Analysis of a Tornado in Outside-Region of The Super Typhoon 'Sepat' in 2007

When the super typhoon 'Sepat' was close to off the Fujian coastline at the night of August 18,2007,a related tornado was derived in Longgang town,Cangnan county of Wenzhou region,about 300 km away in the direction of the typhoon moving forward at 23:07~23:20 BST.when detecting tornadoes and Tornados causing damages,which is a above F2 category one and is associated with the super cells using the Doppler radar,the close attention should be paid to carefully analyze the reflectance factor,vertical wind shear and storm-relative radial speed,the mesocyclone formation on lower levels,the merger of more microvortex and the local terrain features,apart from the synoptic background condition,e.g.,unsteady weather process and vertical wind shear.