Warning signal, with skill, sounded (5)
I believe the answer is:
flare
'warning signal' is the definition.
(I've seen this in another clue)
'skill sounded' is the wordplay.
'skill' becomes 'flair' (I've seen this before).
'sounded' shows a homophone (sound like).
'flair' sounds like 'FLARE'.
'with' is the link.
(Other definitions for flare that I've seen before include "Feral kind of sudden activity" , "Distress signal; burst out angrily" , "Burst into sudden activity or anger" , "Sudden burst of flame" , "Blaze with sudden irregular flame" .)