Wind in the morning upset girl (5)
I believe the answer is:
maria
'girl' is the definition.
'wind in the morning upset' is the wordplay.
'wind' becomes 'air' (air is a kind of wind).
'in the morning' becomes 'am'.
'upset' shows that the letters should be reversed in order.
'air'+'am'='airam'
'airam' backwards is 'MARIA'.
(Other definitions for maria that I've seen before include "Black --, -- Theresa" , "Lady" , "Dark planes on the moon; girl's name" , "West Side Story girl" , "Heroine of West Side Story" .)