Weather Services

Question 1

Aviation Area Forecast (FA)

Answer 1

A forecast of general weather conditions over the area the size of several states

• issued 3 times a day
• 4 sections; communications and product header, precautionary statement section, synopsis WX, and VFR clouds/WX

Question 2

Inflight weather advisories (WA, WS, WST)

Answer 2

Severe weather watch bulletins are areas of possible thunderstorm or tornado activity
- unscheduled and issued as required

Question 3

AIRMETs (WA)

Answer 3

Information on WX hazardous to single engine/light aircraft and VFR pilots 
Covers
- moderate icing or turbulence 
- sustained winds >30 knots at surface 
- widespread IFR conditions 
- extensive mountain obscurement 
Broadcast upon receipt and in 30min intervals 
(H+15, H+45)

Question 4

SIGMETs (WS)

Answer 4

Advise of weather hazardous to all aircraft
Covers
- severe icing
- severe or extreme turbulence
- sandstorm, dust storms or volcano ash. lowering visibility to

Question 5

CONVECTIVE SIGMETs (WST)

Answer 5

Covers
- tornadoes 
- lines of thunderstorms
- embedded thunderstorms
- severe or extreme turbulence 
- severe icing 
- Low-level wind shear
Broadcast upon receipt and in 15 min intervals 
(H+15, H+30, H+45)

Question 6

Terminal Aerodrome Forecast (TAF)

Answer 6

Expected meteorological conditions at an airport during a specific time (usually 24h)
- covers 5 statute miles from the center of an airports runway complex