Meteo Flashcards
Who creates upper air forecasts
The World Area Forecast Centers
How many World Forecast Area centers are there
- One in Washington and one in London
How do the VAAC (Vulcanic Ash Advisory Centers) send their information?
In Warnings in the form of NOTAMs and SIGMETs
Who provides meteorological service in a flight information region?
The Meteorological watch office
What kind of messages do MWO’s send out?
AIRMETs and SIGMETs
How often does an ARO send out it’s weather information?
At least once every hour
What kind of message does an ARO send out?
METAR
What is in a METAR?
Wind direction / speed
visibility
weather (if any)
clouds
temperature / dewpoint
QNH
With what instrument is wind measured?
Anemometer
With what instruments is visibility measured
Transmissometer and scattermeter
When is NDV “No directional Variation) mentioned in a METAR?
If it is an auto ops in only one dircetion
With what equipment do we measure the weather?
Present weather sensor
How is the amount of clouds measured?
In octas
How would we call 75% cloud coverage?
Broken
How would we call 45% cloud coverage?
Scattered
Can we replace the weather and clouds in the following METAR as CAVOK?
EKCH 061420Z 23012kts 9999 OVC060 16/12 Q1007
Yes
Can we replace the weather and clouds in the following METAR as CAVOK?
EKCH 061420Z 23012kts 9999 OVC055CB 16/12 Q1007
No
Can we replace the weather and clouds in the following METAR as CAVOK?
EKCH 061420Z 23012kts 8000 NCD 16/12 Q1007
No
Can we replace the weather and clouds in the following METAR as CAVOK?
EKCH 061420Z 23012kts 9999 NCD 16/12 Q1007
Yes
What is the MSA
Minimum Sector altitude. Highest obstacle withing 25nM of aerodrome rounded up to the next 100ft + 1000 ft
The highest obstacle in a 25NM radius of an Aerodrome is 914 feet. What would be the MSA?
2000 ft
What is the difference between cloud base and cloud ceiling?
The cloud base is the lowest of any clouds. The cloud ceiling is from what height at least 50% of the sky is covered in clouds.
Can an Automated Weather Observation System (AWOS) make a full METAR automatically?
Yes
On what principle is a wet-and-dry bulb themometer based?
Latent heat of water
How are Upper Air observations taken?
With weather balloons, released twice a day at 0000 and 1200 UTC
How big is a box in Numerical Weather prediction?
10x10x10 km
How atmospheric properties predicted in Numerical weather prediction?
By previously measured interactions betweens cells
A meteorological Watch office shall be associated with each?
ATS Unit
TWR / APP are associated with what kind of meteorological institution?
Aerodrome meteorological office
ACC is associated with what kind of meteorological institution?
Meteorological watch office
What is AFTN?
Aeronautical Fixed Telecommunication Network. Worldwide telex for METAR, TAF etc.
Do aircraft have acces to the Aeronatical Fixed Telecommunication Network?
No. (It is fixed. Airplanes are not fixed)
Name all the layers of our atmosphere from low to high
Troposphere
Tropopause
Stratosphere
Stratopause
Mesosphere
Mesopause
Thermosphere
Thermopause
Exosphere
How is the tropopause defined?
Temperature defined. -56.5 degrees celsius
What is the height of the troposphere?
There is no fixed height since it’s temperature defined and temperature varies from place to place and day to day
What are the three biggest factors that impact air density?
Humidity, altitude and temperature
How many of all water in the atmosphere is in the troposphere?
99%
What is the height of the troposhpere in ISA?
36090 feet, or 11km
How is an air mass defined?
As an area with similar temperature in humidity over the horizontal plane
What is the pressure laps rate at 20 000 ft?
1hpa per 50 ft