Monday, November 14, 2016

Monday Morning Weather Discussion: Knocking on Winters Door

Good morning. As we have been patently waiting on what this winter season will entail, more details are emerging by the day. I mentioned in my last video how models are really struggling to figure out this seasonal transitions and forecasting the long range would need to include a variety of methods as a result. I also mentioned that we need to see winter develop in December this year based on my winter forecast. Today I am gaining confidence that process is continuing to evolve.

Here is a summary of my post below:


  • Tranquil upcoming few days is followed by a storm system that will sweep across the country later this week
    • Snow will fall in the northern plains and New England might also see some snow Sunday night if this system redevelops off the coast.
  • Following this storm, the flood gates begin to break towards colder and stormier weather from the Thanksgiving through mid December time period
    • This idea which was first proposed in my winter outlook is gaining support in model land
    • Seasonal drivers such as a negative arctic oscillation and negative north Atlantic oscillation  are projected to develop as we end the month which supports this idea
  • The pacific jet stream will continue to influence our pattern but other factors will offset some of its effects. 
    • Translation: a lot of back and forth weather is to be expected which should continue to be the theme as winter progresses
  • First snowfalls for many areas can occur by mid December.

So lets dive in and take a look at what is currently going on..


A big storm system is expected to drop snow in the northern plains midweek...


This storm will run into a lot of high pressure over Canada which will cause it to slide east by this weekend. As this occurs left over energy out in the Atlantic from a previous system will try to consolidate with it. This all can occur because the jet stream will be "blocked" in the Atlantic. This means that an area of high pressure causes it to buckle and slow down. I show this below..


This results in a possible redevelopment of a storm off the east coast which could result in interior snows Sunday and Monday..


In the wake of this storm system, things look like they really want to start waking up the week of Thanksgiving. We have an atmospheric pattern developing which will feature a lot of high pressure over the pole and Greenland (-AO and -NAO). When a pattern like this occurs cold has a better chance of filtering down from the pole into North America. Combine that with a pacific jet stream that still wants to stay active and you get a battlefield of weather over the United States. This means a lot of energy comes into the  united states and has the chance to combine with cold air. 

The image below shows what I am talking about..



This image shows cold and warm air (blue and green). This illustrates the potential for cold air to filter down into America and storm systems to develop as Pacific energy interacts with this cold air. Now if the Pacific influence is too strong it overrides everything else. However, if we get the right mix of cold air filtering in from the pole and with a low to moderate pacific influence then we will have a lot of weather we will be tracking.

Just for fun here is the long range GFS showing what a pattern like this can result in. I would not take this literally and understand this is just for illustration purposes..

Notice a lot of energy on the field with multiple storm systems. As we enter December I would not be surprised to see a pattern similar to this develop. As long as we keep the pressure high over the pole and Greenland, in my opinion it is game on!

Long term models hinting that will occur as seen with the red colors below. This matches the expectations from my Winter Outlook..


If we get that to maintain itself into December......


Thats all for now more will be coming this week. 

2 comments:

  1. I am gritting my Teeth and biting my fingernails on what this pattern means for Elmira/Corning/Binghamton NY regions. If I go by what has happened for many winters now, it means we will miss significant snows for one reason or another. Cold and blizzards have setup in Europe already. Meanwhile, I'm still cutting grass, with an expectation of having only a flake or two of snow this winter.

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    1. I do not think you miss out this year. If anything you will do better than areas that got more snow than you last winter. Be patient, the pattern looks to be turning here. We will see what happens

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