posted on Dec, 12 2012 @ 06:21 PM
I remember reading some forecasts for this winter back in Sept. talking ab out the Arctic Oscillartions and of course La Nina, having a negative cycle
this year and how it would affect the weather.
The latest things I can find talking about it are here:
posted back on Nov. 25th.
And then there is Dr. Jeff Masters Wunder forecast.
Posted back in
The first link, makes a lot of sense as to why we are not seeing so much of the cold and snow that was predicted at the end of Summer and the
beginning of fall. We aren't getting it yet because there is one more thing that is suppose to happen:
Let’s take a look at some of the weather models as we move into early December and we can see there a lot of other very important features to
consider besides a strongly -AO. This next image shows comparison between the operational European model at DAY 9 on the left side and the operational
GFS model on the right side. We can see several very important features but the most dominating one happens to be the BERING SEA OMEGA RIDGE . (for
those of you that do not know the Bering Sea is the body of war to the separates Alaska and far eastern Siberia). It is this feature which has been
persistent now for about two weeks which is the dominating or driving feature across the western hemisphere and not the AO. The placement of the OMEGA
RIDGE over the Bering sea means that you have to by definition have a trough in the jet stream over Alaska and Northwest Canada. That trough
constitutes a POSITIVE PHASE of the EPO and therefore -PNA pattern ( West coast Trough in the Jet stream).
In order to get this pattern to change the strong OMEGA Ridge in the Jet stream over the Bering sea HAS to move to move.. HAS to. In doing so it
will force the EPO to switch from +EPO to -EPO… and that in turn will allow for a strong west coast Ridge ( -PNA to +PNA) which sets up a much
colder pattern and allows the trough to form of the eastern U.S.
So if I'm reading this correctly, this OMEGA Ridge has to move in order for the normal (or colder) weather patterns we are used to seeing to set up
(cold temps and air diving out of Canada, Clipper snow storms pretty much burring Canada and the northern tier states).
So that's what we're waiting on I guess. I know here in SC it was really warm (into the 70's) for the last few days, and now the temps have
plumeted with lots and lots of cold rain all day today (and into the night tonight.). That's pretty typical for us here during this time of year.