Definition
A vertical temperature lapse rate in the atmosphere that is greater than the dry adiabatic lapse rate of approximately 3 degrees Celsius per 1,000 feet. When the actual air temperature drops faster with altitude than dry adiabatic cooling would predict, the layer is highly unstable and prone to strong vertical air movement.
Plain English
It means the air is getting colder with height faster than normal, which makes the air unstable and likely to rise rapidly, often producing turbulence, thermals, or thunderstorms.
Context Anchor
Seen in aviation weather discussions about atmospheric stability, surface heating, thermals, and low-level turbulence.
Derivation
Super' comes from Latin meaning 'above' or 'beyond.' 'Adiabatic' comes from Greek 'adiabatos,' meaning 'not passable' -- referring to a process where no heat passes in or out. So 'superadiabatic' literally means 'beyond the adiabatic rate' -- the air is cooling with altitude faster than the standard adiabatic process alone would produce.
Why Pilots Care
Signals highly unstable air that can produce strong updrafts, turbulence, and rapid thunderstorm development.
Grounding Statement
Picture a sun-baked desert runway on a hot afternoon: the surface heats the air above it intensely, so temperature drops off very quickly with height -- that lower layer is superadiabatic, and it bubbles upward as thermals.
Intuition Check
Do not read “super” as meaning “better” or “safer.” Here it means the temperature drop with height is steeper than the dry adiabatic rate, which usually points to unstable air.
Example Sentence 1
The afternoon sounding showed a superadiabatic lapse rate in the lowest 2,000 feet, which explained the rough ride on departure.
Example Sentence 2
During preflight the briefer noted superadiabatic conditions below 5,000 feet, prompting us to watch for turbulence on climb-out.