Which weather system had the most consequential effect in naval history?
Short answerProbably the storm that destroyed the Mongol invasion fleet headed for Japan.
NotesWeather has altered many campaigns, but both speakers select the storm that struck the Mongol invasion fleet bound for Japan. Its significance extends beyond a single tactical engagement because the fleet's destruction helped prevent an invasion. Consequence here is measured by the political and strategic history that did not follow, not simply by ships lost. This is the strongest example offered rather than a complete ranking of every cyclone, storm, or anticyclone in naval history.