Space-based observations of precipitation offer great promise for improved understanding and quantitative estimation of tropical cyclone rainfall. The fulfillment of this promise will play a significant role in addressing key National Aeronautics and Space Administration (NASA) Earth Science research goals of monitoring global precipitation changes, explaining correlations of these possible changes to global climate change, and improving weather forecasting. This promise will also contribute to the U.S. Weather Research Program goal of accurate 72-h prediction of landfalling hurricane rainfall.

To identify the potential of spaceborne microwave observations to map tropical cyclone (TC) rainfall, a study of TC precipitation type has been undertaken using microwave observations from both spaceborne and airborne instrumentation. Tropical cyclones sampled by the Tropical Rainfall Measuring Mission (TRMM) and the ER-2 high altitude aircraft as part of the Third Convection And Moisture EXperiment (CAMEX-3) in 1998 and the Fourth Convection And Moisture Experiment (CAMEX-4) in 2001 form the basis of this study. Highlights of complimentary TRMM and CAMEX-3 observations of Hurricane Bonnie will be discussed.