Plain English Meaning
A line of thunderstorms that lines up in a row even though there is no warm or cold front in the area. The storms group together for other reasons, like air piling up where winds meet or terrain forcing the air upward.
Full Definition
Long, narrow lines or zones of thunderstorms that form away from any weather front, typically driven by local instability, terrain effects, or converging surface winds rather than the lifting action of a frontal boundary.
Context Anchor
Seen in weather discussions, cloud descriptions, and preflight planning when cloud areas are arranged in lines but are not tied to a front.