Aerial survey data are used to reconstruct the flow velocities and slope spectra for an agitated surface in the region of a frontal zone characterized by large horizontal flow velocity gradients. By means of the spectral equation for wave action balance in the collision-free approximation, the spatial inhomogeneity in the wind-wave field is calculated at the boundary between the two flows simulating a frontal zone. In this case, quantitative agreement is obtained between the calculated and observed positions for the spectral maxima, and qualitative agreement is obtained between the shapes of the spectra. -from Authors