instability

Referring to the atmosphere, it represents a state of non-hydrostatic equilibrium. When there is atmospheric instability, any air bubble forced to move slightly in the vertical tends to rise freely, without restraint, insofar as it constantly encounters air denser than the air it contains. The presence of air colder than normal in the mid and upper levels of the troposphere favors rising air motions and the formation of vertically developed clouds that sometimes culminate in storms. A significant degree of atmospheric instability is necessary for them to be able to form. Different mechanical and thermal mechanisms also contribute to this, such as surface wind convergence, orographic forcing, or ground heating from sunlight.