The pattern

 A look at the pattern as we close out November and going through December.

November here in the eastern half of the United States started out very chilly, While at the same time it started out very warm out west. In the winter outlook I said winter would likely start early this year, So far  that has certainly been the case as we have been dealing with abnormally cold temperatures and many of us have seen snow start earlier this year than the last several years.

Let's take a look at the current pattern signals.

Global sea surface temperatures

Image credit tropical tidbits

The El Nino Southern Oscillation

The latest SST observation indicate that we're definitely in a weak La Nina in nino regions 3 and 3.4

The Quasi biannual Oscillation. 

I've been talking about the QBO for the last several weeks and how it being negative is a strong indicator for a cold pattern. 

The Madden Julian Oscillation

The pattern that we're going to be dealing with over this winter The MJO is going to be an important factor when it comes to short-term variability. The MJO is also most likely going to be the main driver of our winter pattern.

The MJO is currently in phase 6 and looks to remain there for a few more days. After that it will move into phase 7 closer to the end of the month. This is going to have implications on the pattern moving forward.

The current Sudden  Stratospheric Warming event. 

This SSW looks to peak over the North Pole around the 28th to  November 30/ December 1. This would mean the stretching of the polar vortex could reach the Northeast and Middle Atlantic five to maybe seven days after that. 

So the last couple days of November into the 1st couple days of December Could end up being  average to slightly cooler than average. But after that some real cold is going to work into our region. 

As I've been saying, were in a strong negative (easterly) QBO, This current configuration means there is a good chance for several disruptions of the polar vortex as we move into at least the 1st half Of this winter.

But with the negative PNA, this would mean we have a shot at some warming for the end of November at least in the Middle Atlantic. Also, with the MJO loving into phase 7 we could end up seeing those warmer temperatures that are currently in the central part of the country, to at least try to move east. I know I have been talking about November ending on a cold note. But the MJO is saying hold your horses and let's not get too premature!

Based on the current teleconnection signals I think we are going to see some warmth as we head towards thanksgiving and a little bit past that. This would be good news for those who are traveling to see family during Thanksgiving. Then the last 2 or 3 days of November into at least the 1st half of December, We're likely to see a significant pattern change start!

Looking at the graphics from NOAA. They are seeing the same thing and confirming the cold that's on the way as we head into December 

The general December pattern is going to be Based on the combined effects of the current La Nina, the Madden Julian Oscillation and the potential for that November sudden stratospheric warming event. 

Based on what looks to be happening once we get past the first 2 to 4 days of December The region should plunge into very cold temperatures. That should be averaging well below average for December. The December pattern is still looking to stay very active. Similar to what we've been seeing. But with the cold air in place and looks to have quite a bit of staying. But with the cold air in place that looks to have quite a bit of staying power at least for the month of December will most likely be very snowy. We're likely going to have our first major regional storm before Christmas. Will this mean we're going to have a White Christmas? While we will have to see I do think the odds of that happening for the vast majority of us is looking fairly good. But I guess time will tell!

As I said in the winter outlook, I think the same general pattern is going to extend into January. based on everything setting up during December into at least the middle of January. I think the region is going to be very surprised with the amount of snow we end up with during that time. The pattern I talked about the winter outlook Looks to be the one that's evolving and I think snow lovers are going to be happy overall with the way things are gonna go