A large north swell brought twenty to twenty six foot waves to north facing shores and ten to fifteen foot waves to east facing shores. These waves brought dangerous conditions to affected shorelines as well as beach runup.
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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.
The episode as NWS HFO wrote it up.
A large north swell brought twenty to twenty six foot waves to north facing shores and ten to fifteen foot waves to east facing shores. These waves brought dangerous conditions to affected shorelines as well as beach runup.
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 Apr 4, 3:17 PM HST, 2 hours 43 minutes earlier.
Area Forecast Discussion National Weather Service Honolulu HI 317 PM HST Fri Apr 4 2025 .SYNOPSIS... Breezy trades will focus showers associated with a dissipating front over Oahu and Kauai into Saturday while dry weather and light winds prevail elsewhere. Trades then return to the remainder of the area tonight and continue through next week. && .DISCUSSION... Regional observations and model analyses this afternoon reveal a dissipating cold front stalled in the Kauai Channel beneath a mostly opaque canopy of high clouds aloft. Strong southwesterlies aloft ensure high clouds will persist for the remainder of today into tonight helping to tamp down late afternoon temperatures. Radar composite shows the focus of showers associated with said front mainly over the Kauai Channel at press time with isolated activity noted over portions of Windward Oahu as breezy trades make their return to the western end of the state. This band of frontal moisture will favor enhanced showers over windward and mauka sections of Oahu and especially Kauai tonight into tomorrow until building trades usher it west of the state by late Saturday. Elsewhere, breezy trades gradually return as governing high pressure becomes established near 30N. This in turn favors a return to a typical distribution of clouds and showers over windward and mauka areas going forward. Little change then for the remainder of the forecast period as breezy trades prevail. && .AVIATION... A dissipating front over the western end of the state has stalled across the Kauai Channel with breezy northeasterly trade winds building in its wake. A band of enhanced clouds and showers will persist across the Kauai Channel and portions of Kauai and Oahu through this evening as moisture lingers along the dissipating frontal boundary, then lift back towards Kauai overnight into tomorrow. Periods of MVFR conditions are likely within the heavier showers, with brief periods of IFR possible. As such, AIRMET Sierra remains in effect for mountain obscuration for all of Kauai and north through east sections of Oahu through this evening. The eastern half of the state will see moderate to locally breezy southeasterly winds through the evening before easterly trade winds return tonight. Overall, VFR conditions will prevail across this end of the state. AIRMET Tango is in effect for tempo moderate upper level turbulence and is expected to continue through the evening. && .MARINE... Trade winds will build tonight and become locally strong and gusty during the weekend. A dissipating front stalled in the Kauai Channel will drift westward over Kauai late tonight and Saturday. Meanwhile, strong high pressure far northwest of the state will build and creep eastward. As a result, fresh to locally strong trade winds, which area already observed around Kauai, will develop across the typically windy waters around the Big Island and Maui County tonight and will persist through at least Sunday. A Small Craft Advisory (SCA) remains in effect around Kauai and has been expanded to waters around the Big Island and Maui County. Trades will likely ease slightly Monday and Tuesday as the surface high weakens, but trades are expected to build again by Wednesday. A north-northwest (330-340 deg) swell will continue to build down the island chain tonight, followed by a large north (340-350 deg) swell Saturday and Sunday. Recent observations from buoy 51001 have shown the new north-northwest swell coming in above guidance, and High Surf Advisory conditions are expected across most north facing shores tonight and early Saturday. A much larger pulse of long period north swell will rapidly build Saturday afternoon and peak Saturday night and Sunday. During the peak, surf along north and exposed east facing shores of most islands will reach High Surf Warning levels, while most west facing shores experience advisory level conditions. Moderate to heavy surges in north facing harbors, mainly at Kahului and Hilo, are anticipated by Saturday and will persist through the weekend. The large swell will also produce combined seas in excess of 10 feet over most waters and will contribute to the need for a SCA. The north swell will steadily decline on Monday and will fade by the middle of next week. Small surf will prevail along south facing shores through early Sunday. Small pulses of south swell are possible late Sunday and Monday and again midweek. && .HFO WATCHES/WARNINGS/ADVISORIES... High Surf Warning until 6 PM HST Sunday for Niihau-Oahu North Shore-Olomana-Maui Windward West-Kauai North-Kauai East-Koolau Windward-Molokai Windward-Molokai North-Maui Central Valley North-Windward Haleakala-Big Island East-Big Island North. High Surf Advisory from 6 AM Saturday to 6 PM HST Sunday for Kauai Leeward-Waianae Coast-Maui Leeward West-Molokai West. Small Craft Advisory until 6 PM HST Sunday for Kauai Northwest Waters-Kauai Windward Waters-Kauai Leeward Waters-Kauai Channel. Small Craft Advisory until 6 PM HST Sunday for Oahu Windward Waters-Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters. Small Craft Advisory from 6 AM Saturday to 6 PM HST Sunday for Oahu Leeward Waters-Kaiwi Channel-Maui County Windward Waters- Big Island Windward Waters. && DISCUSSION...JVC AVIATION...Farris MARINE...Wroe
The national radar mosaic for the moment the first event began.
4 high surf. Local standard time, as filed.
Large surf of 20 to 26 feet created strong currents, beach runup, and hazardous conditions for channels.
Large surf of 10 to 15 feet created strong currents, beach runup, and hazardous conditions for channels.
Large surf of 20 to 26 feet created strong currents, beach runup, and hazardous conditions for channels.
Large surf of 10 to 15 feet created strong currents, beach runup, and hazardous conditions for channels.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Hawaii in 2025Every state in 2025This day in weather historyWarnings in Hawaii, April 2025
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: 1245348, 1245349, 1245350, 1245351.