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Would be awesome if the actual blocking turns out more robust and longer lasting. I would love a December 09 event this way And to make it even better................. to happen near Christmas.

Extreme + PNA on the way it appears. Euro supports it as well. Question is the eventual evolution in early to mid December. Inland snow then a more significant event somewhere in the East.

Yes, that is true. Several mets and pros have mentioned a period in December when the NAO may drop. There is also a huge wave breaking event getting under way as well in the North Atlantic. This may have implications in the NAM domain as well . As mentioned here by Simon:

Interesting change today, with the caveat needing to see consistency in the next week, however, a nice drop forecasted in the AO domain.

Would love to eventually evolve the pattern change to a possible - EPO as HM mentioned recently moving deeper into December.

Exactly, anyone thinking snow in early December with a well above average source region is grasping for straws. As CAPE mentioned maybe the real deal, if we ever get one, is when Canada chills down through cross polar flow / - EPO later in the month of December, or beyond. Not sure I agree with Eric Webb about the South getting snow in the depicted pattern outside of the higher elevations. There was always some hope December may deliver by being a shoulder month with a less strong PV. ( But, hey it really is strong currently so... ) Also, there are signs zonal winds may decline later in December. This may assist with HL with blocking, along with a couple other factors.

As expected the weeklies have some major changes. ( for the better )

As we exit November and head into early December. I like !

A few things set in motion during the next week or so...... impact early to mid December for us.

When Anthony is interested you can't help but to be more hopeful. At least a December torch seems unlikely at this point, well at least until the 22 nd.

Some continuing signs this morning that we might be able to achieve a more blocked regime later in the month, and especially in early December. Also, some indications regarding higher pressures building into and near Greenland early to mid December. We all know the odds and the accuracy within the NAO domain, but well worth keeping tabs as we get closer to the holidays.

This is interesting, especially the what occurs after the first of the year, when the favored MJO phase(s) tends to change. This seems to be related to the Nina peaking in the OND period and then waning thereafter.

Expect the unexpected ..............

Let's re-visit this forecast in early December.

Not that it matters much, because the source region ( Canada ) is very warm at this time, but do you buy the + PNA look in early December? We are indeed getting unusual responses and progressions currently, as you mentioned. It will be fascinating to see what the pattern brings us in Jan and Feb where the majority of the seasonal consensus is little snow and much above normal temps. Hard to fight the warmer persistence whether from Nino or Nina like background states. But, I would still keep an eye open for the unusual outcome, in this new unusual climate recently.

Recalling last winter where robust West Coast ridging was forecasted a few times, only to breakdown or never develop, due to the compressed and rapid jet stream movement, culprits already discussed last year. But, if we can get a great Pac pattern in prime climo that lasts a week or more, maybe we can score. Watching the seasonal progression of shorter wave lenghts should be interesting as well later in December.

This does echo the thoughts of Isotherm's seasonal. We wait and watch. At the least the +PNA may help us from torching if indeed it develops.

@CAPE speculating that even if we get a +PNA what about the cold air source? If the EPS is correct Canada is very, very warm. Remarkable, and a sad situation for cold and snow lovers in the East. .

Mentioned the Pac wave train yesterday, and here you have the transition to a +PNA . Today, as you mentioned, more evidence of a + PNA , granted over 600 hours away, but plausible.

IRI update. Maybe some minor implications.

Pacific wave training getting under way soon. If you freeze the animation posted by Anthony you will see the Western ridge amp up and the East Coast trough response near day 9 to 10. I would cold expect a cold period lasting a day or two near the very end of the month. Euro not as thrilled so far. Afternoon run coming up shortly. Keep in mind the same trends as last Fall and winter may once again prevail this upcoming cold season which are the inland runner and Midwest/ GL cutter outcomes.

You can hibernate for the next 10 to 15 days because things look super boring in regards to the weather. However, some interesting developments with regards to SHPV and the NHPV. Currently an extremely cold Southern Hemispheric PV , while the Northern PV is ( quoted by Simon here ) " 100 hPa eddy heat flux averaged over the last 45 days is approaching the 10th %ile in the Arctic " As mentioned yesterday the fires in Aussie and the Western US fires may be responsible here to a degree, as is the QBO. HM mentioned the warmth between the two PVs and the role of aerosols and spoke about a volcanic winter similarity I believe. In my opinion we are witnessing the effects of the change last year with the behavior of the QBO along with the QBO's induced thermal winds manifested upon the aerosol released event, whether acting in unison or separably. Here are a couple great threads that talk about this. One from Dr. Amy Butler and the other from Simon Lee. Each thread is worth clicking on and scrolling through. And for the time being, nothing to be encouraged about. We may be entering as well something called a polar vortex intensification (VI) events https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2005JD006302

Overnight models back to warmer for late month.

25 degrees here, with a heavy frost. Coldest air mass since the end of February around these parts.

Simon's GEFS 35 day regime forecast does show some indications of a shallow regime change coinciding with the early part of December. In my opinion a temporary cold period such as the one currently might be in the cards. AO drops in the days ahead , possibly towards neutral, as the SPV remains strong well above the ERA5 mean.