Acknowledgements

The author used the whimsically named, but excellent ``Fastest Fourier Transform in the West'' (FFTW) library (Frigo and Johnson, 1998) to perform the Fast Fourier Transform. The work detailed in this paper was partially funded by the National Severe Storms Laboratory, the Federal Aviation Agency and via contract with WeatherData, Inc. The author thanks Marilyn Wolfson and her group at Lincoln Laboratory for pointing out the inability of the transform method to deal with missing data.