Estimation of Hurricane Isabel's rainfall using the TRMM-based Multi-Satellite Precipitation Analysis (MPA) (Invited Presentation)

A TRMM-based Multi-Satellite Precipitation Analysis (MPA) technique is being used to quantify rainfall produced by tropical cyclones while at sea and during landfall. The algorithm generates three-hourly estimates from merged microwave-infrared at 0.25 degree grid resolution. In addition, the study seeks to better understand how the environment and storm-scale characteristics influence the magnitude and distribution of tropical cyclone rains. In the case of Hurricane Isabel, we present temporal trends of rainfall intensity, rain volume and rainfall asymmetry throughout the storm lifecycle. An attempt is made to partition the rains among convective and stratiform contributions. The goal is to illustrate how rainfall volume and intensity are related to factors such as speed of storm motion, circulation strength and inner core intensity - all of which showed dramatic changes throughout Isabel’s complex evolution.