Cyclist has her day in the lead, weather having improved (5)
I believe the answer is:
drier
'weather having improved' is the definition.
(as in dry weather)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for drier that I've seen before include "Machine giving spin" , "Less moist" , "Less wet" , "getting less rainfall" , "less interesting" .)