Those probability maps always seem rather pointless to me as they rarely ever show a strong signal for any particular tercile. Seeing as all they can do is demonstrate the likliness of certain setups based on their data... what use can they really be?
The ensemble mean maps are far more helpful and, from what I've seen, have also proved a reasonable guide to the broad-scale patterns over the past season or two. The September update is very similar to the August update - which raises confidence in the idea of high-latitude blocking being prominent to the north (potential areas span the regions to the NW, N and NE) of the UK for the greater part of the winter. Of course that still allows for considerable variation from that blocking setup for the lesser part of the winter.
The fact that the above and the multi-run CFS mean are quite similar has me anticipating at least one month of widespread high-lat. blocking this coming winter, with a good chance of the blocks aligning nicely for the UK - particularly in light of Gavin's musings regarding that NE Pacfic +ve SST anomaly.
Originally Posted by: Stormchaser