UPDATE: Friday 5 Feb 2010 / 9:30p.m.
The forecast regarding the arctic air mass remains basically the same. Tuesday will be quite windy and much colder with highs struggling into the low to mid 30s. There will be a chance of snow Thursday as an upper trough passes.
Original discussion / Thu 4 Feb 2010 / 4p.m.
Another shot of wintry cold continues to show up in both the GFS and EMCWF models (two of the primary ones I use) for next week. The agreement between them has been quite good since Tuesday on the evolution of this event. Also, surface air temperatures are very cold in northern and central Canada to the tune of -20 to -30. This lends further credence to the model solution.