Sunny with strong wind (4)
I believe the answer is:
fair
'sunny' is the definition.
('fair' can be similar in meaning to 'sunny')
'with strong wind' is the wordplay.
'with' is a charade indicator (letters next to each other).
'strong' becomes 'f' (**).
'wind' becomes 'air' (air is a kind of wind).
'f' put next to 'air' is 'FAIR'.
(Other definitions for fair that I've seen before include "Just right" , "Equitable or blond" , "(Of weather) fine and dry" , "Beautiful like maiden of old" , "Satisfactory" .)