It's still going on. The trouble with it is, much like the angular momentum stuff, MJO , stratospheric wind weakening, ENSO, sunspot numbers, the AMO , QBO and so forth - it's just one piece of a much bigger puzzle, one which nobody - nobody - understands fully.
One of the chaps who frequents NW (which has always been the place to go to see buzzwords) posted this back on the 3rd Dec, on X:
As expected we have a +EAMT event underway. Essentially, +Mountain Torque takes momentum from the earths orbit & dumps it into the atmosphere, in this case, the Pacific jet. The jet extends east causing large wave-breaking events which ripple downstream. LATE DECEMBER COLD!
https://twitter.com/Met4CastUK/status/1731386899506348218
EDIT: And tying with BJBlake's post above, it's my view that if you view each of the things I've mentioned above as a switch, on or off (in our favour or not), in the 60s to 90s you could get cold weather with just a few switched on. These days it seems to take pretty much everything switched on, and that very seldom happens - or, in more scientific terms, we're constantly moving right on the bell curve, meaning a 1% chance becomes a 0.5% chance, a 0.1% chance and so on.
I'm still intrigued as to why we don't get Scandinavian Highs in midwinter any more. Clearly something's fundementally changed, presumably due to the warming trend, but it's odd. Maybe eventually once warming continues apace they might reappear, as whatever's blocking them from forming moves even further north?
We still see them modelled from time to time, although usually as a one off event, rather than the self-reinforcing, repeating version as seen in the last Scandinavian High outbreak, in 2005. It's why it's even harder to get them - not only do we need one to form, we need the rest of the pattern in our part of the world to enter that self-sustaining mode. It can do it, effortlessly, when it comes to the Azores High, of course!
Originally Posted by: Retron