Radiatus

Radiatus describes a specific cloud variety characterized by parallel bands that appear to radiate from a point on the horizon, or from several points. This apparent convergence is an effect of perspective, as the bands are actually nearly parallel.

Radiatus can occur with cloud types such as Altocumulus, Cirrus, and Altostratus. The "radiatus" feature is a supplementary feature, meaning it is added to the basic cloud type name (e.g., Altocumulus radiatus).

The apparent radiating pattern is most noticeable when the clouds are viewed at a low angle near the horizon. As the viewing angle increases (looking higher in the sky), the radiating effect becomes less pronounced, and the parallel bands may appear more uniform. The direction from which the clouds appear to radiate can sometimes be used to infer wind direction at the altitude where the clouds are forming.