An elongated cloud system, roughly resembling a leaf, visible in satellite images in the early stages of the formation of a depression. It arises within the air of the warm conveyor belt. The poleward edge of the leaf cloud has the shape of a flattened letter ‘S’, and the western edge often shows a notch, which will later develop into the dry slot. With further cyclogenesis, the pattern becomes a comma cloud.
Subjects: Meteorology and Climatology.