Break’s very warm — a record at the moment (8)
I believe the answer is:
snapshot
'a record at the moment' is the definition.
(record of a particular moment)
'break's very warm' is the wordplay.
'break's' becomes 'snap's'.
'very warm' becomes 'hot' (I've seen this before).
'snaps'+'hot'='SNAPSHOT'
(Other definitions for snapshot that I've seen before include "Quick photograph" , "Casual photograph" , "Bit of camerawork" , "Informal photograph" , "Instant record of an event" .)