Fine rain put an end to foremost of matches -- it's sad (6,4)
I believe the answer is:
scotch mist
'fine rain' is the definition.
(I've seen this before)
'put an end to foremost of matches it's sad' is the wordplay.
'put an end' becomes 'scotch' (I've seen this before).
'to foremost of' says to take the initial letters.
'sad' indicates an anagram.
The initial letter of 'matches' is 'm'.
'its' with letters rearranged gives 'ist'.
'scotch'+'m'+'ist'='SCOTCH MIST'
(Other definitions for scotch mist that I've seen before include "Thick Highland drizzle" , "Highland weather" , "fine shower" , "Fine rain - something unsubstantial" , "Something insubstantial" .)