Tempests (6)
I believe the answer is:
storms
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tempests</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for storms that I've seen before include "They occur at force 10 or 11 on the Beaufort scale" , "Weather periods when winds are force 11" , "They occur when winds reach force 10" , "Tempests" , "Outbreaks of violent weather" .)