 3:07 PM HST (01:07 UTC)
In effect from
Jan 14, 2021, 12:00 AM HST
Expired
Jan 15, 2021, 3:22 AM HST
In force
27 hr
Issued by
NWS Honolulu, HI

Counties Honolulu County, HI, Kalawao County, HI, Kauai County, HI

The radar

The Molokai radar (PHMO), 116 km from the middle of the area, began a volume at 01:08 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lihue, (PHLI), launched 00:00Z, 1.1 hours before the alert went out and 127 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lihue, at 00:00Z on 2021-01-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lihue, at 00:00Z on 2021-01-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
6 J/kg
Mixed-layer CIN
-537 J/kg
Mixed-layer LCL
1322 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

149 
WHHW40 PHFO 140107
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
307 PM HST Wed Jan 13 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI...

.A very large northwest swell will roll through the coastal 
waters tonight and Thursday producing very large surf along north
and west facing shores of the smaller islands. The swell will be 
mostly blocked from reaching the Big Island.

HIZ001>003-006>008-012-013-018>020-141415-
/O.NEW.PHFO.SU.W.0002.210114T1000Z-210115T0400Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Molokai Windward-Molokai Leeward-
Maui Leeward West-Maui Central Valley-Windward Haleakala-
307 PM HST Wed Jan 13 2021

...HIGH SURF WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 6 PM 
THURSDAY...

* WHAT...Dangerously large breaking waves of 20 to 25 feet along 
  north facing shores and 15 to 20 feet along west facing shores.

* WHERE...Portions of Kauai, Maui, Molokai, Niihau and Oahu 
  Hawaii.

* WHEN...From midnight tonight to 6 PM Thursday.

* IMPACTS...High. Expect ocean water occasionally sweeping across
  portions of beaches, very strong breaking waves, and strong
  currents. Breaking waves may occasionally impact harbors making
  navigating the harbor channels dangerous. Anyone entering the
  water could face significant injury or death. Coastal flooding
  is possible.

* ADDITIONAL DETAILS...The very large swell will be accompanied by
  onshore winds making the surf very rough and sloppy. Very high
  tides will during the late night and early morning hours will
  increase the amount of wave runup.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Stay well away from the shoreline along the affected coasts. Be
prepared for coastal erosion with some waves reaching coastal
roads. Mariners should be extra careful entering and leaving
harbors.

&&

$$
Donaldson
4 follow-up statements
482 
WHHW40 PHFO 141344
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
344 AM HST Thu Jan 14 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI...
...HIGH SURF ADVISORY FOR NORTH FACING SHORES OF THE BIG ISLAND...

.A very large northwest swell will roll through the coastal
waters today and tonight producing very large surf along north 
and west facing shores of the smaller islands. A more northerly
overlapping swell will bring advisory level surf to the north
facing shores of the Big Island.

HIZ018-141445-
/O.CAN.PHFO.SU.W.0002.000000T0000Z-210115T0400Z/
Maui Leeward West-
344 AM HST Thu Jan 14 2021

...HIGH SURF WARNING IS CANCELLED...

Surf along leeward west facing shores of Maui will not reach 
warning levels.

$$

HIZ017-150245-
/O.EXB.PHFO.SU.W.0002.000000T0000Z-210115T1600Z/
Maui Windward West-
344 AM HST Thu Jan 14 2021

...HIGH SURF WARNING IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Dangerously large breaking waves of 25 to 35 feet along
  north facing shores.

* WHERE...North facing shores of Maui.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...High. Expect ocean water occasionally sweeping 
  across portions of beaches, very strong breaking waves, and 
  strong currents. Breaking waves may occasionally impact 
  harbors making navigating the harbor channels dangerous. 
  Anyone entering the water could face significant injury or 
  death. Coastal flooding is possible.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

&&

$$

HIZ001>003-006>008-012-013-019-020-150245-
/O.EXT.PHFO.SU.W.0002.000000T0000Z-210115T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Molokai Windward-Molokai Leeward-
Maui Central Valley-Windward Haleakala-
344 AM HST Thu Jan 14 2021

...HIGH SURF WARNING NOW IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Dangerously surf of 25 to 35 feet along north facing 
  shores and 20 to 25 feet along west facing shores.

* WHERE...North and west facing shores of Niihau, Kauai, Oahu, 
  Molokai and north facing shores of Maui.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...High. Expect ocean water occasionally sweeping 
  across portions of beaches, very strong breaking waves, and 
  strong longshore and rip currents. Breaking waves may 
  occasionally impact harbors making navigating the harbor 
  channel dangerous.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north and west swells during the early 
  morning hours. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

&&

$$

HIZ025-150245-
/O.NEW.PHFO.SU.Y.0005.210114T1344Z-210115T1600Z/
Big Island North and East-
344 AM HST Thu Jan 14 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Surf of 12 to 16 feet along north facing shores of the
  Big Island.

* WHERE...North facing shores of the Big Island.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$
348 
WHHW40 PHFO 141352 AAA
CFWHFO

Coastal Hazard Message...UPDATED
National Weather Service Honolulu HI
352 AM HST Thu Jan 14 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... 
...HIGH SURF ADVISORY FOR NORTH FACING SHORES OF THE BIG 
ISLAND...

.A very large northwest swell will roll through the coastal
waters today and tonight producing very large surf along north
and west facing shores of the smaller islands. A more northerly
overlapping swell will bring advisory level surf to the north
facing shores of the Big Island.

HIZ001>003-006>008-012-013-017-019-020-150300-
/O.CON.PHFO.SU.W.0002.000000T0000Z-210115T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Molokai Windward-Molokai Leeward-
Maui Windward West-Maui Central Valley-Windward Haleakala-
352 AM HST Thu Jan 14 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Dangerously large breaking waves of 25 to 35 feet along 
  north facing shores.

* WHERE...North facing shores of Maui.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...High. Expect ocean water occasionally sweeping 
  across portions of beaches, very strong breaking waves, and 
  strong currents. Breaking waves may occasionally impact 
  harbors making navigating the harbor channels dangerous. 
  Anyone entering the water could face significant injury or 
  death. Coastal flooding is possible.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

&&

$$

HIZ025-150300-
/O.CON.PHFO.SU.Y.0005.000000T0000Z-210115T1600Z/
Big Island North and East-
352 AM HST Thu Jan 14 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Surf of 12 to 16 feet along north facing shores of the 
  Big Island.

* WHERE...North facing shores of the Big Island.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$
435 
WHHW40 PHFO 150138
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
338 PM HST Thu Jan 14 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... 
...HIGH SURF ADVISORY FOR NORTH FACING SHORES OF THE BIG 
ISLAND...

.A very large northwest swell will hold through tonight, producing
very large surf along north and west facing shores of the smaller
islands, then quickly lower Friday. A more northerly overlapping 
swell will bring advisory level surf to the north facing shores of
the Big Island.

HIZ001>003-006>008-012-013-017-019-020-151445-
/O.CON.PHFO.SU.W.0002.000000T0000Z-210115T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Molokai Windward-Molokai Leeward-
Maui Windward West-Maui Central Valley-Windward Haleakala-
338 PM HST Thu Jan 14 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Dangerous surf of 25 to 30 feet along north facing shores
  and 15 to 20 feet along west facing shores.

* WHERE...North and west facing shores of Niihau, Kauai, Oahu, 
  Molokai and north facing shores of Maui.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...High. Expect ocean water occasionally sweeping 
  across portions of beaches, very strong breaking waves, and 
  strong currents. Breaking waves may occasionally impact 
  harbors making navigating the harbor channels dangerous. 
  Anyone entering the water could face significant injury or 
  death. Coastal flooding is possible.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

&&

$$

HIZ025-151445-
/O.CON.PHFO.SU.Y.0005.000000T0000Z-210115T1600Z/
Big Island North and East-
338 PM HST Thu Jan 14 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST FRIDAY...

* WHAT...Surf of 12 to 16 feet along north facing shores of the 
  Big Island.

* WHERE...North facing shores of the Big Island.

* WHEN...Until 6 AM HST Friday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

* ADDITIONAL DETAILS...The combination of large surf coinciding 
  with peak monthly high tides may worsen beach erosion along 
  shorelines exposed to north swell during the early morning 
  hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$
319 
WHHW40 PHFO 151322
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
322 AM HST Fri Jan 15 2021

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU 
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI AND BIG 
ISLAND...

.The current northwest swell will slowly trend lower today. Surf 
heights will remain at advisory levels today for north and west 
facing shores of the smaller islands, including north facing 
shores of Maui and the Big Island.

HIZ001>003-006>008-012-013-017-019-020-160230-
/O.CAN.PHFO.SU.W.0002.000000T0000Z-210115T1600Z/
/O.EXB.PHFO.SU.Y.0005.000000T0000Z-210116T0400Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Molokai Windward-Molokai Leeward-
Maui Windward West-Maui Central Valley-Windward Haleakala-
322 AM HST Fri Jan 15 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 6 PM HST THIS EVENING...
...HIGH SURF WARNING IS CANCELLED...

* WHAT...Surf of 10 to 15 feet along north facing shores and 8 to
  12 for west facing shores.

* WHERE...North and west facing shores of Niihau, Kauai, Oahu,
  Molokai and north facing shores of Maui.

* WHEN...Until 6 PM HST this evening.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$

HIZ025-160230-
/O.EXT.PHFO.SU.Y.0005.000000T0000Z-210116T0400Z/
Big Island North and East-
322 AM HST Fri Jan 15 2021

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM HST THIS EVENING...

* WHAT...Surf of 10 to 15 feet along north facing shores.

* WHERE...North facing shores of the Big Island.

* WHEN...Until 6 PM HST this evening.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$

The office that day

Everything else NWS Honolulu, HI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 14, 3:44 AM HSTHigh Surf AdvisoryHFOHonolulu, Kauai, Kalawao48 hr

Nearby

High Surf Warnings in Hawaii, 2021Every high surf warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.