What does a Convective SIGMET indicate?

A Convective SIGMET specifically indicates the occurrence of severe thunderstorms or other significant convective weather phenomena. It is issued when certain criteria related to thunderstorms are met, such as the presence of thunderstorms producing wind gusts of 50 knots or greater, tornadoes, hail of 3/4 inch in diameter or larger, or when thunderstorms cause a significant impact on aviation and flight safety.

The primary purpose of a Convective SIGMET is to alert pilots and air traffic controllers of potentially hazardous weather conditions that can affect flight operations. By focusing on severe thunderstorms, this type of SIGMET enables pilots to take appropriate precautions when flying in areas where such weather is detected.

By contrast, options indicating widespread visibility or concerns about icing or surface winds do not directly pertain to severe thunderstorms, which is why those choices are not relevant in this context. Understanding the specific criteria and implications of a Convective SIGMET is essential for safe aviation operations in the presence of convective weather.