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Cyclone Ami

Category 3 South Pacific cyclone in 2003

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Through Flood, Landslide and Power outage

Cyclone Ami severely impacted areas of Fiji, primarily causing flooding. Numerous landslides and power outages resulted from the heavy rains. Damage was particularly severe in Labasa, Fiji, where floodwater inundated the entire city. Damage sustained to crops was also severe, especially the sugar cane, where production decreased by 15% due to Ami. In Tonga, damage was not as severe. However, two ships offshore were grounded due to the cyclone. Ami caused F$104.4 million (US$51.2 million) in damages and 17 deaths, primarily on Fiji. Following the deaths and damage, the name "Ami" was later retired.

Meteorological history

On January 9, 2003, the Fiji Meteorological Service (FMS) started to monitor a weak tropical depression, that had developed within a monsoon trough about 800 km (495 mi) to the northwest of Apia, Samoa. Over the next two days as the system moved towards the southwest further development of the depression was inhibited by strong vertical windshear, before during January 11, the vertical windshear decreased and the system started to rapidly develop further. As it developed further the United States Joint Typhoon Warning Center issued a tropical cyclone formation alert on the system, before they designated it as Tropical Cyclone 10P later that day as the 1-minute sustained windspeeds became equivalent to a tropical storm. The FMS subsequently reported six hours later that the depression had developed into a category one tropical cyclone on the Australian tropical cyclone intensity scale, and named it as Ami, while it was located just to the east of the southern Tuvalu island of Niulakita.

Tracking southwest, the storm was named Tropical Cyclone Ami at approximately 0000 UTC on January 12 under favorable upper-level diffluence facilitated by the nearby ridge of high pressure. Influenced by an upper-level trough, Ami slowed in forward movement and turned on a more southerly course. With minimal wind shear and a good outflow pattern, Ami achieved severe tropical cyclone intensity at 0600 UTC on January 13. A poorly defined eye feature became visible on satellite imagery, at which point the storm was situated around 160 mi (260 km) north-northeast of Labasa. The cyclone made landfall on Vanua Levu with a minimum barometric pressure of 960 hPa (28.35 inHg) before subsequently crossing the western tip of Taveuni. Broadly turning toward the southeast, Ami traversed the Lau Islands. While located about 60 miles south of Lakeba – at 0600 UTC on January 14 – the storm reached its peak intensity with 10-minute maximum sustained winds of 90 mph (140 km/h) and a pressure of 950 mbar (28 inHg). At the same time, the JTWC assessed the storm with 1-minute winds of 125 mph (201 km/h).

Accelerating toward the southeast with forward speed reaching 40 mph (64 km/h), Ami began to gradually weaken due to resuming wind shear and increasingly cool waters. The cyclone interacted with a frontal boundary, and in doing so it transitioned to an extratropical cyclone. Ami lost all tropical characteristics by 1200 UTC on January 15, although its remnants continued eastward to a point well south of Rarotonga. On January 14, RSMC Nadi issued their final advisory on Ami and passed the primary warning responsibility for Cyclone Ami to the Wellington Tropical Cyclone Warning Center (TCWC Wellington) as the system moved below 25 °S.

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