What weather phenomenon is typically associated with rotor clouds?

Rotor clouds are specifically associated with strong and severe turbulence because they form in the wake of a mountain or obstacle when strong winds interact with the terrain. This interaction creates turbulent eddies and currents in the atmosphere, leading to conditions that can be extremely chaotic for pilots. The presence of rotor clouds indicates that significant vertical wind shear and turbulence are occurring, which can result in dangerous flying conditions.

In contrast, light rain showers, clear and calm conditions, and low humidity levels do not relate to the presence of rotor clouds. Light rain showers typically occur in more stable atmospheric conditions, while clear and calm conditions indicate a lack of turbulence. Low humidity does not contribute to the formation of rotor clouds, as these clouds require adequate moisture and turbulent conditions to develop.