@Phileas-Fogg You think that the Radar layer should predict future rains. But a radar is NOT a tool that predicts the future. Radars that detect and track the flight of planes or the speed of cars are not able to predict the future trajectory of these mobiles. The hour that the Radar layer visualizes in the future is only an extrapolation of the previous hour, it is NOT a real forecast. As @Wheats says, look at the Rain, thunder layer and preferably as predicted by the different weather models available in your area.