The author thanks NCEP/EMC for their help in running the GFS and in providing the computer resources to make the study possible and Steve Lord and James Franklin for helpful discussions. Nelsie Ramos provided much of the graphics in the Frances and Ophelia cases and engaged in many fruitful discussions. Sharan Majumdar and Brian Etherton provided the ETKF guidance, and Carolyn Reynolds provided the SV target guidance. Bob Kohler and Bill Barry provided computer support and guidance at HRD. The author also thanks the NOAA/Aircraft Operations Center (AOC) flight crews and dropwindsonde operators, Jack Parrish, the AOC G-IV project manager, and HRD personnel who participated in the flights. Jason Dunion, Mike Jankulak, Robert Rogers, and two anonymous reviewers provided helpful comments on an earlier version of this manuscript.
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