Storm types#linear#wind

Derecho

At a glance

A long-lived, widespread windstorm produced by a fast-moving line of thunderstorms. Think of it as a bow echo that never stops.

Deep dive

A derecho is a convectively driven windstorm with a continuous wind swath of at least 400 km and embedded gusts >33 m/s (65 kt). They're rare in the UK — the 2012 'super derecho' over eastern England is the most-cited example in recent memory.

Typical ingredients: long, straight hodograph in the 0–6 km layer; moderate-to-high CAPE; forward-propagating cold pool; weak CIN downstream so new cells fire at the leading edge. Forecast skill for derechos remains modest — they often under-resolve in operational models.