Good morning bloggers,Before we get started, I would like to thank all of you for yesterdays discussion in our blog comments. It was potentially one of the best discussions we have ever had in the blog for multiple reasons. It was respectful, open, rather full of interesting information, and it is worth reading through again. I would like to thank you so much for helping us create this great forum for us to express our thoughts, and for providing your own insights where we can all learn something in this positive environment. Go through and read yesterdays comments if you get a chance. Many of the bloggers came through big time.  Okay, onto today’s blog!

While Kansas City is in a three-year plus snow drought, as it has been four years since our last 3″ snow storm, snow is likely in Mexico, and rather wide spread snowfall. And, it may snow over the deep south later today and tonight.

This map above shows snow over a large part of northern Mexico by 6 PM this evening. This wet storm system is then going to track across the deep south with a cold rain, thunderstorms, and some snow that may fall in cities like New Orleans and Atlanta.

While a half a foot of snow is likely over some of the higher mountains of Mexico, Kansas City hasn’t had six inches of snow in one full season since the 2014-2015 winter.  And, that 14.1″ of snow season was still well below average and it came in around 17 different snowfalls, for an average of less than one inch per snowfall:

There are some big changes showing up on the models. The blocking ridge out west has been so strong. It has also created the conditions for the offshore flow over California where the fires are devastating many areas around Los Angeles.

The blocking ridge continues to strengthen near the west coast of North America. This map above shows the forecast valid on December 11th. This system is called an anticyclone, or the opposite of what a storm is called, cyclone. This anticyclone is broad and rather large. As we showed a few days ago, this ridge is right on schedule according to the cycling pattern.

This ridge forming and strengthening in the next few days is directly related to what happened in the first LRC Cycle 48 days earlier.  According to the LRC, the pattern evolves in the early fall from October through November, then it repeats. One full cycle likely lasted from around October 6th or 7th (considered day one or two of the first cycle) through around November 22nd to 26th. This first cycle is now repeating. So, what is likely next? The eastern North America trough should retrogress with a “flattening” of the jet stream to more zonal.  This is now finally forecast to happen by most of the recent model runs. Here is the European Model from last night:

The ridge is forecast to drop southwest to off the Southern California coast by the middle of the month.  While all of this is going on, the pattern remains almost completely dry in many areas that are now in rather long dry spells, of which Kansas City is one of these locations.

Precipitation Forecast Ending December 20th:

As you can see above, the area from California east to St. Louis is almost completely dry for the next 13 days. This is a disturbing trend, but let’s see  how this evolves/cycles in the next few weeks. It can’t stay this dry, can it?  Those 17 days of potential stormier weather will also be cycling back through in January.  This 17-day stretch was wet in October, in cycle 1, and it has been dry in late November and December, in cycle 2. We will be testing this big time in cycle three. For now, it is about as boring as it can be near KC. But, not in Mexico or the deep south.

Thank you for sharing in this weather experience featuring Weather2020 and the LRC. Have a great day!

Gary