Bringing a timely warning (8)
I believe the answer is:
salutary
'bringing a timely warning' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for salutary that I've seen before include "Promoting good health" , "Beneficial in providing a lesson" , "Containing or bringing a timely (health) warning" , "Good for one" , "Beneficial in providing educating experience" .)