Cheerful when there's a wind! (6)
I believe the answer is:
breezy
'cheerful' is the definition.
(thesaurus)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for breezy that I've seen before include "Blowy" , "Slightly windy" , "Fresh and animated" , "Lively - exhilarating" , "Fresh - jaunty" .)