A large northeast swell brought surf up to eighteen feet to the east facing coasts of the islands. This led to some coastal flooding and debris flows for portions of the coastlines.
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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 northeast swell brought surf up to eighteen feet to the east facing coasts of the islands. This led to some coastal flooding and debris flows for portions of the coastlines. Several beach parks were also closed.
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 Dec 17, 9:00 PM HST, 5 hours earlier.
Area Forecast Discussion National Weather Service Honolulu HI 900 PM HST Sun Dec 17 2023 .SYNOPSIS... The high pressure ridge north of the islands will build through Wednesday, strengthening the trade wind speeds into the breezy to locally windy range. Showers remain in the forecast with the highest coverage expected during the overnight and early morning hours. Extensive high cirrus clouds will continue through much of this week due to a subtropical jet stream in the upper levels. Breezy trade winds continue into the weekend. && .DISCUSSION... Satellite imagery this evening shows a large band of cirrus clouds over the Hawaii region caused by a subtropical jet stream as shown by the transverse banding on the water vapor imagery. A narrow upper level trough (also known as the Tropical Upper Tropospheric Trough or T.U.T.T.) is shown north through west of the island chain. Weak TUTT lows within this upper level trough and divergence aloft within the subtropical jet stream will help to produce showers across the area through much of this week. A strong high pressure system will build just north of the Hawaiian Islands through the week, ramping up trade winds into the breezy to locally windy range from Tuesday through Thursday. Wind speeds will remain at breezy levels on Friday as another high center moves into the Central Pacific basin and merges with the existing high. This combined high pressure system will then drift eastward away from the state on Saturday and Sunday with decreasing wind trends to more moderate speeds just in time for the weekend. The island weather pattern will remain fairly wet this week with passing showers day and night for all islands through at least Thursday. This enhanced shower activity is caused by the upper level divergence associated with the jet stream and the southeastern side of the upper trough. By Friday and Saturday the axis of this upper trough will drift over the islands, stronger subsidence (downward vertical motions) along the trough axis and an upper level ridge building in from the west will add some stability over the Hawaii region and reduce shower coverage by this weekend. && .AVIATION... Locally breezy trade winds will continue through tomorrow, focusing light showers along windward areas. Periods of MVFR conditions or lower will be possible in these showers, mostly overnight into the early morning hours when better shower coverage is expected. Otherwise, VFR conditions will prevail. No AIRMETs in effect. && .MARINE... Surface high pressure far north of the Hawaiian Islands will remain nearly stationary through the middle of the week before weakening. Winds look to ramp up Monday and remain near fresh to locally near gale force Tuesday and Wednesday. Winds look to slightly weaken Thursday into the end of the week. Rough seas are expected to continue over most Hawaiian waters due to a combination of strong trade winds, a mix of northeast wind waves and a large long-period northeast swell. A combination of winds and rough seas will continue to support Small Craft Advisory (SCA) over exposed waters and channels through the first half of this week. The SCA coverage area will likely expand from Monday through Wednesday. A large, long-period north to northeast swell arriving from a broad gale centered around 1600 nm northeast of the state will support warning level surf for east facing shores late tonight into Monday. A High Surf Warning (HSW) has been issued for all east facing shores through Monday. Due to the direction of the swell, impacts to low-lying coastal areas and roadways are expected especially coinciding with the peak early morning high tide. A smaller north-northwest medium period swell filled in today keeping surf along north and west facing shores elevated. Late Monday into Tuesday a small northwest swell will arrive before another larger northwest swell looks to build in near High Surf Advisory levels along north facing shores Thursday to Friday. A small long period south (180-210 degree) swell will build into the region with a slight bump in south shore surf activity lasting into Tuesday. && .HFO WATCHES/WARNINGS/ADVISORIES... High Surf Warning until 6 PM HST Monday for east facing shores of Kauai, Oahu, Molokai, Maui and the Big Island. Small Craft Advisory until 6 AM HST Tuesday for all windward waters, all channels, and Maalaea Bay. && DISCUSSION...Bohlin AVIATION...Farris MARINE...Shigesato
The national radar mosaic for the moment the first event began.
1 high surf. Local standard time, as filed.
Bayfront Highway in Hilo was closed due to high surf and debris on the roadway.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Hawaii in 2023Every state in 2023This day in weather historyWarnings in Hawaii, December 2023
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: 1147682.