Real trouble checking temperature in the future (5)
I believe the answer is:
later
'in the future' is the definition.
(I've seen this before)
'real trouble checking temperature' is the wordplay.
'trouble' indicates an anagram.
'checking' indicates putting letters inside (inserted letters are controlled or checked).
'temperature' becomes 't' (abbreviation).
'real' is an anagram of 'laer'.
'laer' enclosing 't' is 'LATER'.
(Other definitions for later that I've seen before include "succeeding" , "Following" , "after the rest?" , "goodbye" , "at a subsequent point" .)