( Roger J Smith just posted this in the main thread !! UPGRADE ALERT checking out the latest updated charts aswell )
I'm going to continue to beat the drum for potential blizzard conditions in south coast counties on Sunday night into Monday, the low is taking what seems to be the ideal track to interact with bitterly cold winds forced to a cyclonic path across the Channel, and the similarity to the Jan 1881 historic blizzard set-up is noteworthy.
I have the feeling that some are underestimating the potential of this dynamic situation. You have extremely cold uppers racing south and meeting this Atlantic moisture head-on. Temperatures are still 8-10 C all across the Channel region and can't be suppressed all that much before the storm sets in. My prediction is that a severe snowstorm will develop rapidly across most of southern England on Sunday night and some amounts will be large with this, not just on the bleakest part of Dartmoor either. Yes, a sharp northern cutoff somewhere around or south of the M-4 with other unrelated areas of heavy snow from the North Sea inland.
Not much time to wait now. This is coming, you won't get these very cold uppers in play without a big snowstorm. Channel Islands will be included eventually, may start as rain or sleet with thunderstorms then change over to snow. IOW may actually jackpot in this set-up although inland Dorset to east Devon looks favoured also. And I think at present the chances are greater than 50-50 that this would spread into at least the southern half of greater London and most of Kent-Surrey-Sussex, however, there will be a sharp northerly cut-off and north London may see much less.