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Hurricane Iniki

Category 4 Pacific hurricane in 1992

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Through Natural disaster

Iniki caused around $3.1 billion (1992 USD) in damage and seven deaths. This made Iniki, at the time, the costliest natural disaster on record in the state, as well as the third-costliest to hit the U.S. It struck just 18 days after Florida was devastated by Hurricane Andrew, which was the costliest tropical cyclone ever at the time. The Central Pacific Hurricane Center (CPHC) failed to issue tropical cyclone warnings and watches 24 hours in advance. The hurricane destroyed more than 1,400 houses on Kauaʻi and severely damaged more than 5,000. Oʻahu experienced moderate damage from wind and storm surge.


Meteorological history

The origin of Iniki is unclear, but it may have begun as a tropical wave that exited the west African coast on August 18. It moved westward across northern South America and Central America, entering the eastern Pacific Ocean on August 28. On September 5, Tropical Depression Eighteen-E developed from the wave, about 1,700 miles (2,700 km) southwest of the southern tip of the Baja California peninsula, or 1,550 miles (2,490 km) east-southeast of Hilo. Upon its formation, the depression had a ragged area of convection, and the National Hurricane Center anticipated minimal strengthening over the subsequent few days. This was due to the convective structure having poorly defined outflow, or ventilation. Warm sea surface temperatures, 2–5° F (1–3° C) above normal, were considered a positive factor. On September 6, the depression crossed 140° W, entering the area of warning responsibility of the Central Pacific Hurricane Center (CPHC). On that day, the CPHC anticipated that the depression would dissipate within 24 hours, and ceased issuing advisories, but the depression reorganized on the next day, and warnings were reissued. Steered by a subtropical ridge to the north, the depression continued westward, or slightly south of due west. On September 8, the CPHC upgraded the depression to tropical storm status, giving it the name Iniki, which is Hawaiian for a sharp and piercing wind.

Iniki gradually intensified as its track shifted to the north. It moved around the western edge of the subtropical ridge, which was weakening due to an upper-level trough moving eastward from the International Date Line. Typically, the subtropical ridge keeps storms away from the Hawaiian islands. Meanwhile, the usual wind shear that exists around and over the islands that weakens storms as they approach weakened south and west of the ridge, allowing for a favorable environment for intensification. On September 9, Iniki strengthened into a hurricane, and the next day it passed about 300 miles (480 km) south of Ka Lae, the southernmost point of the Big Island of Hawaii. The hurricane slowed and curved toward the north while continuing to intensify. On September 10, a reconnaissance aircraft flew into Iniki, observing sustained winds of 115 mph (185 km/h), which is a major hurricane, or a Category 3 on the Saffir-Simpson scale. The approaching trough caused Iniki to accelerate to the north-northeast toward the western Hawaiian islands.

On September 11, a reconnaissance aircraft observed maximum sustained winds of 145 mph (233 km/h), with gusts to 173 mph (278 km/h), making it a Category 4 hurricane. The flight also observed a minimum barometric pressure of 938 mbar (27.7 inHg), the lowest ever observed in the Central Pacific at the time. Simultaneously, the hurricane was about 130 mi (210 km) southwest of Lihue. Iniki weakened slightly after its peak, and its eye made landfall on the southern coast of Kauai near Waimea with winds of 140 mph (230 km/h), making it the strongest hurricane on record to strike Hawaii. Iniki moved rapidly across the island, and about 40 minutes after landfall, it reemerged into the Pacific Ocean as it accelerated away from the state. The hurricane thereafter weakened, dropping to tropical storm status by September 13. That day, Iniki transitioned into an extratropical cyclone as it integrated with an approaching cold front about halfway between Hawaii and Alaska.

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