How often is a SIGMET issued?

A SIGMET, or Significant Meteorological Information, is issued as needed rather than at fixed intervals. This means that the frequency of issuance depends on current weather conditions that could potentially affect the safety of aircraft operations.

While an answer of every 4 hours may seem structured, the reality of SIGMET issuance relies on the presence of significant weather phenomena, such as severe turbulence, thunderstorms, or volcanic ash, that could impact aviation. Therefore, if such events are occurring or are anticipated, a SIGMET will be issued promptly, regardless of any pre-determined time frame.

This flexible nature of SIGMET issuance underscores its critical role in ensuring the safety and efficiency of flight operations by providing real-time updates on hazardous weather conditions.