The 06z GFS run, if it has finally found the acorn (blind squirrel etc) confirms the idea that this cold spell won't relent very easily. There isn't really an above normal day on the run, let alone a breakdown. I think weather forecasters around the region are going to have the breakdowns before the weather does at this rate.
Anyway, I hold out some hope for snow for just about all regions between now and Christmas, based on the concept I explained once before in another thread.
Suppose you have four or five days in a row with "slight chances" of something happening, in this case snow. Is it therefore true to say there is a slight chance of that happening any time in the four or five days?
No, and here's why, using the laws of probability.
I'll take as my example a theoretical 20% chance of snow from streamers any day now to Friday, that's six days, each with a 20% chance of snow. In fact the chances might be better than that, but I'll show that even with this rather grim negative-sounding assessment, you would probably get snow.
The probability chances of getting no snow in just three days, using that 20% figure, is this:
1.0 - (.8 x .8 x .8) =
1.0 - (.512) = .488
In other words, your chances of missing snow every day for three days in that sort of framework, would be 51.2% giving you a 48.8% chance to see snow. For six days, that reduces to a mere 26% chance of avoiding snow and a 74% chance of seeing snow.
In other words, a long-duration marginal setup usually delivers. Which day it delivers, makes for very difficult forecasting. But would look for the day with the strongest wind gradient from the best direction as your odds-makers' favourite. Personally, I think it will snow eventually just about everywhere in this set-up. But it will be dry most of the time too. The combination should suit everyone, the snow fancier, the merchant, the person who needs to travel -- let's hope everyone feels they got what they wanted for Christmas.