Fast-response Pressure Sensitive Paint (PSP) measurements were performed on hemispherical models at transonic flow speeds. Both Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) were used to analyze the spatially and temporally resolved data. POD was used to isolate the dominant behavior in the data and isolate the dominant frequencies by looking at the temporal coefficient spectra. DMD was then used to further investigate specific frequencies. At St = 0.15-0.2, previously investigated "wake breathing" and "wake shifting" modes were found. These modes represent large spanwise symmetric and antisymmetric structures, respectively. Further, at St = 1 and St = 2, DMD showed that the wake of the turret was dominated by smaller convecting structures. The DMD modes were used to estimate the convective velocity in the wake, which was found to be relatively constant across various Strouhal Numbers.
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