Office worker set off a storm (7)
I believe the answer is:
tempest
'a storm' is the definition.
(I know that storm can be written as tempest)
'office worker set off' is the wordplay.
'office worker' becomes 'temp' (short-term or temporary worker).
'off' indicates anagramming the letters.
'set' is an anagram of 'est'.
'temp'+'est'='TEMPEST'
(Other definitions for tempest that I've seen before include "Violent storm (created by Shakespeare?)" , "violent agitation" , "Violent windy storm" , "Shakespeare play with storm scene" , "Shakespeare's 5" .)