Extraction of the axi-symmetric part of a hurricane vortex from high-frequency aircraft observations

"A key step in the new system1 built recently to improve the symmetric initialization of the MFM (Movable-area Fine-mesh Model) is the development of axi-symmetric information about the hurricane vortex from ASDL (Aircraft Satellite Data Link) data sets. The problem simply stated is the determination of a radial profile of tangential wind speed and temperature from asynoptic aircraft observations taken every minute over a several hour period for input to the analysis step. In this note this preprocessing is outlined in detail beginning with raw data and flight plan specifications followed by descriptions of error checking, recoordinization to account for asynopticities, and azimuthal and radial averaging. In addition, criteria are laid out at each stage for the continuation of data processing---only data sets with certain minimal spatial coverage are considered acceptable for spatial averaging. A simplified flow diagram of the entire system is included for reference in Fig. 1"--Introduction. Robert E. Livezey. "October 1979." "This is an unreviewed manuscript, primarily intended for informal exchange of information among NMC staff members." System requirements: Adobe Acrobat Reader. 1979 NWS (National Weather Service) NCEP (National Centers for Environmental Prediction) Library Public Domain 2285