A current convective SIGMET, a weather advisory, signals the presence of hazardous thunderstorm activity. This indicates that thunderstorms with characteristics such as severe turbulence, hail greater than or equal to 3/4 inch in diameter, or embedded thunderstorms are occurring or expected to occur within the designated area. It may also warn of heavy precipitation affecting at least 40% of an area 3,000 square miles or greater. For example, a convective SIGMET issued for a specific region might alert pilots to the risk of encountering strong downdrafts and potential icing conditions associated with intense storm cells.
The issuance of these advisories is crucial for aviation safety. Providing timely notice of these hazards allows pilots to make informed decisions about flight paths, potentially avoiding dangerous weather phenomena. The National Weather Service has a long history of developing and refining these forecasting methods, with the initial iterations of severe weather advisories evolving into the modern convective SIGMET system to better serve the needs of the aviation community.
