The effect on radar detection of the shape of the Doppler spectrum of windblown vegetated ground clutter is analyzed. An extensive experimental campaign carried out by MIT Lincoln Laboratory showed the shape of the windblown clutter Doppler spectrum to be exponential, in contrast to two other widely-used spectral models (i.e., Gaussian and power-law). The detection performance of two classes of surveillance radar, ground-based and Airborne Early Warning, is evaluated and compared against windblown ground clutter using the three above-mentioned Doppler spectral shapes. The analysis is first done with closed-form equations, and subsequently validated using a set of measured clutter data. It is demonstrated that the exponentially shaped Doppler spectrum should be used as the reference to model windblown ground clutter for the prediction of radar detection performance.