Cyclone Wilma (2011)

Severe Tropical Cyclone Wilma

Category 4 severe tropical cyclone (Aus scale)
Category 4 (Saffir–Simpson scale)
Severe Tropical Cyclone Wilma on January 26
Formed	January 19, 2011
Dissipated	January 30, 2011
(Extratropical after January 29, 2011)
Highest winds	10-minute sustained: 185 km/h (115 mph) 1-minute sustained: 215 km/h (130 mph)
Lowest pressure	930 hPa (mbar); 27.46 inHg
Fatalities	3 direct
Damage	$22 million (2011 USD)
Areas affected	American Samoa, Samoa, Tonga, New Zealand
Part of the 2010–11 South Pacific cyclone season

Severe Tropical Cyclone Wilma was a powerful tropical cyclone that affected the Samoan Islands, Tonga and New Zealand. Forming out of a trough of low pressure on January 19, 2011 to the northwest of Fiji, Cyclone Wilma initially tracked eastward towards the Samoan Islands. On January 22, the system took a sharp southward turn, bringing its centre directly over American Samoa the following day. After turning towards the southwest and accelerating, Wilma steadily intensified into a severe tropical cyclone before striking Tonga. The storm reached its peak intensity on January 26 as a Category 4 cyclone with winds of 185 km/h (115 mph) and a barometric pressure of 930 mbar (hPa; 27.46 inHg). Gradually re-curving towards the southeast, Wilma weakened quickly as it moved over cooler sea surface temperatures; by January 28, it was downgraded to a tropical cyclone. Later that day, the storm brushed the North Island of New Zealand before transitioning into an extratropical cyclone.

Throughout Wilma's path, three countries were affected, with New Zealand experiencing the most severe damage. At least three fatalities in American Samoa have been blamed on the storm, two from flooding and one from high seas. In Tonga, "major damage" was reported across the Ha'apai Islands. In New Zealand, several homes were destroyed by the storm and hundreds of people were evacuated. However, there were no reports of fatalities. Torrential rain in the country, exceeding 280 mm (11 in) in some places, triggered 50-year flood events and isolated towns.

Early on January 19, RSMC Nadi reported that Tropical Disturbance 06F had developed, along a trough of low pressure about 665 km (413 mi) to the northeast of Nadi, Fiji. During that day convection surrounding the disturbance gradually became more organized before early the next day, RSMC Nadi reported that it had intensified into a tropical depression. On January 22, The Joint Typhoon Warning Center (JTWC) started monitoring the system as Tropical Cyclone '08P'. Later the same day, RSMC Nadi upgraded Tropical Depression 06F to a tropical cyclone and named it 'Wilma'. Early on January 24, RSMC Nadi further upgraded Wilma to a Category 2 Tropical Cyclone. Late on the same day, RSMC Nadi reported that Wilma had intensified into a Category 3 Severe Tropical Cyclone. Wilma Continued to strengthen and January 26, the RSMC Nadi upgraded it into a Category 4 Severe Tropical Cyclone. Early on January 27, Wilma entered TCWC Wellington's area of responsibility. A few hours later, TCWC Wellington took full responsibility of Wilma, and downgraded it into a Category 3 Severe Tropical Cyclone. Wilma continued to weaken and TCWC Wellington further downgraded it into a tropical cyclone. On January 28, the JTWC, issuing their final warning, reported that the system took a southeast curve along the coast of North Island, New Zealand and started becoming extratropical. A few hours later, the TCWC Wellington, downgraded it into a low, no longer considering it tropical.