Current measurements revealed that nonlinear internal waves, generated within the Strait of Gibraltar, propagated eastward about 50 km into the western Mediterranean Sea and appeared as energetic packets of 30 minute period waves. The waves had a net eastward transport in the upper layer such that during a ten day period the waves carried one-third of the climatic transport. This partitioning of transport, normally carried by a narrow current, may have altered the strengths of the Atlantic inflow current and the anticyclonic Alboran Sea gyre.