Storm types#storm#weak-shear

Pulse storm (air-mass storm)

At a glance

A single-cell summer thunderstorm that blows up, drops a localised hail core or gust, and collapses — all within about 30 minutes.

Deep dive

Pulse storms live in weak-shear, high-CAPE regimes. The updraft ingests its own downdraft within minutes and chokes. Hazards are brief but real: localised hail, microburst winds (40–60 kt), and flash-flood rainfall from slow motion.

Most common on UK summer afternoons under weak synoptic flow — pretty cumulonimbus on the satellite, occasionally a gust front on radar, gone by sunset.