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meteorological advices
2 – me t eorology
SIGMET
SIGMET information concerns the occurrence or expected occurrence, in an
area overwhichmeteorological watch is beingmaintained, of oneormoreof
the following:
- thunderstorms
- tropical cyclones
- severe line squalls
- hail
- severe turbulence
- severe icing
- severemountainwaves
- heavy sandstorms or duststorms
- volcanic ash cloud
Pilots in command of aircraft encountering any of the abovephenomena,
not notified by SIGMET advices,must report details of the phenomena in an
AIREPSPECIAL.
SIGMET information is issued byMET forecasters and addressedbyATS as
aHazardAlert to aircraft operating on routes or in areas likely to be affected.
This informationwill normally relate the phenomena reported to designated
reportingpoints, andwhere possible, will indicate the area inwhich the
phenomena exist.