Summary of SW Pacific TC activity for the 2010 -11 season

The tropical cyclone season for 2010–11 has now closed.

The tropical cyclone season for 2010–11 has now closed. The ICU forecast for this season inidcated normal or above normal tropical cyclone (TC) activity for most islands west of the International Date Line in the southwest Pacific, with reduced activity east of the International Date Line due to La Niña conditions in the equatorial and tropical Pacific. A total of nine to 12 named TCs were forecast for the southwest Pacific (between 135°E to 120°W) for the period November 2010 through April 2010.

The action during this TC season began in late December with the formation of TC Tasha and concluded in late March with TC Bune. A total of nine TCs occurred in the region, which was consistent with the number of predicted storms based on the ICU analogue forecast. Five cyclones reached at least Category 3, and three systems reached at least Category 4, with mean wind speeds of at least 64 knots or 118 km/h. This activity was also in line with the prediction of at least three storms reaching Category 3 status and at least one storm reaching Category 4 strength. There were more numerous TCs during the early part of the season, with peak activity occuring in January which had five named storms. Several tropical depressions also formed late in the season; however, none of them developed into a named storm. Damages associated with TC activity for the 2010–11 season are estimated to have exceeded at least $3.5 billion USD, with a total of four reported fatalities.

ICU forecasts indicated an increased risk of TCs impacting island nations surrounding the Coral Sea and to the southwest of Fiji. New Zealand was also at higher risk of experiencing an ex-tropical cyclone interaction this season. The distribution of TC activity was certaintly in line with expectations, with six ex-tropical cyclones entering the New Zealand sector (some having greater impacts than others). Australia was significantly affected by the strongest event of the season when TC Yasi made landfall in Queensland on 3 February. Yasi is esitmated as the second costliest TC in Australian history. Additional information about the 2010–11 season will be hightlighted in forthcoming ICU special interest articles.