Country rain storm (4)
I believe the answer is:
iran
'country' is the definition.
(Iran is a country)
'rain storm' is the wordplay.
'storm' indicates anagramming the letters.
'rain' is an anagram of 'IRAN'.
(Other definitions for iran that I've seen before include "Middle East country" , "It used to be Persia" , "Middle Eastern country" , "Former Persia" , "Nation" .)