Very latest express frequently runs in hot weather (5-2-3-3)
I believe the answer is:
state-of-the-art
'very latest' is the definition.
'state of the art' can be an answer for 'latest' (I've seen this before). I am unsure of the 'very' bit.
'express frequently runs in hot weather' is the wordplay.
'express' becomes 'state' (synonyms).
'frequently' becomes 'oft' (oft can mean frequently, eg oft-quoted).
'runs' becomes 'r' (cricket abbreviation).
'in' indicates putting letters inside.
'hot weather' becomes 'heat'.
'r' inserted within 'heat' is 'heart'.
'state'+'oft'+'heart'='STATE-OF-THE-ART'
Can you help me to learn more?
(Other definitions for state-of-the-art that I've seen before include "Produced by the latest technology" , "Technologically up to date" , "Up-to-date technically" , "Incorporating the latest technologies" , "Bang up-to-date" .)