special marine warning
Definition
A meteorological notice issued by the National Weather Service (NWS) indicating the presence of a localized, short-duration event, such as a thunderstorm or squall line, that poses an immediate threat to life and property over marine waters.
A wake-up call for boaters that essentially means 'if you stay out there, you are choosing a very damp and potentially perilous adventure'.
Examples
The captain ignored the special marine warning, proving that some people prioritize their pride over the fundamental laws of buoyancy.
Receiving a special marine warning on your phone is nature's way of suggesting that your yacht lifestyle might need a brief, mandatory hiatus.
I checked the radar one last time, saw the special marine warning, and decided that my couch was exactly the kind of nautical vessel I needed for the evening.