Cloud Classification

Question 1

Cl

What do Castellus clouds look like?

Answer 1

Row of turrets
This is a group of cumulus clouds

Question 2

What do Cirrus Avatics look like?

Answer 2

Indicator of high humidty

Question 3

Describe Cirrus Clouds

Answer 3

High level, streaky
CI

Question 4

Describe Cirrocumulus

Answer 4

High level, puffy clouds
CC

Question 5

Describe Cirrostratus

Answer 5

High level clouds that hide the sun

Question 6

Describe Altocumulus

Answer 6

Mid level cumulus clouds
AC

Question 7

Describe Altostratus

Answer 7

Midlevel clouds that hide the sun
AS

Question 8

Describe Nimbostratus

Answer 8

Rainbearing clouds - low level - hiding the sun

Question 9

Describe Stratocumulus

Answer 9

Cumulus clouds that hide the sun

Question 10

Describe Stratus

Answer 10

Low level clouds - hiding the sun

Question 11

Describe Cumulus clouds

Answer 11

Puffy, with vertical shape.
Can be fair weather

Question 12

Describe cumulonimubus

Answer 12

Rain bearing cumulous clouds

Question 13

Describe Towering Cumulus

Answer 13

Large amounts of vertical extent.
Indicates strong updrafts and downdrafts

Question 14

What are lenticular clouds?

Answer 14

Lens shaped.
Common in NZ - due to terrian
Indicate high winds ( sometimes > 60kts )
The mountain winds can spread a long way.

Question 15

What is dangerous about Cumulonimbus?

Answer 15

Often strong updrafts and down drafts
Can result in heavy rain.
Top can be shaped like an anvil

Question 16

Are cumulus clouds dangerous?

Answer 16

Can be fair weather clouds.
If they are shallow they do not produce rain.
anything with a vertial extent of > 10,000 ft can be dangerous.

Question 17

Describe the overall cloud classificaitons

Answer 17

Question 18

What is the measure of cloudbase?
4 methods to measure?

Answer 18

Height above airport elevation.
Observer - looking at features
Hydrogen Balloon - time to ascend into cloud
Search Light - trigonmatety ( angle )
Ceilometer - most common, uses light pulses.

Question 19

What is provided in the METAR if the cloud base can not be determined?

Answer 19

Sometimes the vertical visiblity.

Question 20

What is the definition of the ‘ceiling’

Answer 20

When the clouds cover at least 1/2 of the sky. ( 5+ OKTAs )
Meaning Broken or Overcast ( NOT Scattered or Few )

Question 21

What are the definitions of cloud cover ( names, abrevations and OKTAs )

Answer 21

Clear - CAVOK - 0 OKTA
Few - FEW - 1 - 2 OKTA
Scattered - SCT - 3 - 4 OKTA
Broken - BKN - 5 - 7 OKTA
Overcast - OVC - 8 OKTA