snowman19

With today’s rain, most areas are saved from the driest fall on record. However, this met fall will almost certainly end up in the top 5 driest falls on record region wide

The EPS playing catch up in the PAC again. While the PDO has weakened since the beginning of November, it is still extremely negative, as is the PMM and IOD. In the Atlantic, the New Foundland warm pool is still going strong (+AMO): The waters in MJO phases 4-6 are still anomalously very warm and that’s the general area where the atmosphere is going to want to fire convection, law of thermodynamics, convection over the warmest SSTs. I think the answer to what’s going to happen once the WWB/+AAM effects on the wave train wears off is starting to be answered. The models are starting to finally reflect an MJO response around mid-December. We are seeing a very positive push in the SOI and are also seeing a very strong EWB in ENSO region 3.4. It is no doubt going to cool (possibly significantly) in December. Very clearly, a “Modoki” event is taking shape. There is also an absence of upward wave flux/warming into the stratosphere and that is going to allow the SPV to significantly strengthen next month. This fits with the -ENSO/+QBO/solar max base state. The saving grace with regard to the stratosphere is that there aren’t any signs (yet) that the SPV is going to couple with the TPV:

IMO some people are being way premature (mostly in twitter land) with assurances at the end of November, that the early December pattern is “locking in” for the rest of winter. Who knows, maybe it does. But based on the totality of everything happening now and has happened synoptically over the last few weeks, I think that may be a really huge mistake to be so sure of something “locking in” and being completely dominant for the next 3-4 months. That’s how you paint yourself into a corner you can’t get out of and lose credibility if it all goes by the way side

@40/70 Benchmark While I firmly believe this period coming up is WWB/+AAM forced, the reality is that it’s not going to last forever. Eventually that WWB/+AAM effect wears off and the wave train will adjust. I’m seeing some folks arguing that the MJO is going to be a non factor this winter and IMO that is not going to be the case. While the MJO is getting muted right now, I don’t think that remains to be the case. Here’s a good discussion:

You were so sure December was going to roast lol

The CFS is a joke. It insisted on a huge blowtorch December for months on end then does a complete 180 the last week. Terrible model

You point out a real important and big difference between now and 13-14, 14-15….those winters both featured a very muted, retracted PAC jet that allowed the pattern to go stagnant and basically remain in place for months with very few, brief and far between interruptions

I think the larger issue is the EPS’s handling of the PAC in the long range. For whatever reason it does a really bad job on the PAC side, has for years and it hasn’t gotten any better. Last year was a great example. Surprisingly, the GEFS has done way better and the EPS is always playing catchup. I’m not really sure what they did as far as the EURO upgrades but it hasn’t helped

EPS and to a certain extent the GEPS (though not nearly as bad) has been doing this in the long range for years now. The EPS is by far the worst at constantly trying to incorrectly weaken and retract the PAC jet and it’s an ongoing issue despite the upgrades

A classic “front-loaded” Niña winter is typically cold from November/December to mid-January then it goes mild. February and into March are usually the “canonical” Niña torch months

I wonder if the RONI stays in Niña territory?

I’m not an Eric fan as you know, but he does have a good point. And it would go along with the ongoing drought cycle we’ve had since August, minus last week’s blip

Would you actually be surprised if this trends way drier Anthony? Besides the one lone anomalous event we saw last week, this has been the same old story since the drought started in mid-August. Status quo dry pattern, minus that one blip in a sea of dryness. It’s been finding ways not to rain for months. I wouldn’t be shocked one bit if December ends up cold and dry @Stormlover74 Take the under on this event. I think this trends drier and drier from here on out

I still think there’s a chance we see a very weak La Niña in region 3.4 by late December. I’m also of the opinion that the current PAC is being entirely driven by the unexpected and very strong WWB. I do not believe we are seeing a full scale change in the PAC cycle like some others do. My guess is that we go back into a Niña-like PAC come late December or early January. We will have to wait until those +AAM effects wear off and the wave train changes before we can know that for sure. If I’m wrong, tear me apart. That said, I do believe a full scale PAC cycle change extra-tropically and tropically (ENSO, PDO, PMM, MJO, Indian Ocean, WPAC warm pool), will be in place for next winter and that change will begin this spring

@bluewave @donsutherland1 While a big curveball has been thrown with respect to the PAC, the stratospheric/SPV progression so far is not conducive to sustained AO/NAO blocking going into December, not that we need them to be with a PAC like that come early December

This EWB is pretty significant and we are seeing 3.4 cooling anew. While a moderate/strong Niña is obviously completely off the table now, we may see a very weak Nina by the end of December. That has happened in the past with an ENSO cold-neutral in November (08-09). A cold-neutral at the very least is definitely assured. It’s going to be interesting to see what happens once the lag from this EWB catches up and the Nino like wave train blocking effects from the record WWB and AAM spike wear off

While the 1st half of December certainly looks chilly, no argument there, some of the bombastic claims on twitter right now that the pattern is locking in for winter are reckless to say the least. And I wonder if we start to see a more Niña like progression later on as the lag from this EWB catches up and the effects of the +AAM/WWB wave train wear off?

Let’s be honest, this winter will be judged on how much snow it produces. 99% of winter lovers base a winter being great or a fail on how much snow it produces. Even if this winter turns out to be -5F from Dec-Mar, if it ends up dry with below average snowfall, people will call it a huge fail and say the winter sucked. Great winters are remembered for snow not cold

The twitterologists have been hell bent on turning this into an I-95 snowstorm for Thanksgiving and Black Friday. Most rational people knew that was a lost cause

I hate to ask but do you think we see a continuation of the dry/drought pattern we had from mid-August to late November? Last week’s storm just being an anomaly in an overall feeding back dry cycle?

The risk with the upcoming cold wave is cold and dry. Unlike last year where we had the El Niño juiced STJ screaming along with a bunch of moisture and shortwaves….opposite this year and the strengthening -PMM supports a continuation of a weak STJ. We will be relying on vorts in the fast, progressive northern branch flow to “do something”. While that may work for New England maybe, south of there remains questionable, which is why the models aren’t showing a big coastal signal to go along with the cold in early December

That’s a good question….this is going to be a test to see what happens once this WWB/+AAM/Rossby wave flux wears off….does it just rebuild itself again or do we go back into the same old PAC pattern that we’ve had for years now?

The big issue is that we don’t have arctic air yet and the airmass that’s going to be in place is extremely marginal. While that may work later on in mid-late December/January/February, even early March, it’s not going to work near the coast in November unless there is very rapid deepening of the surface low off the coast and the midlevel lows take a good track to allow for strong UVVs/dynamic cooling and cold air drainage

Besides low snowcover and the warm lakes, Hudson Bay is still ice free. That is also going to modify the arctic airmasses

Multi model signal for a very strong SPV next month: