The analysis of coherent Ku-band radar data measured from the Chesapeake Bay Light Tower as part of the SAXON Experiment in September-October 1988 is discussed. We concentrate on a 20-min data segment collected at an incidence angle of 20¿ for both V--V and H--H polarization. Average Doppler spectra are estimated for each second of the data. These Doppler spectra show a large variation in center frequency and relative power due to the influence of the longwave surface on the backscattered field. The basic assumptions and approximations used in the formulation of a time-dependent scattering model are briefly presented, and concurrent measurements of the longwave surface spectrum at the tower are input into this model in order to calculate the expected mean Doppler spectra. These calculated spectra show very good agreement with the measurements. Implications of the measurements and calculations concerning future experiments and refinements to the model are also discussed. ¿American Geophysical Union 1991