Diagnostic Analysis of Reasons for Intensity Weakening Rapidly around Landfall of Typhoon No. 0601

In this paper,by using the NCEP daily reanalysis data,the causes for typhoon Chanchu (0601) suddenly weakening are examined.The results show that the main reasons for typhoon Chanchu weakening rapidly around landfall are that the divergence area appears in the west side of typhoon center at low levels and convergence center appears at 150—100 hPa,which makes the structure of divergence field destroyed. In addition,the temperature of the sea surface which the typhoon will pass over would decrease, the warm structure of typhoon is broken up due to the intrusion of dry and cold air advection,and precipitable water vapor of air column also decreases.