基于遥感资料的甘肃东南部一次强降水过程分析及预警研究

Using TBB products of FY-2E satellite and radar data，NCEPNCAR reanalysis data, hourly precipitation data of regional stations in Gansu province and upper airsurface observation data, a heavy rainfall process occurred in the southeast of Gansu province from June 19 to June 20, 2013 was analyzed. The results show that the immediate cause of the heavy rain was the MCC formed by a line of convective clouds occurred in the southeast of Gansu connected to the severe convection system originated in central Sichuan moving northeast. The area of TBB≤-52℃ and T-Td≤5℃ when the rain began about 1 or 2 hours was nearly short-time heavy rainfall region. When TBB is lower than -40℃ and the gradient of TBB is lower than 6, heavy rain will take place in these areas. Radar echo intensity which is higher than 40 dBz can be used as warning threshold. Short-time heavy rainfall will occur in the region where the upwind area generated or passed through in 1 or 2 hours.