Arakawa was the central figure in formulating convective quasi-equilibrium, a postulate for the interaction of moist convection with large-scale dynamics, in the early 1970s. This has become a key ingredient of convective parameterizations in climate and weather models and in much theory for tropical dynamics. With recent satellite data for moisture and convection, and analysis tools borrowed from statistical physics, it proves possible to make a link between quasi-equilibrium and critical phenomena occurring at continuous phase transitions. Arakawa's vision seems all the more prescient when rephrased in these terms---especially considering that his formulation predates many of the statistical physics developments, like self-organized criticality, by over a decade.