Right arm is not broken in heavy fall (9)
I believe the answer is:
rainstorm
'heavy fall' is the definition.
(I've seen this before)
'right arm is not broken' is the wordplay.
'right' becomes 'R' (common abbreviation).
'broken' indicates an anagram.
'arm'+'is'+'not'='armisnot'
'armisnot' anagrammed gives 'ainstorm'.
'r'+'ainstorm'='RAINSTORM'
'in' is the link.
(Other definitions for rainstorm that I've seen before include "squall" , "Heavy downpour" , "Wild weather" , "power shower?" , "ferocious weather" .)