Sometimes convection at high altitudes produces another form of cirrus called cirrocumulus, a pattern of small cloud tufts which include droplets of supercooled water.

• 所以清晨当太阳还没有升到地平线上或傍晚太阳已下山后，光线都会照到这种孤悬高空而无云影的卷云上，经过散射后，显现出漂亮的红色或橘红色的霞象，在夏日的晴空中十分常见。