The purpose of this paper is to provide insight into how unsteady ow temperature aects the wall temperature of test articles exposed to convective heating. To this end, a simplied analytical correlation is derived that allows the determination of wall temperature uctuation amplitude in the case of an unsteady freestream. Stagnation point ows with oscillating freestream temperature are analysed applying self-similar boundary layer theory. The correlation reveals that the problem is fully described by two non-dimensional parameters: the ratio of uid and solid thermal eusivities, and the ratio √ Sr Pr Re/Nu of Strouhal, Prandtl, Reynolds, and Nusselt numbers. Numerical conjugate heat transfer simulations are performed for a solid test article subjected to convective heating. The derived analytical correlation agrees well with simulation results, spanning ten orders of magnitude in wall-to-freestream temperature amplitude ratio, with maximum discrepancies of 35%. Deviations from theory occur for low frequencies where the wall temperature of the solid medium undergoes signicant temperature changes. Experimental measurements of an unsteady plasma freestream are analysed, predicting wall-temperature uctuations of test articles of dierent sizes. High frequency content is shown to have little inuence, while low frequencies contribute most to wall temperature uctuations. Small sample sizes are shown to suer from much larger wall-temperature uctuation amplitudes, and high-density ow conditions are more severely aected. The derived theory can be applied to aid in both design and analysis of unsteady convective heating experiments.