Analysis of a Strong Tornado in the Outer-Region of the Super Typhoon "Sepat" in 2007

When the super strong typhoon Sepat came immediately close to the Fujian coastline on the night of August 18, 2007 (coded as 0709 in Chinese convention), a vigorous tornado was derived from the typhoon at 2307~2320 BST that appeared at the Longgang town, Cangnan county of the Wenzhou region about 300 km away in the forward direction of the typhoon, damaging heavily the life and properties of the inhabitants. Through the analysis of the situation for the tornado and composite reflectivity, vertical wind shear and the storm-relative radial velocity from Doppler observations some typical properties are revealed of the destructive tornado, together with such localized characteristics of the tornado investigated as peninsular topographic effect, land – sea thermal contrast as well as a network of densely distributed rivers that produce local dynamic and thermal effects to intensify the derived tornado.