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Will not show the whacky GFS

I see that in the modeling. Interesting I read the event was more of a reflective manner, and did not couple the SPV and the TPV. Of note is the current AO which despite Canada, and basically a large portion of North America cold, the AO has not dropped. Wonder if that changes going forward. I looked a couple days ago and believe long range modeling has the AO going negative.

Here is the ext

Looks so pretty. The weaker PV presently, and the MJO progression, along with increasing Atlantic blocking associated with the general background state actually support this cold and possibly snowy look in the East during December.

The 10 th does have real potential as you mentioned. Beyond that date things still look good for cold and snow potential.

I would like some energy to arrive near mid December from our SW with cold air in place. Webb talks about a Nino like period possibly. Eric Webb @webberweather The ongoing MJO event in the West Pac has led to a *gigantic* build-up of westerly momentum (+U) in the tropical troposphere, w/ GLAAMa approaching +3 sigma; very El Niño-like. Eventually, some of this tropical +U will get injected into the mid-latitude storm track Eric Webb @webberweather 46m Very high +GLAAMa like this coupled with our La Nina base state is not exactly favorable for western troughing/-PNA & I expect this to remain generally the case thru late Dec or so, even tho the Euro weeklies are trying to argue otherwise.

So true !

What are your thoughts here ? ( bolded part ) Tomer Burg @burgwx With the addition of the AIFS ensemble, I've also added plots comparing the EPS to the AIFS ensemble: https://polarwx.com/models/?model=comparison Some major differences emerge between them heading into the 2nd week of December, with the EPS colder than the AIFS in the eastern US: Differences between the EPS & AIFS ensembles are largest over Alaska, with the EPS showing a deep cutoff low over AK reinforcing western US ridging. The AIFS ensemble does not explicitly show such a strong cutoff low, but also has larger spread in 500mb heights than the EPS.

The ECMWF AI really cut back on the snow totals further South, and seems to have a cold bias. I thought I read here it is only useful with 72 hours of an event. Not really sure about that though. What have you noticed?

Paul Roundy @PaulRoundy1 The west Pacific warm pool is changing shape. Eventually it will allow for more convection near the Dateline, which can favor western N. America ridges. Paul Roundy @PaulRoundy1 38m If the western ridge is far enough west, it can favor a central N. American trough and eastern ridge. 1997 Feb-Mar had eastern US ridging in spite of central Pacific convection.

I like this slow movement.

I believe @GaWx had a detailed post about the benefits of a favorable phase(s) closer to the COD, versus high amplitude.

The AO remains positive, but we have intense cold in Canada and a weak PV. The MJO and the general progression could show potential Dec 15 th to Jan 5 th for the East Coast. >>>

World Climate Service @WorldClimateSvc Quite excited about this: MJO forecast from the AIFS-ENS, including an in-house 28-day extension. Preliminary skill results are *very* interesting. Available soon to customers.

Interesting, past times when we had a warming.

Oh my, the SER is taking a vacation. Ensembles playing catch up as well.

That progression would at least tend to help us based on the opinion of many mets. I did not see Don's post. However, I read here it was using some of the forecast data from the ECMWF weeklies which I do not trust. They can be wrong, and the last two winters when bullish on cold and snow were terrible. So I feel them showing increased warmth can be incorrect as well. JMHO.

Looking better, and hopefully other data in the next week will point to the MJO getting into phase 8 at a lower amplitude, and then enter phase 1.

SER shifting SE. Modeling has certainly trended to colder outcomes in the East and the SE. .

Another day of clouds here. The forecast was for mostly sunny. But, so far 90 % of this day has been mostly cloudy. A theme the last 10 months.

Interesting AO forecast. Lots of spread, and not like the last two years. The strat warming( CW ) not influencing the AO, by a lack of coupling. As mentioned later in this post, in 1958 and 1968 they did couple but several weeks later. Giuseppe Petricca @gmrpetricca 47m Today's zonal GPH chart gives us a good example of uncoupled/limited coupling tropo-strato in the forecast. Strong stratospheric anomalies are present in the 10–50 hPa layer (and above - red rectangle), but below 100-200hPa, the situation is different, with limited vertical coupling (blue rectangle). While the stratosphere maintains a persistent positive anomaly pattern, at least until towards the end of the run, these signals do not propagate downward in a way that would typically influence lower-level circulation (for example, look at the orange/red anomalies back at the start of October, where they covered the entire column). In the troposphere, anomalies remain more variable and horizontally confined, indicating that the two atmospheric levels are acting more or less "on their own".

From https://x.com/judah47/status/1992608265507946858 Seems very reasonable. Third week of December looks good.

>> For comparison. >>

If only the weeklies were correct for once in the super long range. Nice look mid to late December.