A concept for measuring water surface backscattering signature and wind over sea using airborne weather radar is discussed. The radar operates in the ground-mapping mode as a scatterometer, in addition to its meteorological and navigation application. An aircraft circular flight is used under such measurement. Recommendations to perform measurement of the water surface backscattering signature along with a sea wind retrieval algorithm are proposed. A simulation study of wind vector estimation is performed. The results obtained show that airborne weather radar can provide reasonable sea wind vector retrieval accuracy.