On face value, whilst I am inclined to agree with that assessment, you never know what can pop up. Ian F left some interesting comments earlier about the current set up. As TEITS has mentioned above, it's where the blocking occurs that's the crucial factor. The latest operational GFS is not in a favourable position for colder weather over the whole UK, not just the South. Still plenty of winter left for something colder, but at the moment, like you, I can't see anything too obvious in the current outputs for sustained cold.