Flash floods are major meteorological disasters which occur around the globe. Understanding of this phenomenon is a challenging problem because it is necessary to understand both complex dynamic and microphysical processes at scales of motion that are smaller than typically measured by conventional weather networks. This scale of motion is termed storm-scale or mesoscale by meteorologists. The National Science Council of Taiwan established a Multiple Hazards Mitigation Project whose meteorological component focussed on improving flash flood predictions. A major field project, entitled the Taiwan Area Mesoscale Experiment (TAMEX), was held in the Spring of 1987. The project was a joint effort of various Taiwanese agencies with participation from the National Oceanic and Atmospheric Administration and the National Science Foundation (NSF). The scientific goals were to study the mesoscale systems that form on a quasi-stationary and consistent feature known as the Mei-Yu front and cause the heavy rains known as the "plum rains". Under a previous award from NSF the Principal Investigator participated in the field phase of the TAMEX and began analysis of the data. Preliminary results indicate that the mechanisms important for the formation, intensification and maintenance of the Mei-Yu front may be somewhat different than previously thought. Using aircraft, radar, surface and upper air data, the Principal Investigator will continue his diagnostic studies of the structure of the frontal systems and the severe rain events that they spawn. //
