Stratus cloud classified as pannus clouds. Stratus only has one mutatus mother cloud. Stratus stratocumulomutatus clouds occur when stratocumulus opacus patches fuse to create a stratiform layer. Stratus clouds don't produce accessory clouds, but a supplementary feature praecipitatio is derived from Latin, which means "precipitation". Stratus clouds are too low to produce virga, or rain shears that evaporate before reaching the ground. A stratus cloud can form from stratocumulus spreading out under an inversion, indicating a continuation of prolonged cloudy weather with drizzle for several hours and then an improvement as it breaks into stratocumulus. Stratus clouds can persist for days in
Mushroom cloud Layering of humidity in the atmosphere, responsible for the appearance of the condensation rings as opposed to a spherical cloud, also influences the shape of the condensation artifacts along the stem of the mushroom cloud, as the updraft causes laminar flow. The same effect above the top of the cloud, where the expansion of the rising cloud pushes a layer of warm, humid, low-altitude air upwards into cold, high-altitude air, first causes the condensation of water vapour out of the air and then causes the resulting droplets to freeze, forming "ice caps" (or "icecaps"), similar in both appearance and mechanism