MORE HINTS/ REASONS WHY I AM SKEPTICAL OF MILD LA NINA WINTER NARRATIVE
This image has two different maps for your consideration. The image on the LEFT shows the snow cover over North America as of November 5 from 2016. As you can see the snow line was significantly further to the north then it should of been for early November in Canada. Typically the snow line is usually near the U.S. Canada border by late October /early November so this was unusually far north even for Canadian standards. It was also a sign of trouble for the winter last year.
The image on the RIGHT represents the latest snowfall map a for North America as November 5 2017. As you can see it is MASSIVELY different in every possible way. Not only is the snow cover much further to the south the last time the snow cover in early NOV was this far south was NOV 2103. In addition the snow cover is also significantly deeper along the U.S. Canada border north were that a typically is in late November.
This GRAPH shows the snow cover in North America EXPOLDING off the charts when compared to the last 20 years
BIG DEAL -- SO WHAT ?
As many of you know the cold or arctic air masses which reach the central and eastern U.S. originate from Canada. The area known as the North American icebox is western and southwestern Canada. Depending on the weather pattern of course the cold air can enter the U.S. at various locations Sometimes the cold air can even cross over the Rockies and move down the West coast into Seattle...Portland ...and into California and Nevada. Most the time whether it passes east the Rockies into the Plains ...the Midwest and the Northeast.
The point here is pretty basic but REALLY important. All of our cold air comes in Canada - duh !!!! This requires that Canada develop early deep heavy snow cover which in turn allows the cold air to build up over western and central Canada in the month of November. Without the snow cover the cold air supply is often significantly weakened. This is the problem we had last winter.
The reason WHY we had this problem last winter was because of the howling extremely strong Pacific jet stream streaking across the north Pacific ocean at near record velocities... bringing in storm after storm after storm and relatively mild Pacific air into Western Canada. The effect was to destroy the snow cover in the month of November and throughout the winter in western Canada ... which in turn kept U.S. snow cover much further to the north and unusually shallow. In other words the supply of cold air which is generated over the snow cover was constantly being attacked and without a significantly deep pool of cold air in Canada there is no way to get the cold air into the U.S..
Why did we have this constant flow of strong Pacific jet stream energy attacking Western Canada and destroying or disrupting the snow cover??
It was the record strong positive QBO values of November 2016 ...December 2016.... January 2017 ... February 2017 and March 2017. It is my contention that the record strong positive QBO enhanced the Pacific jet to such an end exceptional velocities that Western Canada snow cover was disrupted and it ensured that the arctic oscillation would stay positive.-- that there be no blocking patterns in the jet stream and it is these blocking patterns that produced winter storms on the East Coast.
As I discussed MY winter forecast -which I presume most of you have seen -- THIS autumn ? Winter we have a moderately negative QBO values. So instead of +14 and +15 QBO values we have -14.42 in August 2017 -15.28 in Sept 2017 and -16.79 in OCT 2017. It is likely therefore that the QBO values will stay at -20 or a little less throughout the winter fundamentally changes the atmosphere of pattern .
In addition I can tell you that there been some talk from the various weather forums that there is a significant change showing up in the shape of the PV - polar vortex --as we move into the end of November. There are indications of a blocking pattern developing over Greenland which would qualify as a strong -NAO while at the same time a ridge begins to form the jet stream over Western Canada. These two features would force the the mean trough position from southwest Canada into the eastern US / East coast and winter favor east coast winter storm development in December.
This is the European weekly model which JUST came out this Monday evening and you can see it's valid for early December. The strong blocking pattern which we can see on the dark red over Greenland is quite evident.
The second image shows the change in the pattern by mid December and it's quite cold over the Midwest New England and the Middle Atlantic region.
Yes this is a long way out and it somewhat speculative but I believe the trend is going my direction especially since right now the consensus forecast remains for mild winter. The trend is my friend