A change to a wintry pattern emerging after November?

[Carvers Gap]

There is very little operational model support today for any kind of susained Arctic outbreak in the Southeast. If anything, it is the exact opposite. Again, it does appear the lion's share of the cold is going West on the lee side of the northern Rockies. The Pacific is causing a problem downstream. Didn't we have a similar set-up in '02 where the Pacific fouled an otherwise great pattern(can't remember the exact year but that seems close)? This could be just waffling on the models. But something besides the NAO and AO is driving this pattern, otherwise it would be cold and stormy in the long range. Eventually, you would think those two would overwhelm the pattern. Two years ago, Nina should have overwhelmed the pattern like last year...but it did the opposite.

[lugnuts]

As horrendous as last year was if the weather gods can give me a splitting vortex with -nao and -ao throughout much of winter i will be very happy..How happy you say...As happy as a witch in a broom factory..lol...Last winter is gone and that in and of itself is enough to be optimistic about...

[griteater]

For some strange reason, that part of Allan's site is not loading. Can you either post a pic or a link?

[Wow]

+PNA & -NAO come 12/5? That would be our opportunity for any kind of arctic cold to make its way here. Neg. EPO also forecast for this period (higher heights over AK) to bring in the good stuff. Early/mid December still looking good.

[pcbjr]

Thanks!

Can access Allan now.

[nchighcountrywx]

I agree the Pacific is the problem right now and the Pacific can destroy a promising -NAO.

Other than a glancing shot of cold Saturday/Sunday, things don't look too good until at least December 05.

Already this is starting to have implications for our NC High Country ski slopes that need sustained temps down in the 20s to support rapid man made snow making to get a solid base going for December visitors.

[packbacker]

Wells maybe this is the year to get a crippling ice storm with a strong -NAO/-AO and crappy Pacific ala Dec 2002.

[Wow]

18Z gfs sets up a western trough and keeps it there the entire run

[pcbjr]

Yup.

It is, though, 18z GFS - which has issues.

More disturbing is the 12z Euro - which is basically showing a rather warm September-like set up for all of us down in Dixie.

[bhamwx205]

The pacific is killing everything. Until that stupid vortex over asia moves things dont look good in the lr. even if the ao and nao do go negative the pacific will rule the pattern

[Wow]

I'd still be wary of all models as they have been quite divergent from run to run beyond 7 days. The pacific will keep any cold from locking in for at least the next week, but beyond that, some model runs have been bringing on a +PNA so I wouldn't get too worked up on the models in the mid to long range.. even the Euro. They have all been highly variable.

[WidreMann]

How's that pattern change coming? Oh, what's that? The Euro was right after all? Huh. Funny that.

[Wow]

How's that pattern change coming? Oh, what's that? The Euro was right after all? Huh. Funny that.

You don't believe in pattern change? There's scientific consensus!!!

[SoCoWx]

How's that pattern change coming? Oh, what's that? The Euro was right after all? Huh. Funny that.

This guy.

Because what would winter be without Widremann's smart*** remarks?

[griteater]

DT write-up on wxrisk hits on a lot of what we've been covering in here...

"Also here in case you missed it is the latest upper air forecast for week three and week four from NOV 22 CFS. What is significant here is that it continues to show that the first half of December is NOT going to feature Below Normal temperatures and it does NOT look very stormy for most of the country. I said this back in my initial winter forecast and I don’t see any reason to change it.

However by week 3 DEC 6-12 we see a very strong blocking feature over North Central Canada which really counts as a extremely slow large -NAO. The week 3 pattern is actually one of those rare instances where even though the NAO is large and strong, temperatures do not show a cold pattern. The problem is that we continue to see that trough over Alaska. That feature which in the weather business is called a positive phase of the EPO (+EPO) is forcing a trough over the far eastern Pacific and along the West Coast of North America….. or a -PNA pattern. As a result the cause of the -NAO block over North Central Canada is so large… the interaction between this feature and the -PNA means that there’s no cold air flow coming into the U.S. As result temperatures dec 6-12 will be pretty mild for most of the country east the Rockies.

However by week 4… the +EPO is gone… and replacing it is a -EPO feature… which means a strong West Coast Ridge extending all the way up into Northwest Canada. The expansion of this RIDGE over Northwest Canada means that the-NAO has to be pushed to the east a little so it moves into the more classic position over North America— between Labrador and Greenland. This setup +PNA and -NAO and a -AO is very favorable for significant East Coast or eastern U.S. winter storm to develop in mid December."

[WidreMann]

You don't believe in pattern change?

Neither do the models.

There's scientific consensus!!!

Indeed.

[WhiteoutWX]

I think people should take a step back from the ledge here. The fact is we have a stratospheric warming/vortex split going on which signals an increase in blocking over the next few weeks. Regardless of what the 300 Hr GFS shows right now this pattern may still produce over the next few weeks.

It's only late November..

[valkhorn]

How's that pattern change coming? Oh, what's that? The Euro was right after all? Huh. Funny that.

Our weather here has changed a bit from last week. The pattern will change for many parts of the country. Just because things don't change for you, don't get all whiney at us. Maybe to spite you I'll go and see some mid 20s tomorrow at or over 5500 feet. They also likely had snow showers up there tonight.

Our high tomorrow will be about 41F. That's a big change, and well below average for this time of year. In fact, it'll likely e our coldest high of the season.

[valkhorn]

I think people should take a step back from the ledge here. The fact is we have a stratospheric warming/vortex split going on which signals an increase in blocking over the next few weeks. Regardless of what the 300 Hr GFS shows right now this pattern may still produce over the next few weeks.

It's only late November..

Sorry for double posting but multi quote fails on my iPad. I think the problem is that the patterns will change, but because it won't bring exactly the snowstorms everybody dreams about people complain. It's not even December yet. You can't really control the weather, so why be a jerk about it to everyone else? Not you specifically, of course, but some people go overboard. A little war,th in the forecast and it's a historic hear wave. A snowstorm at 384 hours and it's a new ice age. The same happens with hurricanes, too. Have some patience, and ignore those who have nothing to offer but emptiness and pessimism. Youll live longer, and you'll be happier.

[WidreMann]

I was waiting for valkhorn to show up. Like clockwork, he did. Does he have a bot that scans for posts by me so that he can come in and construct and demolish strawmen about me?

[MADDOGG]

I was waiting for valkhorn to show up. Like clockwork, he did. Does he have a bot that scans for posts by me so that he can come in and construct and demolish strawmen about me?

You do a great job of it yourself.

[Poimen]

well, the good news this morning is the LR 0Z GFS replaces the E Pac trough with a ridge beyond day 10. We are going to need that to happen, irrespective of the NAO/AO, if we are going to see any wintry pattern in these parts, in my opinion. Hope it sticks.

[Isopycnic]

Our weather here has changed a bit from last week. The pattern will change for many parts of the country. Just because things don't change for you, don't get all whiney at us. Maybe to spite you I'll go and see some mid 20s tomorrow at or over 5500 feet. They also likely had snow showers up there tonight.

Our high tomorrow will be about 41F. That's a big change, and well below average for this time of year. In fact, it'll likely e our coldest high of the season.

This is typical for this time of year. Our first cold wave comes in around Thanksgiving day,,, kind of like our first real chance of snow or flurries happens Dec 5th.

[Isopycnic]

You do a great job of it yourself.

Widremann is the anti JB. Being a pessimist makes him right a lot of the time.

[Isopycnic]

Widremann is the anti JB. Being a pessimist makes him right a lot of the time.

Wirdermann is one of the only "snow weenies" that I know that of that will actually lower his snow total reports just to say he was generally screwed.

[Wow]

Widremann is correct that the models are not indicating a pattern change for the colder, at least in the next week. -PNA really battling against the favorable Atlantic setup. They are predicting a breakdown of the +EPO/-PNA after the first week of December. We'll see if it holds.

[Lookout]

Wirdermann is one of the only "snow weenies" that I know that of that will actually lower his snow total reports just to say he was generally screwed.

That's a new one isn't it?

I won't lie, he cracks me up big time when he gets screwed. Its not because I want him to get screwed but he's just got this way of making me laugh like hell when he does.

Widremann is the anti JB. Being a pessimist makes him right a lot of the time.

Totally true. People might not like hearing it but he's more right than wrong.

[GaWx]

Assuming about the same magnitude, I look at the -PDO and -NAO/-AO as rough offsets of each other and pretty much an ongoing battle won by each side at different times for the SE US. (This isn't NE, where similar magnitudes for each favor good winters.) So, if I were to assume similar negative magnitudes for each, I'd go with a fairly average winter with periods of cold interspersed with about equal periods of mild. I'm just generalizing here. If one views the maps showing the correlations, he/she would see that the correlations of -PDO and +NAO/+AO to warmth are roughly at the same level for the SE US. The key will be to see how they evolve. If the PDO remains negative but at least rises to only mildly negative..say ~-0.50...and the -NAO/-AO remain in their sometimes impressively neg. states, cold should win. Also, the neutral positive ENSO shouldn't hurt and may even help some. Unfortunately, we haven't gotten the weak Nino I was hoping would return. Weak Ninos along with -NAO/-AO are very conducive to a predominant +PNA. I'm hoping that we get some +PNA correlation with a hopefuly high end neutral positive (as opposed to low end).

Right now, I'd give the Pacific a C- (I'd have gone no better than a D had we had a solid Nina). The Atlantic gets about an A-. In combo, I'd give it a B- right now. If the PDO falls back to strong negative and we maintain the -NAO/-AO, I'd then give the ATL/PAC about a C or this winter. OTOH, if the PDO were to somehow rise to moderately + (very unlikely with no Nino), I'd go as high as A- oceanwise and we'd even be looking at another 1935-6 as the best case. So, there's still a lot to be determined, largely due to the PDO.

[Cold Rain]

That's a new one isn't it?

I won't lie, he cracks me up big time when he gets screwed. Its not because I want him to get screwed but he's just got this way of making me laugh like hell when he does.

Totally true. People might not like hearing it but he's more right than wrong.

All you have to do in the SE is wake up every day and say "it's not going to snow today" and you'll be right 99% of the time.

You can really only look at potential patterns or individual threats in two ways: Either try to find ways it can all come together, or try to find ways it can all fall apart. Most of the time, it doesn't all come together, so if you constantly take the approach of pessimism (assuming you want cold and snow), you'll generally be right.

On the other hand, it's fun to speculate and watch for clues/signals that a more favorable Winter situation is on the horizon. Even knowing it may not work out or work out immediately, it's still fun to discuss the potential. I think that's how most weather enthusiasts operate.

Either way, it's only November 24, and it actually feels like Fall (or today, even Winter), so at this point I'm not sure if there's really anything concrete to be overly delighted or worried about. Just enjoy the Fall and enjoy watching the pieces fall into place.

[valkhorn]

That's a new one isn't it?

I won't lie, he cracks me up big time when he gets screwed. Its not because I want him to get screwed but he's just got this way of making me laugh like hell when he does.

Totally true. People might not like hearing it but he's more right than whrong.

Well his predictions are vague and non specific enough that you can pull anything out of it. It's fine if you pull out some evidence and give a forecast either way, but you don't have to be a jerk about it. He always shows up when he gets screwed and takes it out on others, but when the mountains here were getting three feet of snow last month he was mysteriously absent. My signature says all you need to know about him.

By the way, at least for us the pattern changed slightly. The forecast next week is greatly different than last week here. Winter hasn't started yet, anyway.