The paper presents a study of detonation propagation in supersonic crossflows over a range of Mach numbers. The work is focused on characterizing the detonation wave dependence on the supersonic cross-stream Mach number. A high-enthalpy combustor is used to provide continuous premixed supersonic crossflows that interact with an orthogonal detonation provided by a miniaturized detonation tube. The detonation wave propagation and interaction are characterized for various degrees of nozzle overexpansion driven by change in stagnation pressures. High speed Schlieren imaging is used to visualize the differences in propagating mechanisms for the detonation wave at each Mach number.