1. Nacreous Clouds
rare clouds, sometimes called mother-of-pearl clouds, are 15 – 25km (9
-16 miles) high in the stratosphere and well above tropospheric clouds.
They have iridescent colours but are higher and much rarer than ordinary
iridescent clouds. They are seen mostly but not exclusively in polar
regions and in winter at high latitudes, Scandinavia, Alaska, Northern
Canada. Lower level iridescent clouds can be seen anywhere.
clouds shine brightly in high altitude sunlight up to two hours after
ground level sunset or before dawn. Their unbelievably bright iridescent
colours and slow movement relative to any lower clouds make them an
unmistakable and unforgettable sight.
2. Mammatus Clouds
Mammatus are pouch-like cloud structures and a rare example of clouds in sinking air.
very ominous in appearance, mammatus clouds are harmless and do not
mean that a tornado is about to form – a commonly held misconception. In
fact, mammatus are usually seen after the worst of a thunderstorm has
3. Altocumulus Castelanus
Also known as jellyfish clouds due to their jellyfish-like appearance.
formed around 17,000 ft due to when the rush of moist air comes from
the Gulf Stream and gets trapped between layers of dry air. The top of
the cloud rises into a jellyfish shape and long tentacles known as
“trailing virga” form from rain drops that have evaporated.
4. Noctilucent Clouds
Clouds or Polar Mesopheric Clouds: This is an extroadinarily rare cloud
formation that occurs out on the verge of space between 82km to 102 km
from the earth’s surface.
clouds appear to be luminous yet they reflect the sunlight from the
other side of the earth at night, giving them a glowing appearance
5. Mushroom Clouds
mushroom cloud is a distinctive mushroom-shaped cloud of smoke,
condensed water vapor, or debris resulting from a very large explosion.
They are most commonly associated with nuclear explosions, but any
sufficiently large blast will produce the same sort of effect.
Volcano eruptions and impact events can produce natural mushroom clouds.
Mushroom cloudsorm as a result of the sudden formation of a large
mass of hot low-density gases near the ground creating a Rayleigh-Taylor
instability. The mass of gas rises rapidly, resulting in turbulent
vortices curling downward around its edges and drawing up a column of
additional smoke and debris in the centre to form its “stem”. The mass
of gas eventually reaches an altitude where it is no longer less dense
than the surrounding air and disperses, the debris drawn upward from the
ground scattering and drifting back down.
6. Cirrus Kelvin-Helmholtz
as a slender, horizontal spiral of cloud, cirrus Kelvin-Helmholtz is
one of the most distinctive cloud formations. However, it tends to
dissipate only a minute or two after forming and, as a result, is rarely
Average height is around 16,500 ft.
7. Lenticular Clouds
clouds, technically known as altocumulus standing lenticularis, are
stationary lens-shaped clouds that form at high altitudes, normally
aligned at right-angles to the wind direction.
stable moist air flows over a mountain or a range of mountains, a
series of large-scale standing waves may form on the downwind side.
Lenticular clouds sometimes form at the crests of these waves. Under
certain conditions, long strings of lenticular clouds can form, creating
a formation known as a wave cloud.
8. Roll CloudsA
roll cloud is a low, horizontal tube-shaped arcus cloud associated with
a thunderstorm gust front, or sometimes a cold front. Roll clouds can
also be a sign of possible microburst activity.
air sinking air from a storm cloud’s downdraft spreads out across the
surface with the leading edge called a gust front. This outflow
undercuts warm air being drawn into the storm’s updraft. As the cool air
lifts the warm moist air water condenses creating cloud, which often
rolls with the different winds above and below (wind shear).
9. Shelf Clouds
shelf cloud is a low, horizontal wedge-shaped arcus cloud, associated
with a thunderstorm gust front (or occasionally with a cold front, even
in the absence of thunderstorms).
Unlike a roll cloud, a shelf cloud is attached to the base of the parent cloud above it (usually a thunderstorm).
cloud motion often can be seen in the leading (outer) part of the shelf
cloud, while the underside often appears turbulent, boiling, and
10. Stratocumulus Clouds
to the Sapporo Meteorological Observatory, these low-altitude
stratocumulus clouds were rolled into long, distinctive ribbons after
becoming trapped in air currents.
it is not uncommon for wind to form such patterns in stratocumulus
clouds, photos that clearly show the clouds rolled into strips are rare,
says the observatory.