What is a sigmet?

A SIGMET (Significant Meteorological Information) is a weather advisory issued by meteorological offices to warn pilots of potentially hazardous weather conditions that could impact aircraft operations. SIGMETs are issued for weather phenomena such as severe turbulence, severe icing, thunderstorms, dust storms, and volcanic ash clouds.

SIGMETs are typically issued for a specific area and have a valid period of a few hours. They are transmitted to aircraft in flight through various communication systems, such as air traffic control, flight service stations, and automatic data link systems.

Pilots are required to take SIGMETs into account when planning their flights and may need to alter their routes or delay their departures or landings to avoid hazardous weather conditions. SIGMETs are an important tool for ensuring the safety of air travel in challenging weather conditions.