Catalina Eddy is an atmospheric vortex with a counterclockwise rotation pattern occurring over the bight of Southern California. It is caused by the interaction between the atmospheric pressure gradients and coastal topography of the region. Catalina Eddy has a profound impact on local weather by bringing onshore moist and cool marine air. Due to sparse ground observations, the detailed wind pattern of Catalina Eddy has not been well measured. However, the recently launched NASA QuikSCAT satellite measures ocean surface winds on high spatial resolutions, providing a unique capability to capture complete wind circulation of these small-scale wind eddies. In this paper, we will present case studies by using QuikSCAT winds, atmospheric soundings, buoy measurements, and an operational mesoscale model. We will discuss the origin and evolution of the Catalina Eddy, and address the improvement and limitation of model forecast.