This research was supported by Office of Naval Research Grant N000149810599 and the National Science Foundation through Grant ATM9900671. The authors would like to thank Dr. Lloyd Shapiro, Dr. Michael Reeder, David Vollaro, and two anonymous reviewers for their useful comments. The first author would like to thank Cathy Smith of the University of Colorado for her assistance in obtaining the OLR data. The GOES Precipitation Index dataset is available via anonymous ftp at ftp://daac.gsfc.nasa.gov/data/hydrology/precip/arkin/gpcp_gpi/. The CPC Merged Analysis of Precipitation is available via anonymous ftp at ftp.cdc.noaa.gov. The Global Precipitation Climatology Project version 1c satellite–gauge precipitation product (Huffman et al. 1995) is available via anonymous ftp at ftp://daac.gsfc.nasa.gov/data/hydrology/precip/gpcp.
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