Update 11/7/2016

This weather pattern is getting rather complicated and confidence during the next 1 to 2 weeks is low but the picture of what is beginning to happen is becoming a little clearer.

First, in the post I did on Halloween (read it here) there was a lot of information shared. One bit of info was about a weather system that was off the west coast.  It was not clear how it would track but there was a pretty decent chance that it would bring precipitation to the plains.  I initially thought (in the previous post to that one done on the 28th) that the most likely time frame would be the 2nd through the 5th.  The system did arrive and bring showers and a few thunderstorms, just a few days late.   Here is a map of rainfall during the past 48 hours ending at 7 AM this Monday morning (11/7):

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Unfortunately, there were quite a few locations that got a measly amount of rainfall.  But there were many areas, especially across eastern New Mexico, west Texas and the panhandles that got a soaker.  For the remainder of today (Monday and into Tuesday) there will be a bit more.  But then the bad news.

It looks like the pattern is starting to transition into a colder one, albeit for a brief time.  Plus, the prospects for any additional moisture for a little while is dismal. 

In the previous posts I was anticipating an abrupt end to summer, by November 10-15, expecting a widespread killing freeze.  This will partly be correct.  As dry air settles in over the area, it does look like radiational cooling will be enough to get the mercury down to below 28 degrees for many areas (just not everyone) on the morning of the 9th.  Here is a map from the National Weather Service showing their expected lows for Wednesday morning:

click for a larger map

 
But what I had been expecting by the 15th was a strong storm coming over an upper level ridge and diving into the central U.S., bringing a "real" shot of cold air and perhaps a storm with perhaps snow.  At the current time it looks most likely that this will occur for the eastern part of the country, and not here in the central part of the states.

Here is the satellite image from today:

First the red X over Kansas (far right center).  That was the system that brought the rain, but it was being adsorbed into a transitioning upper flow as of Monday afternoon.  The squiggly blue line across the west coast represents a very strong upper level ridge.  That is actually in a very favorable position to allow systems riding over the top to dive south and southeast into the central plains.  There is the "X" over the southern coast of Alaska and more importantly the "L" over the Gulf of Alaska.   This system is VERY strong and moving northeast.  What I thought might happen is it would move into western Canada and then dive south and southeast into the central plains as it got past the ridge.  This could still happen, but no computer model is forecasting this to happen.  Instead it should slide southeast into the eastern U.S., and could bring a huge storm to the eastern seaboard or northeast.  Regardless, the system will help to draw down cold air into at least the eastern half of the country (and perhaps as far west and western Kansas) by the weekend.  This "could" be enough to bring a killing freeze to the remainder of the area that doesn't get it Wednesday morning.

Beyond the weekend, there are a few interesting pieces of information.  First, the snow cover across Europe and northern Asia continues to grow:  Compare the latest snow cover map to the previous ones I posted:

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Correspondingly, surface temperatures are quite cold across a large area:

 

Where is the excuse to get this cold air across into this side of the hemisphere?

Well, let's look at a satellite image of the western Pacific:

You might recall in the last post on the 31st that I discussed the upper flow responding to a developing Madden Julian Oscillation (MJO).  There has been a very coherent response from the tropics into higher latitudes.  The most notable was a HUGE upper level ridge that has developed across the central Pacific.  This "could" dislodge the cold airmass over Eurasia and begin sending it/building it into much of the Arctic region (on our side) and northern Canada.  If it doesn't happen in the next 7 to 10 days, then I think it's almost a slam dunk to happen by the end of the month.   This ridge position is also in a pretty good location and amplitude to help it get stormy in the central and eastern U.S. (the first of which should be by Saturday the 12th on the east coast).

Beyond this coming weekend, if the MJO continues (and it should) then based on composites of MJO activity, the central U.S. should become quite cold by Thanksgiving and into the first week of December.   This would also serve as a catalyst for a significant storm to develop (Thanksgiving week?).  Also, hopefully by Thanksgiving, the cycle length of this years pattern will start to become clear.  Once it does, I'll have a better understanding of what will happen through the winter months and into spring.