Overview Flashcards
A over view of met observe qualification
When is the wind speed coded as VRB ?
When the wind speed is 3knots or less and when the wind direction is is more than 60 degrees or more but less than 180
If the wind direction has a variation of 180 degrees or more and has speed faster than 3 knots what will it be coded as?
VRB
How would you code winds greater than 99kts?
P99
What is minimum visibility
When the visibility is less than 1500m or less50% if the prevailing vis in one direction.
When the visibility is less than 800m is should be rounded to?
The nearest 50m
When the visibility is 800m or more but less than 5000m rounded down to?
The nearest 100m
When the visibility is 5000m or more the visibility shall be rounded to
The nearest 1000m.
When the visibility is less than 50m how shall it be encoded?
0000
How shall a visibility of 50m be encoded?
0050
How shall a visibility of 10km be encoded?
9999
When is the RVR reported?
When the visibility is less than 1500m
When the RVR is less than 50m how shall is be reported?
M0050
How many figures shall be are used to report the visibility?
4 figures even for RVRs.
When th RVR value is greater than 2000m how shall it be reported?
P2000
When the RVR is less than 400m is shall be rounded to the nearest?
25m
When the RVR is between 400-800m it shall be rounded down to?
50m
When the RVR is greater than 800m it shall be rounded to the nearest?
100m
How should different types of precipitation occuring at the same time be reported?
As one single group
The dominant type of precipitation should be reported first and preceded by only one intensity qualifier which refers to the intensity not total precipitation.
True
What does this symbol mean -
Light
What does this symbol mean +
Heavy
What does VC mean?
In the vicinity
How would you code Fog in the vicinity?
VCFG
How would you code sleet?
RASN or SNRA whichever precipitation is more dominant
What are the conditions for fog to be reported?
Visibility less than 1000m and relative humidity at or near 100%
Code for hail
GR
What is the code for small hail?
GS
What is the difference between hail and small hail?
Hail has a diameter of 5mm whilst small hail’s is less.
What are the conditions for haze?
Relative humidity is less than 95% and the difference between temperature is usually greater than 1 degree
Conditions for mist?
Vis between 1000-5000m relative humidity is 95% or higher and difference between temp and dewpoint is usually 1 degree or less.
Code for partial
PR
Code for patches
BC
Code for snow grains
SG
What does NSC mean?
No cloud below 5000ft
