Altostratus Mamma

Above: Altostratus Mamma

Altostratus Mamma

Altostratus mamma is a type of cloud which has circular protrusions from the base of the cloud, giving the impression of overhanging breasts. These clouds normally form in an environment of strong shear forces, which means that they can be particularly dangerous for aviators since they may cause a lot of turbulence.

What height are altostratus mamma clouds found?

Altostratus mamma normally from at an altitude of around 6,500 and 23,000 feet (2,000 to 7,000m). This is considered an average altitude for clouds, and this is why they are termed as middle clouds when classifying the clouds in general.

Classification of altostratus mamma clouds

Altostratus mamma are middle genus clouds.

How are altostratus mamma clouds formed?

These clouds are formed by lifting of a large air mass to the altitude of middle clouds, and then condensation occurs. These clouds typically contain crystals or water droplets. The size of these particles (crystals or droplets) normally increases with increasing altitude, meaning that the higher the cloud the denser it will look. Usually, when ice crystals form in these types of clouds, they take on a hexagonal shape at the top, but are conglomerated at the bottom of the cloud.

What do altostratus mamma clouds look like?

Altostratus mamma are clouds which can be identified on the basis of the pouch-like protrusions at the base of the clouds. In Latin, the word ‘mamma’ means breast, and the altostratus mamma clouds have been named as such because of the fact that looked at from below, the underside of these clouds seem to look like hanging breasts.

The protrusions from the base of the clouds can have different morphology depending on different factors. They can either look smooth, rugged or even lumpy. There are also various other morphological characteristics of the mammatous clouds. For instance:

  • They may clump together forming a single cluster that stretches on for miles
  • They can be organized into a single line
  • The lobes may be of the same or unequal size


One lobe normally has an average diameter of around 1 to 3Km and a length of 0.5Km on average. In terms of duration, it’s common to have the lobes lasting for around 10 minutes, but one cluster can last for as long as 15 minutes to several hours. Altostratus mamma are normally composed of materials such as ice, but it’s not uncommon to find them containing ice and water or just water entirely.

How common are altostratus mamma clouds?

Altostratus mamma clouds can be seen in any part of the world. As with most altostratus clouds, they are more common in regions experiencing wind shear forces.

Where can I see altostratus mamma clouds?

Altostratus mamma clouds can be seen worldwide. They are common in regions that normally experience lots of rain, since these clouds can actually be used to predict heavy rain. For this reason, it’s hard to see altostratus mamma clouds in areas which are principally arid, such as in the desserts and similar climates. Most of the time, altostratus mamma clouds can be seen early in the day, so the best time to see them clearly would be at dawn where they can look beautiful.

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