Brian, that isn't the correct interpretion of the Op and the ensemble. As you know the Op Takes the opening position and yields an expected evolution. The ensemble run tests the sensitivity of the evolution to tiny changes in the starting data. To say the Op is 'anomalous' is therefore misleading: surely the message is that the evolution shown by the Op is unusually risky by Day 10? In any event the 2m temperature chart below suggests the Op remained within the cold cluster.
Anway, here is the ECM 12z ensemble for London

ECM and GFS in remarkable and rare agreement right out to day 9. A lot of the uncertainty shown for early next week in the 00z has vanished again.
Quite a strong signal for a possibly brief Atlantic breakthrough on 14th but little to suggest a sustained milder spell and a cluster giving colder conditions again is evident - although not a strong signal.
Originally Posted by: Gandalf The White