Level of Free Convection (m AGL)

The LFC (Level of Free Convection) is the level at which a lifted parcel begins a free acceleration upward to the equilibrium level. Recent preliminary research suggests that tornadoes become more likely in supercells when LFC heights are less than 2000-m above ground level.

The EL (equilibrium level) is the level at which a lifted parcel becomes cooler than the environmental temperature and is no longer buoyant (i.e., "unstable" ). The EL is used primarily to estimate the height of a thunderstorm anvil.

The height difference between this parameter and the LCL is important when determining convection initiation. The smaller the difference between the LFC and the LCL, the more likely deep convection becomes. The LFC-LCL difference is similar to CIN (convective inhibition).