Researchers have investigated different techniques to improve damping for transient stability events. Off-line security analysis and day-ahead studies are scenarios where unacceptable damping levels for oscillatory instabilities may be detected. One type of correction to improve damping is to re-dispatch generation. In this paper, a new prediction method will use data from a conventional transient stability simulation to predict transient performance over an abbreviated observation window. Damping levels will be calculated using a simple iterative technique and the Stability Output Fourier Transformation method. If damping levels are found to be insufficiently small, improvement will be demonstrated after generation has been re-dispatched. Several examples will show that the new prediction method along with the damping calculation technique can estimate transient stability performance before and after implementing a re-dispatching scheme to improve damping.