NAM

Convective Available Potential Energy (CAPE)

Convective Available Potential Energy or CAPE refers to the potential energy (measured in Joules) an air parcel would have at the Level of Free Convection (LFC) if allowed to rise to the Equilibrium Level (EL). Large amounts of CAPE indicate that an air parcel would be much warmer than its surounding environment and therefore, very buoyant. Also displayed on this chart is Convective Inhibition (CIN) (hashed in blue/purple) which prevents a parcel from reaching the LFC. Surface heating or mechanical lifting is required for the parcel to be able to reach the LFC. In many instances, severe weather simply cannot develop because of low-level stability which prevents parcels at the surface from becoming buoyant, despite substantial CAPE.