Weather Models Change To Colder Mid Month But????
This is the 3rd GFS run in a row showing a mid month pattern shift. I hesitate to use the words pattern change because apparently they are misunderstood by some so let me make this clear. When I say pattern change, I mean exactly that. It does not necessarily mean colder and snow. We saw the pattern shift last week to a “split” flow which is now allowing for storms to come in from the Pacific in the subtropical jet. This has indeed happened. What has not happened up until now is a change in the profile over the northern areas of North America. Apparently people don’t actually read my posts so they make assumptions and then make general comments. They succeed in pointing out the obvious in that they just don’t read the posts at all. If you have gotten this far, then clearly you are not among the guilty parties I speak of and we can go on from here. At least I got that off my chest.
Now back to the weather models. There is one thing that sticks in my mind about where we are in terms of the overall look of the atmosphere. The el nino dominant pattern we have been in is now nearly 7 weeks old. I am measuring this against the cold blast in mid October that occurred until today. It has been my experience that when the atmosphere locks into a certain look, it can last 6 to maybe 8 weeks. This one is now getting pretty long in the tooth and a shift is in order. Bear in mind that the pattern could change into something that you may not like and that works both ways. I have no idea where this is going to wind up in the end. We can only follow the road and see where it takes us.
Above is the day run European and the overnight GFS run. The maps are 12 hours apart but you can see that they are pretty similar here. The gfs this afternoon was different is a lot of ways from the European but now it lines up pretty well. Both have the clear problem of the polar vortexes near the north pole on both sides..Greenland and Alaska. Both show an active subtropical jet. Both show some ridging in the east. Okay so now going forward from here and since we can’t see the European beyond day 10, The GFS shows the beginnings of a breakdown of the arctic configuration.
The GFS creates a monster Great Lakes Storm (970 ish millibars) which essentially becomes the mechanism that rearranges the pattern across North America. From here we jump ahead to the end of the period and wind up with this!
This is out at day 16. This is a completely different look from what we have now. Cold air has a pathway to drain into the United States. Ridges are in semi favorable positions to hold this in for more than a few days. Vortexes in the north have regressed westward in the case of the Aleutian low and northwestward and away from Greenland.
I’m going to say right now I am highly highly skeptical of this and by the time you read this, the next run will have been out and it most probably will look completely different. It seems to me that this is all predicated on that big Great Lakes Storm that is shown for around days 11-12. If that is not real than nothing that follows is real either.
At this point let me leave you with this. Something is going to give soon. I pointed out yesterday that perhaps what we will see is some sort of transitional shift away from the el nino dominated pattern we have been in, and that we will go into a more volatile pattern as we move from mid December until the early January before we lock into something else. I have no idea where this is going or if it’s going anywhere at all. Later today I will evaluate the other weather models as well as the next run and see if any of what was shown tonight has any value.