Carvers Gap

Again, the thing that is so very suspicious is that modeling locks this pattern in for 4-5 months in some cases. It could happen, but those looks are more than likely wrong. We have seen this over and over again during recent winters where modeling will show a pattern repeating for months on end. I tend to buy into 4-6 weeks weather cycles. If so, this current warm cycle should break sometime during late December (at the earliest) or by mid-January(latest). Now, that doesn't mean the new pattern is any better. I am just saying the repetitive pattern at 500 is suspicious. There are an increasing number of cold outliers in modeling even as we speak, but not worth really mentioning until those become trends. And if models are missing troughs amplifying in the East, that is probably something that will continue.

That ridge is going to want to hold in the East. La Nina is famous for that feature, but when it relaxes extreme cold surges eastward after building in the northern Rockies and Canadian prairies. It is interesting that Rockies have had so little snow right now. They love La Nina winters, and right now La Nina has not kicked in out there - but it is about to. The other interesting thing is that wx modeling seems to be missing troughs pushing eastward. I think they are handling phase 7 of the MJO poorly. Now, as we get closer to January, phase 7 switches from cold to warm in our region. Biggest takeaway from modeling right now is that wx models are getting the base pattern likely correct, BUT are missing trough amplifications. Those little troughs in the long range, are turning into much more formidable features as they draw closer. Now, if someone wants a true bummer for a Saturday, look what happened after the cold in '89. That is what we don't want.

@Mr. Kevin, Joe D'Aleo of WxBell published an article today about this analog year which was mentioned yesterday on this forum.

Man, I was loving it. I have been freezing my tail off in the morning. Bout the earliest I have ever had to dig out my running gloves. The lake at Bays Mountain near Feagins Gap had ice on the beaver ponds there. Not sure I have ever seen ice on that arm of the lake this early. Morristown released the November data....very cold and very dry. Chattanooga had the driest November during the last 80 years.

Yep. That followed an extended run of -NAO blocking. Both of those overwhelmed a really bad Pac set-up and a terrible MJO cycle with the exception of the 8-2-1 loop in December which worked well in E TN. -NAOs tend to run in cycles. Would be nice to get another this winter. Not feeling that, but who knows...maybe.

But it wouldn't be the first time at our latitude that we have gotten the shaft. LOL. We are used to it.

7 is not a warm phase during December though. It is cold to the Apps. Now, if it is stuck in January....it is a warm signal. It is part of the reason Decembers are often cold during La Nina's. The same Pacific set-up which makes December cold works against us during Jan/Feb. There are definitely cracks in modeling right now. No idea if that amounts to anything. But just imagine walking out on the ice, and the cracking noise becomes more frequent. That is what we are "listening" for. Right now, they are just random off runs. But make no mistake, modeling lost next weekend's amplification after originally having it. My guess is that we are going to have strong ridges this winter. I just don't see any way around that. However, I think the cold is going to push more than LR modeling depicts. We have seen that over and over again since early November. Hey, we manage a super cold shot last year with crap MJO phases. I will dig around this weekend and try to find some examples of MJOs that rotated 3-6 and still had snow. There is some correlation to North Carolina snowstorms and maybe phase 3? The North Carolina guys can correct me on that.

Haven’t looked at WXBell today. There are some similarities to 84-85, but to me that is a stand alone year. It is like a 100 year blizzard like ‘93. Not sure anyone can predict extremes like that with a ton of lead time. We will see more extreme cold and snow in our lifetimes. Harkening back to last year, the AMO has to flip for those winters of old to return regularly.

Plus, for whatever reasons, modeling has been missing amplifications for about the past 4-6 weeks. Not sure why.

I think there are some likely differences getting worked out in modeling. There should be cold pushing further East with an MJO phase 7. Ensembles are still pretty rock solid though. But if the models are going to crack, operationals will crack first.

The 12z GFS has a minor, northwest flow event for favored areas next weekend as well - meaning snow showers with minor accumulations on northwest facing slopes.

@jaxjagman, looks you called it with the cold shot next weekend. 12z GFS/GEFS has it and so does the Euro at 12z. I think this is a great example(if it verifies) of why modeling that looks wall-to-wall warm(or cold) is highly suspicious. Makes me wonder if there is a model input problem in terms of data.

The 12th-19th on the 12z GFS is now BN.

Yal'll we are going to have to get our act together if we are going to have a prolonged warm-up! 12z Euro with a true winter time air mass plunging into the East late in the run. HUGE grains of salt, but that is why I am skittish right now with modeling. Mercy, that is cold - some BN anomalies of 15-20 degrees.

12z CMC has winter weather centered on the 8th in areas on the northern and central Plateau, southeast Kentucky, and southwest Virginia. The Euro had a similar solution but was slightly north.

Jeff is the guru with angular momentum stuff. I admittedly look at not as often as I should. For me, some things in the LR don't quite add up. That said, there are some Nina's which were very warm winters. I highly doubt we go 12 weeks without some chances. Biggest concern right now is the dry pattern. I have generally found that winters with few chances often have very long periods where it doesn't have any precip. That means that an unfavorable temp pattern combined with drought makes it super difficult to sync cold air and infrequent precip. So, we need the frequency of precip to increase in addition to a more favorable temp pattern in the LR. It is really dry IMBY. That needs to change. As for where the pattern begins. I have always felt that because the weather pattern is a circle of sorts, it is hard to tell what causes what. SSTs are generally a great place. However, mountain torque is an under discussed driver(maybe the Urals?). Snow cover does matter. Sea ice numbers across the North Pole matter. I would suspect dust from the Sahara probably has some influence. And on and on.... But I generally agree that Eastern Asia and the Pacific are big drivers. Jax and Jeff look at those regions much more than I do, and know way more than me regarding those regions. Jax has a website that is pretty cool which correlates Bering Sea 500 heights with our regions. High latitude blocking is also important - reference to the SSW discussions. Just really looking for the driver each winter. I generally have found that when we are talking about the MJO in this forum, that the pattern has gone to crap! LOL. Right now, the MJO is the driver. That could change. My rule of thumb is the winter pattern begins to show itself around the third or fourth week of December. I do suspect the November pattern will repeat at some point. Get us some thunder in the mountains, and we know the change is coming. Going to enjoy running in some nice weather. Those November low temps were kicking my tail, man. LOL. It was cold in the morning here!!!!

Agree, Jax. Probably more likely severe than wintry but who knows. Just looking through model ensembles. The 12z EPS late in the run is trying to bring a ridge into the GOA(also found on the control run as well, especially the control run). Maybe a -EPO develops after that? 10th-20th looks pretty well set though as Jax mentions the 11-12th may hold some surprises in terms of the 500 pattern. Get a ridge in the GOA, and the western trough is either going to be very sharp or forced to kick eastward. So after the 20th, could be a continuation of a western trough or a ridge out West could develop for a time.

Crazy looking ice storm on the 12z CMC for the western half of the state around 144. Likely a one off, but impressive run nonetheless.

Very possible. Seems like that area may have had some snow that we didn't have in NE TN. We have family in Mo-town.

The 12z CMC is now showing a similar break(like the Euro yesterday) from continuity. The MJO is now almost universally in phase 7 in the medium to LR which is a cold signal west of the Apps (warm for January though). At 144 the CMC has a severe ice storm for western North Carolina. Interesting this is the timeframe which was showing up on modeling a few days ago and then went poof! Probably a one-off, but that CMC run is not warm. Details embedded within patterns are what matter. Beware when cracks start to show in modeling, especially with the MJO showing high amplitude into phase 7 on some modeling.

The cold snap of 17-18 isn't spoken about much as it produce very little snow and bitterly cold temps. It occurred at the end of December and went to mid-January. That was pretty much it for that winter if I remember correctly. Would not surprise me to see a similar event. If that cold spell had not straddled two months, it would have created a ridiculously cold anomaly for a month. That cold shot is hidden buried in monthly climatology by means which were warmer on the front and back end of that cold snap. That cold snap was preceded by very warm tempt, almost 15 degree departures during a few of the days prior. The rivers here in NE TN (which didn't have dams on them and warmer generator flows) froze almost solid. I remember seeing squirrels walking across creeks which were frozen solid but nearly clear ice due to lack of snow. The squirrel looked as curious as me when it walked out there. This reminds me a lot of that winter. If we had any precip at all, would have been more memorable than it was.

Good post. Will be interesting to see if the MJO sorts itself out during the next couple of days. WxBell has had some good articles about it - D'Aleo's, as I mentioned yesterday, discussion was stellar. The SSW potential is there, meaning sudden warming is modeled in the stratosphere. I think the warmth Dec 10-20th is legit. I think the anomalies will be warm enough to make December as they will override and BN days. After Christmas, all bets are off. Lots of conflicting signals out there. And yes, as we previously spoke in this thread, ridges that connect into high latitudes from low latitudes are often like bringing a jack hammer into a China shop regarding what happens after that. My guess would be that cold is going going to press into the western forum area after the 20th. Will go back and look at trends in a bit. CFSv2 is definitely interesting. Could just be a blip and/or the model just a wicked cold bias...Modeling the next few days will be interesting to watch.

To clarify.....that November turned out super cold!!! LOL. Models were locked on warm. Looked like a slam dunk, and bam! They reversed course. May very well have been a La Niña year. Happy first day of met winter, everyone!

As the phrase goes, time will tell.

Normally, I would toss the Euro. I remember years ago that I was trying to convince John that November was going to be warm. Every model had it, especially the Euro...until it cracked in one run. So, I have learned my lesson. I tend to question modeling which doesn’t show at least some variation. That November Euro would then waffle around for a few days, until it finally flipped. The CPC MJO data is trending to 7 with some 8 showing in the individual ensembles. D’Aleo had a great article today on the MJO. Basically said the BN SSTs in the 7, 8, and 1 regions (La Nina) are not allowing waves to propagate into colder regions. Said this is why models are sending the MJO into 7 and stalling or circling back to 6. So the big question is does it stall in phase 7 or loop back to 6? It may well be that we see some loops from 6-7 and back in a wash-rinse-repeat cycle. If so, the pattern will be more transient than models have depicted. I am super suspicious of the wall-to-wall warmer look. Runs against a big cluster of climatology. So, we will see if the Euro is a one-off. Should see it bounce around some of it is legit. It would take very little to move the needle towards cold. The -QBO is a surprise this winter and will have to be dealt with at some point. We usually get our share of winter here at some point.