Precipitation Evolution in Tropical Cyclones After Landfall

根据美国天气研究计划，飓风预测的几个方面已被确定为高度优先的研究领域。更好地了解和预测飓风登陆后的降雨量是这些高度优先考虑的领域之一。这项研究的主要目标是了解控制飓风登陆后降雨量和分布的机制。具体而言，首席研究员将检查总降雨量、强降雨的面积覆盖、降雨相对于路径的对称性以及降雨类型（对流与非对流）。低槽与飓风相互作用的有无以及飓风的温带过渡是影响登陆后降水演变的重要因素，这些相互作用将包括在研究中。将采用两种主要的方法方法：对大量飓风的总降雨量进行气候学研究，以便确定可能的行为范围；以及极端事件的案例研究。将利用现有的雨量数据进行气候研究，并利用实际多普勒雷达数据（WSR-88D）进行个案研究。国家雷电探测数据将用于提供有关降水性质的额外信息。这项研究的成功完成将有助于更好地了解热带气旋内的降水过程，从而最终更好地预报登陆后的洪水。

Under the U.S. Weather Research Program, several aspects of hurricane prediction have been identified as high priority areas of research. Better understanding and prediction of rainfall from hurricanes after they make landfall is one of these high priority areas. The major goal of this research is to understand the mechanisms that control the amount and distribution of rainfall in hurricanes after landfall. Specifically, the Principal Investigators will examine the total rain volume, the areal coverage of heavy rainfall, the symmetry of rainfall with respect to the track, and the type of rainfall (convective versus nonconvective). The presence or absence of trough interactions with the hurricane and extratropical transition of the hurricane are significant factors in the evolution of precipitation after landfall and these interactions will be included in the study.Two major methodological approaches will be employed: a climatological study of total rainfall in a large number of hurricanes in order to establish the range of possible behavior; and case studies of extreme events. Rainfall estimates will be made using existing raingauge data for the climatological study and operational Doppler radar data (WSR-88D) for the case studies. National Lightning Detection Data will be used to provide additional information about the nature of the precipitation.Successful completion of this research will lead to better understanding of precipitation processes within tropical cyclones, which eventually will result in better forecasts of post landfall flooding.