Comparative Analysis of Continuous Rainstorm in Sichuan Basin in 2013

Based on NCEP 1°×1°reanalyzed data、Sichuan meteorological observation stations data, in the way of combining synoptic meteorology and dynamic diagnostics, the continuous rainstorm and flood disasters during the period of 18th ~ 20th June, 29 th June ~ 2nd July, 8th ~ 11th July in 2013 are compared and analyzed. In 29th June ~ 2nd July, 8th ~ 11th July in 2013, daily rainfall amount broke history meteorological record of Sichuan province. Discussed of formation mechanism of the basin rainfall and comparative analyzed of the similarities and differences of persistent heavy rainfall. The result show that, the one of the key for basin persistent rainstorm weather was generated under the favorable “high east and low west”rainfall situation, the stable large scale circulation background and the stable mesoscale system provide favorable background to the continuous heavy rain. There is stable low-level jet near rainstorm area is important to rainfall duration. Energy condition of the middle level is an important concern in the continuous heavy rain. Vertical upward flow exists in long time which results in a long life of the convective system. The cold air flow is beneficial to heavy rain to continuous.