Time wind swirls over river, height of season
I believe the answer is:
midwinter
'height of season' is the definition.
The definition suggests a singular noun which matches the answer.
'time wind swirls over river' is the wordplay.
'swirls' indicates an anagram.
'over' is a charade indicator (letters next to each other).
'river' becomes 'r'.
'time'+'wind'='timewind'
'timewind' with letters rearranged gives 'midwinte'.
'midwinte'+'r'='MIDWINTER'
Can you help me to learn more?
(Other definitions for midwinter that I've seen before include "Bleakest time of year?" , "Date of holy birth" , "height of season?" .)