Precipitation Evolution in Tropical Cyclones After Landfall

Suny At Albany, Albany NY

Investigators

Abstract

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.