Alert archive / Hawaii / High Surf Advisories in 2018
High Surf Advisory 21, NWS Honolulu, HI
NWS Honolulu, HI issued this high surf advisory at Apr 8, 2018, 3:33 PM HST for Honolulu County, Kauai County, Kalawao County, Hawaii. It took effect at Apr 9, 2018, 3:27 AM HST. It was in force for 17 hr.
The area
The counties it named.
The facts
- Issued
- Apr 8, 2018, 3:33 PM HST (01:33 UTC)
- In effect from
- Apr 9, 2018, 3:27 AM HST
- Expired
- Apr 9, 2018, 8:31 PM HST
- In force
- 17 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 01:33 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
Hilo, (PITO), launched 00:00Z, 1.6 hours before the alert went out and 391 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.
- Mixed-layer CAPE
- 609 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 773 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 66 m²/s²
- 0-3 km storm-relative helicity
- 111 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 4.8
The text
As transmitted.
316 WHHW40 PHFO 090133 CFWHFO Coastal Hazard Message National Weather Service Honolulu HI 333 PM HST Sun Apr 8 2018 ...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... .A new northwest swell will fill in tonight and reach advisory level Monday morning. This swell will peak Monday night, then slowly subside through Wednesday. HIZ001>003-007>009-012-013-017-020-091445- /O.NEW.PHFO.SU.Y.0021.180409T1600Z-180411T0400Z/ Niihau-Kauai Windward-Kauai Leeward-Oahu North Shore-Oahu Koolau- Olomana-Molokai Windward-Molokai Leeward-Maui Windward West- Windward Haleakala- 333 PM HST Sun Apr 8 2018 ...HIGH SURF ADVISORY IN EFFECT FROM 6 AM MONDAY TO 6 PM HST TUESDAY... The National Weather Service in Honolulu has issued a High Surf Advisory, which is in effect from 6 AM Monday to 6 PM HST Tuesday. * SURF...Along north facing shores of Niihau, Kauai, Oahu, Molokai, and Maui...15 to 20 feet. Along west facing shores of Niihau, Kauai, Oahu, and Molokai...12 to 16 feet. * TIMING...Monday morning through Tuesday afternoon. * 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. && $$
3 follow-up statements
293 WHHW40 PHFO 091327 CFWHFO Coastal Hazard Message National Weather Service Honolulu HI 327 AM HST Mon Apr 9 2018 ...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... .A new northwest swell will build to advisory levels today, and peaking Monday night, then slowly subsiding through Wednesday. HIZ001>003-007>009-012-013-017-020-100230- /O.EXT.PHFO.SU.Y.0021.180409T1327Z-180411T0400Z/ Niihau-Kauai Windward-Kauai Leeward-Oahu North Shore-Oahu Koolau- Olomana-Molokai Windward-Molokai Leeward-Maui Windward West- Windward Haleakala- 327 AM HST Mon Apr 9 2018 ...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 PM HST TUESDAY... * SURF...Along north facing shores of Niihau, Kauai, Oahu, Molokai, and Maui, 15 to 20 feet. Along west facing shores of Niihau, Kauai, Oahu, and Molokai, 12 to 16 feet. * TIMING...Through Tuesday afternoon. * IMPACTS...Moderate...Expect strong breaking waves, shore break, and strong longshore and rip currents making swimming difficult and dangerous. PRECAUTIONARY/PREPAREDNESS ACTIONS... Beachgoers, swimmers, and surfers should heed all advice given by ocean safety officials and exercise caution. && $$
419 WHHW40 PHFO 100128 CFWHFO Coastal Hazard Message National Weather Service Honolulu HI 328 PM HST Mon Apr 9 2018 ...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... .The northwest swell will peak tonight, then slowly subside through Wednesday. HIZ001>003-007>009-012-013-017-020-101430- /O.CON.PHFO.SU.Y.0021.000000T0000Z-180411T0400Z/ Niihau-Kauai Windward-Kauai Leeward-Oahu North Shore-Oahu Koolau- Olomana-Molokai Windward-Molokai Leeward-Maui Windward West- Windward Haleakala- 328 PM HST Mon Apr 9 2018 ...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 PM HST TUESDAY... * SURF...Along north facing shores of Niihau, Kauai, Oahu, Molokai, and Maui, 15 to 20 feet. Along west facing shores of Niihau, Kauai, Oahu, and Molokai, 12 to 16 feet. * TIMING...Through Tuesday afternoon. * 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. && $$ BRENCHLEY
160 WHHW40 PHFO 100631 AAA CFWHFO Coastal Hazard Message...UPDATED National Weather Service Honolulu HI 831 PM HST Mon Apr 9 2018 ...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU AND MOLOKAI AND NORTH FACING SHORES OF MAUI... .A large northwest swell is quickly building down the island chain this evening and is coming in much larger than predicted. Surf will peak tonight into early Tuesday morning at and above warning levels, then drop to advisory levels through the day Tuesday. HIZ001>003-007>009-012-013-017-020-101945- /O.UPG.PHFO.SU.Y.0021.000000T0000Z-180411T0400Z/ /O.NEW.PHFO.SU.W.0007.180410T0631Z-180410T1600Z/ Niihau-Kauai Windward-Kauai Leeward-Oahu North Shore-Oahu Koolau- Olomana-Molokai Windward-Molokai Leeward-Maui Windward West- Windward Haleakala- 831 PM HST Mon Apr 9 2018 ...HIGH SURF WARNING IN EFFECT UNTIL 6 AM HST TUESDAY... The National Weather Service in Honolulu has issued a High Surf Warning, which is in effect until 6 AM HST Tuesday. The High Surf Advisory is no longer in effect. * SURF...Along north and west facing shores of Niihau and Kauai, and north facing shores of Oahu, Molokai, and Maui, 20 to 30 feet. Along west facing shores of Molokai, 12 to 20 feet. * TIMING...through early Tuesday. * IMPACTS...High...Expect ocean water occasionally sweeping across portions of beaches, very strong breaking waves, beach erosion, and strong longshore and rip currents. Breaking waves may occasionally impact harbors making navigating the harbor channel dangerous. PRECAUTIONARY/PREPAREDNESS ACTIONS... These dangerous conditions mean that only highly experienced persons should enter the water. Inexperienced persons should remain off beaches and adjacent beachfront areas. Large breaking surf, significant shorebreak, and dangerous currents make entering the water very hazardous. && $$ HIZ006-101600- /O.NEW.PHFO.SU.W.0007.180410T0631Z-180410T1600Z/ Waianae Coast- 831 PM HST Mon Apr 9 2018 ...HIGH SURF WARNING IN EFFECT UNTIL 6 AM HST TUESDAY... The National Weather Service in Honolulu has issued a High Surf Warning, which is in effect until 6 AM HST Tuesday. The High Surf Advisory is no longer in effect. * SURF...Along west facing shores of Oahu, 12 to 20 feet. * TIMING...through early Tuesday. * IMPACTS...High...Expect ocean water occasionally sweeping across portions of beaches, very strong breaking waves, beach erosion, and strong longshore and rip currents. Breaking waves may occasionally impact harbors making navigating the harbor channel dangerous. PRECAUTIONARY/PREPAREDNESS ACTIONS... These dangerous conditions mean that only highly experienced persons should enter the water. Inexperienced persons should remain off beaches and adjacent beachfront areas. Large breaking surf, significant shorebreak, and dangerous currents make entering the water very hazardous. && $$ Gibbs
The office that day
Everything else NWS Honolulu, HI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 8, 3:31 PM HST | Small Craft Advisory | HFO | 4 days | |
| Apr 8, 3:43 PM HST | Areal Flood Advisory | HFO | Hawaii | 3 hr |
| Apr 8, 6:22 PM HST | Areal Flood Advisory | HFO | Hawaii | 3 hr |
| Apr 9, 5:17 AM HST | Areal Flood Advisory | HFO | Kalawao | 3 hr |
Nearby
High Surf Advisories in Hawaii, 2018Every high surf advisory in 2018
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.