ITA-Block 4

Question 1

What are the three stages of a thunderstorm?

Answer 1

Cumulus, mature, and dissipating

Question 2

What are the two main types of thunderstorms?

Answer 2

Air mass thunderstorms and frontal thunderstorms

Question 3

What causes air mass thunderstorms?

Answer 3

Convection or orographic lift

Question 4

What causes frontal thunderstorms?

Answer 4

Mostly cold fronts, but sometimes warm fronts

Question 5

Gust front

Answer 5

The result of strong downdrafts in the mature stage of a thunderstorm which spreads out horizontally when it reaches the ground

Question 6

Downburst

Answer 6

A severe downward rush of air Can be classified as microbursts or macrobursts

Question 7

Macroburst

Answer 7

A argue downwind burst Diameter of two miles or more Lasting 5-20 mins

Question 8

Microburst

Answer 8

A downburst less than two miles in diameter Lasts ten to twenty minutes Classified as wet or dry Speed up to 6000 feet per minute Horizontal ground level winds of up to 80knots

Question 9

Virga

Answer 9

When precipitation falls but doesn’t reach the ground Often a precursor of microbursts

Question 10

Squall lines

Answer 10

Non frontal, narrow bands of highly active thunderstorms Range from one to several hundred miles in length Can be broken or a continuous line

Question 11

Cumulonimbus mamma cloud

Answer 11

A round under hanging of the cloud that may be an indictation of a tornado.

Question 12

Two types of turbulence

Answer 12

Thermal and friction

Question 13

What are the types of friction turbulence?

Answer 13

Mechanical turbulence, shear turbulence, frontal turbulence

Question 14

What are the types of thermal turbulence?

Answer 14

Daytime convection and cold air advection

Question 15

Daytime convection turbulence

Answer 15

Turbulence caused by the uneven heating of the earths surface

Question 16

Cold air advection turbulence

Answer 16

When cold air moves over warmer water or land, heating from below and causing turbulence

Question 17

Clear air turbulence

Answer 17

CAT Jet stream turbulence

Question 18

Conditions for clear air turbulence

Answer 18

No clouds Strong jet stream Rapid change in wind speed Rapid change in wind direction

Question 19

Turbulence

Answer 19

An irregular motion of the air resulting from the formation of eddies or vertical currents in the air

Question 20

Requirements for thunderstorm formation

Answer 20

-unstable air -lifting action -air with a high moisture content

Question 21

Information in a METAR

Answer 21

Message type Station identifier Observation time Wind Visibility RVR Present weather Sky cover Temperature Dew point Altimeter Recent weather Wind shear Remarks

Question 22

When are METARS usually taken?

Answer 22

On the hour

Question 23

SPECI

Answer 23

A report taken at any time to report significant weather not previously reported

Question 24

TAF

Answer 24

Aerodrome forecast that is broken down into time segments Do not include temperature or pressure

Question 25

PIREP

Answer 25

A report of weather conditions encountered by an aircraft in flight Must indicate whether it is urgent (UUA) or normal (UA), location, flight level, and aircraft

Question 26

SIGMET

Answer 26

A SIGMET is only issued for the most serious hazards Issued when the phenomena is forecast to occur in the next four hours The exception is for volcanic ash which can be forecast up to 12 hours in advance Valid for up to four hours

Question 27

What phenomena can a SIGMET be used to report?

Answer 27

Areas of active thunderstorms Lines of thunderstorms Hurricanes/tropical storms Heavy hail Severe turbulence Severe icing Marked mountain waves Widespread sand or dust storms Volcanic ash cloud LLWS severe squall line Tornado or waterspout

Question 28

AIRMET

Answer 28

A short term weather advisory intended for pilots in flight not previously stated or to amend GFA Issued by weather centres across Canada Valid until updated, cancelled or the next GFA.

Question 29

GFA

Answer 29

Graphic Area Forecast

Question 30

FD

Answer 30

Forecast Digital Upper winds and temperatures chart Code : ddff+/-tt If wind speed 100KTS and above, a value of 50 is added to the direction Issued by cdn met centre in Montreal or in U.S. National weather service in Suitland, Maryland

Question 31

Answer 31

A land aerodrome without hard surfaced runways