Cloud Classification Flashcards
Cl
What do Castellus clouds look like?
Row of turrets
This is a group of cumulus clouds
What do Cirrus Avatics look like?
Indicator of high humidty
Describe Cirrus Clouds
High level, streaky
CI
Describe Cirrocumulus
High level, puffy clouds
CC
Describe Cirrostratus
High level clouds that hide the sun
Describe Altocumulus
Mid level cumulus clouds
AC
Describe Altostratus
Midlevel clouds that hide the sun
AS
Describe Nimbostratus
Rainbearing clouds - low level - hiding the sun
Describe Stratocumulus
Cumulus clouds that hide the sun
Describe Stratus
Low level clouds - hiding the sun
Describe Cumulus clouds
Puffy, with vertical shape.
Can be fair weather
Describe cumulonimubus
Rain bearing cumulous clouds
Describe Towering Cumulus
Large amounts of vertical extent.
Indicates strong updrafts and downdrafts
What are lenticular clouds?
Lens shaped.
Common in NZ - due to terrian
Indicate high winds ( sometimes > 60kts )
The mountain winds can spread a long way.
What is dangerous about Cumulonimbus?
Often strong updrafts and down drafts
Can result in heavy rain.
Top can be shaped like an anvil
Are cumulus clouds dangerous?
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.
Describe the overall cloud classificaitons
What is the measure of cloudbase?
4 methods to measure?
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.
What is provided in the METAR if the cloud base can not be determined?
Sometimes the vertical visiblity.
What is the definition of the ‘ceiling’
When the clouds cover at least 1/2 of the sky. ( 5+ OKTAs )
Meaning Broken or Overcast ( NOT Scattered or Few )
What are the definitions of cloud cover ( names, abrevations and OKTAs )
Clear - CAVOK - 0 OKTA
Few - FEW - 1 - 2 OKTA
Scattered - SCT - 3 - 4 OKTA
Broken - BKN - 5 - 7 OKTA
Overcast - OVC - 8 OKTA
