Storm types#linear#wind
Squall line
At a glance
A long line of thunderstorms, all sharing a single gust front. Expect damaging wind and brief heavy rain as it passes — tornadoes are possible but rare.
Deep dive
Squall lines form when individual cells merge along a convergence boundary (often a cold front) under moderate deep-layer shear. The leading edge is a density-current gust front; behind it, a rear-inflow jet descends and accelerates outflow winds toward the line.
Embedded QLCS tornadoes occur at kinks and mesovortices along the leading edge — short-lived but often not well warned because radar scans can miss them between volume scans.