...I could blog about the specifics of the storm and what it did and didn't do and have a really, really long reading. But I won't this time.
But I do want to remind everyone that weather systems are not a solid object that can be coherently tracked from one location to another. Weather is NOT one dimensional and is NOT a solid, but rather is 3D (can argue it's actually 4D) and is a fluid that changes continually. There are around 100 tredecillion (that is a 1 with 44 zeros) molecules that make up the atmosphere. Computer forecast models attempt to track some of these molecules that are governed by such things as Newton's 2nd Law of Motion, the Ideal Gas Law, Equation of Vertical Motion, Equation of Continuity, First Law of Thermodynamics, etc, etc.. Expert Meteorologists are forced to absorb a torrent of information to make predictions as accurate as possible. That is dealing with a small fraction of the 2.5 quintillion bytes of information that is generated each day - the equivalent of the entire printed collection of the Library of Congress about 3 time per second.
Like a baseball umpire, a weather forecaster rarely gets credit for getting the call right. So be it.
Go back to posts I did during the late fall. I had concerns that the "El Nino" would not benefit California until later in the winter. It looks like that is finally starting to happen. I can argue that this past Christmas weekend storm could have been influenced heavily by the beginning of these changes.
Looking at the afternoon satellite image...
The upper air flow has recently become chaotic. There is still flow across the central U.S. with minor disturbances that will likely keep cloudiness across much of the area for a few more days. There was a disturbance (the X across western Canada) that was dropping south that will intensify but should get cut off and meander around the NW U.S. for a while. The reason it will cut off is the split in the jet stream that is developing (likely because of the strong south to north jetstream that has developed out of the tropics and into Alaska).
The significant changes
There is a new East Asian jetstream that has expanded across the Pacific, but this time much farther south! The reason for this is a VERY robust Madden Julian Oscillation (MJO). In fact, looking at a phase-space analysis of this MJO, it is 2 1/2 to 3 standard deviations above normal. Unreal and significant! Here is that chart...
At the same time the Arctic Oscillation is forecast to crash (maybe in the wake of the very temporary storm going through that region raising temperatures)?
So what does this all mean?
The nature of the weather pattern generated early this fall from different source regions forcing the jet stream into a cycling pattern, is set to favor the jet stream to dip into the western U.S. again. The first evidence of this will be the East Asian jetstream that will bring a significant precipitation event to all of California. Look at the prediction from WPC...
This system will move out into the central and southern plains late in the weekend or first of next week, but will also be weakening as it does. There could be a bit of light precipitation for the high plains but it should not be too significant. I've been expecting a pretty strong storm sometime afternoon the first of the year for some time (centering on late in the first week). With all the changes going on across the Pacific and with the timing of the pattern, there may very well be a decent storm somewhere around the 7th (give or take a few days). Nothing is really showing up right now, but that may be changing. I won't have a chance to post here until probably the 3rd or 4th, so check back then and I'll update on the prospects of the possible storm AND a turn to sharply colder by mid-month.
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