Cloud classification

Question 1

What height does low level cloud extend to?

Answer 1

6500ft AMSL

Question 2

What height does the medium or Alto cloud level extend from and to?

Answer 2

6500-23000ft AMSL

Question 3

What height does the Cirro cloud level extend from and to?

Answer 3

16500ft - +23000ft AMSL

Question 4

Name the three cloud types and their basic shapes?

Answer 4

Stratiform - generally flat, wide with little vertical extent

Cumuliform - tall with little horizontal extent

Cirriform - fibrous, wispy, high level

Question 5

Fractus cloud is?

Answer 5

Fractured or broken clouds, common beneath heavy rain clouds

Question 6

Castllanus cloud is?

Answer 6

Castle like, turreted and sits atop other clouds.

Eg alto cumulus castellanus

Question 7

Mammatus cloud is?

Answer 7

Like boobs or udders. Hang below other cloud forms. Soft, curved edges.

Question 8

Lenticularis cloud is?

Answer 8

Lens or lentil shaped. Can be seen formed by mountain wave.

Question 9

Capillatus

Answer 9

Large anvil shaped cloud

Question 10

Stratus is?

Answer 10

Grey, layered, can result in fog from convection / isolation

Question 11

Altocumulus is?

Answer 11

White or grey, sheets and layers than can produce rain.

Question 12

Altostratus is?

Answer 12

Totally or partly covers the sky but it can be thin enough to reveal sun. Can produce light rain

Question 13

Nimbrostratus is?

Answer 13

Dark, blocks sun. Almost always produces RA or SN

Question 14

Virga is?

Answer 14

Rods. Rain that doesn’t reach the ground. Very hazardous to flight.

Question 15

Stratocumulus is?

Answer 15

White, grey layered with dark parts. Round masses which can merge.

Question 16

Cumulus is?

Answer 16

Sharp outline, fluffy, child drawing of a cloud. Tall and small horizontal extension.

Question 17

Cumulonimbus is?

Answer 17

Heavy and dense. Very tall. Under the base which is often dark, there can be fractured cloud. Produce +RA, SN and GS. Avoid at almost all costs.

Question 18

Lenticularis is?

Answer 18

Sharply defined lens shapes. Avoid due to association with mountain wave.

Question 19

Castellanus is?

Answer 19

Indicates mid level instability and there indicates thunderstorm development. Flat bases, turrets at various points. Can apply to cirrus, altocumulus and stratocumulus.

Question 20

Fractus is?

Answer 20

Broken or ragged appearance.

Question 21

Capillatus is?

Answer 21

Anvil shaped. Protrudes from cirriform cloud.