Parameters & indices#sounding#storm-top

EL — Equilibrium Level

Also: EL

At a glance

The altitude where a rising storm parcel finally becomes neutral — roughly, where you see the anvil spread out at the top of a mature storm.

Deep dive

The EL is the upper bound of CAPE: where the parcel path re-crosses the environmental temperature curve from warmer-to-colder. Above the EL, the parcel is negatively buoyant and stops accelerating (though inertia carries it into an overshooting top).

A high EL (10+ km in UK summer, 14+ km in a US plume event) signals a deep moist layer and tall storms. EL temperature correlates loosely with hail potential — very cold ELs give larger hail because stones grow for longer in sub-freezing air.