It looks like cold arctic air is coming down across eastern Canada. We may have a major snowstorm next weekend all depends on the track of the storm of course. The Nao which is the North Atlantic Oscillation is expected to remain negative for awhile then go neutral then go very negative after the 16th of Dec. The PNA which stands for the Pacific/North American pattern is expected to remain negative. Another reason why the cold air will remain locked in place is that a big block is developing. This pattern looks to last at least 3 weeks. The Euro Weeklies suggest that this pattern will continue into the New Year. We will see.