Seasonal wind for a day in the near future (7)
I believe the answer is:
monsoon
'seasonal wind' is the definition.
(I've seen this before)
'day in the near future' is the wordplay.
'day' becomes 'mon' (abbreviation for Monday).
'in the near future' becomes 'soon' (I've seen this before).
'mon'+'soon'='MONSOON'
'for a' acts as a link.
(Other definitions for monsoon that I've seen before include "Season of heavy rain" , "Wild weather" , "Rain-bringing wind" , "Rain-bringing weather feature" , "Seasonal wind and rain in S Asia" .)