Key point about CIRRUS clouds, that make them different from other clouds. They are ICE clouds, not water-vapor clouds. Although obviously some super-cooled water vapor has to be there/get there in the beginning to freeze into ice. Being formed of ice crystals rather than water drops/vapor means they may follow different "rules" than other clouds. They can form even when the local humidity is low - aglomerating invisibly small amounts of water vapor (gas) into visible shapes. They form at higher altitudes than other clouds (although "higher" is relative - on cold days as low as 16000 feet.) They do not usually "precipitate out" as rain or snow, thus they are often "fair-weather" clouds - although they can also form and trail out from the super-cooled tops of Cbs or other bad weather.
Bottom line, as previously mentioned - cirrus clouds do not cause turbulence. They can be
formed by turbulence and convection. Because of their longer-lasting nature, they may outlive the turbulence (if any) that formed them, and thus they are not necessarily a reliable indicator of the presence of current turbulence. However, they can increase the temperature of the air layer below them
Beyond that, we get into the physics of water phases (triple points, critical pressures/temperatures, specific heats, latent heats, phase changes, enthalpy of vaporization) that go far beyond "weather" per se. And my knowledge...
