Fig. 4: Comparisons of observed rainband propagations with gravity wave (GW) and vortex Rossby wave (VRW) phase velocities.

a Scatterplot of the observed radial propagation velocities vs. the theoretically predicted GW phase velocities for all identified outer TCR cases. b Scatterplot of the observed radial propagation velocities vs. the theoretically predicted VRW radial phase velocities for all identified outer TCR cases. c Same as in (b) but showing the observed tangential propagation velocities vs. the theoretically predicted VRW tangential phase velocities. In each panel, the diagonal line representing perfect agreement between the observational and theoretical propagation velocities is also indicated for reference. Source data are provided as a Source Data file.