The forecast here in Suffolk is for around 12C on Monday (and only dropping to 11C overnight into Tuesday), with quite a bit of light rain around in the run-up to Christmas. I won't miss the cold weather!
Some predictions for global warming say that it could mean that the Gulf Stream will move away from the UK, so that we'll then get weather that's much the same as those parts of Canada that are on the same latitude as we are. If so, this is what we've got to look forward to:
https://www.bbc.co.uk/weather/5913490