Clouds rarely form in the stratosphere but when they do, they are sparkly and rainbow-colored.
Nacreous clouds, or ice polar stratospheric clouds, are the only cloud type that can form in the stratosphere and occur over polar regions.
Cloud formation typically occurs in the troposphere which is anywhere from ground level to 33,000 feet depending on latitude and season. Then it is the stratosphere. The stratosphere is usually very dry with little water vapor and weather. Storms can sometimes push moisture higher into the stratosphere to aid in cloud formation.
