flanking line
area of cumulus congestus or small cumulonimbus that mark an area of widespread updrafts on the edge of strong thunderstorms
en-GB/ˈflæŋkɪŋ ˈlaɪn/
en-US/ˈflæŋkɪŋ ˈlaɪn/
area of cumulus congestus or small cumulonimbus that mark an area of widespread updrafts on the edge of strong thunderstorms