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Looking towards the beginning of December


CoastalWx

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There are a few things to look for here...

The Branstrator wave in the North Pacific, which is a 20-25 day retrogression cycle, has implications on circulation. If it were to work out as modeled, we would be looking at an Aleutian Low / Split Flow / PNA development sometime in the first half of January. There is also indications that if the Tropics continue to follow their patterns that the MJO may try to come alive as we move into the New Year. This would also fit with analog data, solar data and the North Pacific changes to some extent (feedback from retrograding N PAC low). Currently, the Tropical State is very similar to mid-October but the East Asian Jet has been very persistent along with the West Pacific stagnant forcing / Hadley Cell. These features combined with the IO forcing are basically disrupting any waves currently, but I don't think that will remain the case as we head into January.

As the big Aleutian High in the stratosphere begins to stretch out the "surf zone" and the high PV anomalies become stretched, cooler air will be displaced to the equatorial regions mid to late December. This may mess with organized stagnant circulations and allow assistance for the MJO. Finally, the solar factor will also be dipping again late December.

It's funny, I googled "Branstrator north pacific retrogression" to try and turn up some research, and the first results were three eastern us wx threads from the 08-09 season..one of them was this post of yours from december 20th 08, titled "the failure of the -NAO". We eventually got our -NAO block early Jan of that year of course.

http://www.easternus...ure-of-the-nao/

Edit: further down in that thread there is a solid 2am bromance reply by me as well...definitely was blitzed that night :lol:

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Well that may be indirectly related while something else is possibly forcing it there from the other side of the NH. Then of course last year the vortex was pushed to Greenland with a SSW and it meant nothing in terms of the NAO (but the AO was in the tank).

Solar forecasts say general smooth peak 12/16-12/17 so that will give a slight positive tendency to the annular modes and La Niña-like GLAAM. The exact way the sun affects things is of course in theory so I wouldn't get to bent out of shape over it. Also, forecasting techniques are in the dark ages in terms of the sun, especially when compared with our own atmosphere.

Yeah honestly the cool anomaly near greenland is not the focal point of that research/correlation map he produced anyway. The whole concept of it was November/early winter having the warmer than normal 70 mb over Eurasia, likely as a result of the SAI in relevant years. The cooler anomaly over greenland on the map is likely just a byproduct of the fact that the vortex has to displace somewhere, I'd guess...

I cant find the 70mb image he generated, which had a better correlation, but I did have this 20mb image saved..the anomalies are similar, and this is of coruse what you do not want to see for a -AO Jan this time of year

post-402-0-67492000-1354300940_thumb.gif

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