When is a Convective SIGMET issued?

A Convective SIGMET is issued when there is a significant risk of severe convective weather, such as thunderstorms, that could affect aviation safety. These SIGMETs are issued on an as-needed basis when conditions meet certain criteria, rather than at fixed intervals.

The primary purpose of a Convective SIGMET is to alert pilots and air traffic controllers to the possibility of severe hazards like tornadoes, severe thunderstorms with a likelihood of producing hail, or turbulence caused by convective activity. As conditions can change rapidly in the atmosphere, timely updates are essential.

While the specific issuing frequency can vary based on ongoing weather conditions, the emphasis is on the need for timely and relevant warnings, which might require updates more frequently than every 2 hours. Therefore, the correct understanding of how often Convective SIGMETs are issued revolves around ensuring that critical information is available to pilots as soon as significant convective activity is detected, rather than adhering to a fixed schedule.