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Pattern December - Deal or No Deal?

the warm ground and surface temps being marginal is likely gonna cut back on accumulations but I dunno... I could see a small area getting dumped on, just impossible to tell where. Heavy rates+nighttime should at least briefly be impressive

but lol the TV met was showing models on air and showed the NAM and went "oh my god the world is ending"
 
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That SSW isn't going no where until something from the northern stream drags it out from Mexico/Baja CA. Perhaps, a piece of energy will come down east of the Rockies and take that SSW with it.
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Euro is all like what snow here lol

Had an 8+ inch bullseye last run to my SW:rolleyes:
 
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The good news is there’s plenty of time. For a storm to pan out around Christmas. Christmas magic happens it did in 2010. And it could happen again.


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The overall pattern looks favorable leading up to late December for a potential Sudden Stratospheric Warming Event in the form of a wave 1/displacement event with troughing dominating the Bering Strait & Eastern Siberia and a huge high over Scandinavia, both of which are projected onto the standing planetary wave pattern and will increase wave forcing onto the polar vortex, decelerating the polar night jet, and leading to considerable warming in the polar stratosphere.

The question becomes how significant is this warming, does it actually perturb the tropospheric vortex enough to give us a prolonged period of high-latitude blocking in January & even February, and how will tropical forcing (the MJO esp) evolve in tandem w/ this potential SSWE?

The answers to all these questions are still in the air atm, the MJO's amplitude may increase in a few weeks time though given the polar stratospheric warming that leads to acceleration of the Brewer-Dobson Circulation, ultimately affecting the shear & static stability of the tropical tropopause (in this case, cooling it and thus being more conducive to near-equatorial convection), and typically it takes a few weeks for the tropospheric vortex to significantly respond to a sudden stratospheric warming event like this unless the warming is initiated in the troposphere first, thus I wouldn't anticipate this to really have much of an effect on our pattern until early-mid January.

Until then, the tropospheric vortex will leave North America and migrate towards Siberia, temporarily exhausting the North American continent of cold air. However, as the vortex digs towards Siberia, it will induce downstream ridging in the NE Pacific and Alaska, (-EPO), which will then reload the continent with cold air and create a pattern we've come to all know & love the last several years in the southern US, giving us a favorable look for wintry weather in the southern US yet again as early as the last week of December, with the SSWE potentially influencing our chances in January & beyond perhaps.
 
I’ve never seen so many storms popping up back to back before like this on the models. Craziness.


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