Celebrate what will be announced (4)
I believe the answer is:
fete
'celebrate' is the definition.
(synonyms)
'what will be announced' is the wordplay.
'what will be' becomes 'fate' (I've seen this in another clue).
'announced' indicates a 'sounds like' (homophone) clue.
'fate' is a homophone of 'FETE'.
(Other definitions for fete that I've seen before include "Fundraising event" , "Outdoor charity function" , "Celebrate; village fair" , "Big outdoor party" , "Village festivity" .)