Winter 2018-19 Is Coming

[WxUSAF]

43 minutes ago, showmethesnow said:

 The great snow pack in Canada will provide a great source of cold to overcome climo in this case. 

 

I think the snowpack in Canada is already paying dividends with how cold the progs look for next weekend and beyond.  Probably will moderate with time, but widespread 20s looks likely with possible 10s for the colder spots if we get a good push of cA/cP air. 

 

As for the winter pattern, I don't think we're there yet, but we're moving in a generally forward direction.  I like seeing the cold air intrusion forecast with the pattern being decent, but not spectacular.  AO still looks neutral-ish over the next two weeks and it looks like the Kara Sea/Scandanavia ridge weakens some. 

[showmethesnow]

26 minutes ago, C.A.P.E. said:

I am optimistic overall. Not so much for any short term potential. I could see a winter storm happening for the highlands and up into NE over the next 2 weeks. My focus is towards early December, and how things evolve up top with the AO, and also if there are any hints of early NA blocking. I think we will probably have to be patient with the latter, but we really want a -AO to establish in December.

Over the years I have always tried to put a positive spin on things leading into winter highlighting the positives over the negatives even when it was quite obvious that we were heading into a dog of a winter. But not this year. Everything I have been seeing over the last month or two has been turning up aces for the potential for a blockbuster winter. Now with the possibility,  in my mind, of an early onset to winter added to what I believe will be a winter extended deep into spring my excitement levels are really peaking. Listened to DTs winter video yesterday and was glad to see that many of his thoughts mirrored mine so maybe I am not just being overly optimistic. 

[CAPE]

2 minutes ago, showmethesnow said:

Over the years I have always tried to put a positive spin on things leading into winter highlighting the positives over the negatives even when it was quite obvious that we were heading into a dog of a winter. But not this year. Everything I have been seeing over the last month or two has been turning up aces for the potential for a blockbuster winter. Now with the possibility,  in my mind, of an early onset to winter added to what I believe will be a winter extended deep into spring my excitement levels are really peaking. Listened to DTs winter video yesterday and was glad to see that many of his thoughts mirrored mine so maybe I am not just being overly optimistic. 

Lots of positive signs for sure. In my mind the AO is the key unknown at this point. With a weak/mod Nino and a more active STJ, the state of the AO/NAO is critical for persistent cold and more favorable southern/eastern storm track. If we end up with a neutral AO and minimal NA blocking, we depend mostly on the EPO/PNA combo, which can work, but we roll the dice more with storm track and timing the cold.

[nj2va]

2 minutes ago, C.A.P.E. said:

Lots of positive signs for sure. In my mind the AO is the key unknown at this point. With a weak/mod Nino and a more active STJ, the state of the AO/NAO is critical for persistent cold and more favorable southern/eastern storm track. If we end up with a neutral AO and minimal NA blocking, we depend mostly on the EPO/PNA combo, which can work, but we roll the dice more with storm track and timing the cold.

I didn’t hate the look at the end of the latest EPS weeklies if I’m reading them right.  Slightly higher heights in the AO domain and +PNA.  

[showmethesnow]

8 minutes ago, WxUSAF said:

As for the winter pattern, I don't think we're there yet, but we're moving in a generally forward direction.  I like seeing the cold air intrusion forecast with the pattern being decent, but not spectacular.  AO still looks neutral-ish over the next two weeks and it looks like the Kara Sea/Scandanavia ridge weakens some. 

When I look at 10+ days on the extendeds everything is Getting washed out. But within that look is definitely a fairly strong signal for where I believe we are going. We are seeing the higher heights, though muted, in the right places. If in the coming days we see those heights strengthen on the models I think we see other things fall into place including the AO. Right now though I think the models are struggling to decide whether to set the winter time pattern or go another round or two getting there. But we have seen the models rush pattern flips before so that could very well be the case here. The next few days will be interesting to see where the models decide to go with this.

[CAPE]

7 minutes ago, nj2va said:

I didn’t hate the look at the end of the latest EPS weeklies if I’m reading them right.  Slightly higher heights in the AO domain and +PNA.  

Agree. I commented on how great the PAC looked heading into mid Dec, but towards the end there are also indications the AO may be headed more negative. 

[poolz1]

Maybe the muted signal in the lr has to do with the MJO losing amplitude and heading for a weak phase 3 and into the COD. Will be interesting to see (if the MJO forecast is correct) what our default pattern will be when we head into the cod.

Again, if correct, it looks like we may get another tour of favorable phases as we head into December.

[showmethesnow]

1 hour ago, C.A.P.E. said:

Lots of positive signs for sure. In my mind the AO is the key unknown at this point. With a weak/mod Nino and a more active STJ, the state of the AO/NAO is critical for persistent cold and more favorable southern/eastern storm track. If we end up with a neutral AO and minimal NA blocking, we depend mostly on the EPO/PNA combo, which can work, but we roll the dice more with storm track and timing the cold.

Not so sure I am overly concerned with the AO. Think just about everything points to a predominantly negative state this winter so am fairly confident that is what in fact we see. But weather is going to weather so you know how that goes. Now the Nao is a different story. You know me, I am always hammering on having a -NAO. Though I would love to see it this winter I am not so sure it's the important player that we would expect in a typical winter. Looking where the heights have been favored so far actually favours a very good placement in NE Canada of the PV which can act as an effective substitute for the blocking the nao affords us. But we are still early in the game to see if that may in fact be the case.

[Bob Chill]

10 minutes ago, showmethesnow said:

Not so sure I am overly concerned with the AO. Think just about everything points to a predominantly negative state this winter so am fairly confident that is what in fact we see. But weather is going to weather so you know how that goes. Now the Nao is a different story. You know me, I am always hammering on having a -NAO. Though I would love to see it this winter I am not so sure it's the important player that we would expect in a typical winter. Looking where the heights have been favored so far actually favours a very good placement in NE Canada of the PV which can act as an effective substitute for the blocking the nao affords us. But we are still early in the game to see if that may in fact be the case.

02-03 was an interesting winter. Blocking during first half then entirely pac driven for second half. Not making any direct comparisons or anything. Just pointing out that we can still do fairly well during a nino with factors other than the ao/nao cooperating. 

After such a long predominant state of a +ao/nao, at some point it's going to reverse. No model does well beyond 2 weeks. We can infer strong states one way or the other continuing because they almost always do. I won't take any ao/nao forecast seriously until end of Nov. 

If I had to pick out one feature so far this fall that has my attention it would be the cold Canada/NA snowcover. The longer that continues the better off we are in the mid latitudes 

[psuhoffman]

1 hour ago, showmethesnow said:

Over the years I have always tried to put a positive spin on things leading into winter highlighting the positives over the negatives even when it was quite obvious that we were heading into a dog of a winter. But not this year. Everything I have been seeing over the last month or two has been turning up aces for the potential for a blockbuster winter. Now with the possibility,  in my mind, of an early onset to winter added to what I believe will be a winter extended deep into spring my excitement levels are really peaking. Listened to DTs winter video yesterday and was glad to see that many of his thoughts mirrored mine so maybe I am not just being overly optimistic. 

I agree things seem to be lining up for an early winter outbreak but we need to be prepared for a pullback and a lull period.  Every analog had one.  2014 started cold in November then warmed December into January.  2009 had a break after the December blizzard.  Even 2002 had a warm up after the early dec storm until xmas.  The analogs suggest a snowy winter but they don't support a wall to wall one so I just don't want to see people going full tilt when we inevitably get a warm up that lasts a couple weeks.  It's going to happen.  Hopefully we get some snow before any pull back like 2009 or 2002.  But history suggests even if we don't like 2014,2004,1986,1978 we still are probably going to do ok the second half.  

 

 

[psuhoffman]

56 minutes ago, poolz1 said:

Maybe the muted signal in the lr has to do with the MJO losing amplitude and heading for a weak phase 3 and into the COD. Will be interesting to see (if the MJO forecast is correct) what our default pattern will be when we head into the cod.

Again, if correct, it looks like we may get another tour of favorable phases as we head into December.

This chart is beautiful to my eyes. Seeing the mjo cycle the phases we want is a sign the modoki nino is having the desired effect on tropical forcing. Keep that going through winter and we will be good. 

[psuhoffman]

21 minutes ago, Bob Chill said:

02-03 was an interesting winter. Blocking during first half then entirely pac driven for second half. Not making any direct comparisons or anything. Just pointing out that we can still do fairly well during a nino with factors other than the ao/nao cooperating. 

After such a long predominant state of a +ao/nao, at some point it's going to reverse. No model does well beyond 2 weeks. We can infer strong states one way or the other continuing because they almost always do. I won't take any ao/nao forecast seriously until end of Nov. 

If I had to pick out one feature so far this fall that has my attention it would be the cold Canada/NA snowcover. The longer that continues the better off we are in the mid latitudes 

I'm in agreement. When I put together the list of similar enso years what stuck out most was how we seemed to get to a "win" several different ways. Even years without much help from the nao like 2015 and 2003 worked out.  The rare years that failed it seemed the Pacific failed to respond with a typical modoki nino pattern. But years it did worked out regardless of the nao. The one caveat being that if we want a HECS we probably need some blocking. I know PD2 but imo that was a fluke. We got lucky with a perfectly timed/placed arctic high and a wave that had an incredible moisture stream but wasn't too strong such to push too far north. And we still had a lot of mixing. But in general the years without blocking we got numerous snows but not blockbusters. I'm fine with that just pointing it out. 

[frd]

52 minutes ago, Bob Chill said:

02-03 was an interesting winter. Blocking during first half then entirely pac driven for second half. Not making any direct comparisons or anything. Just pointing out that we can still do fairly well during a nino with factors other than the ao/nao cooperating. 

After such a long predominant state of a +ao/nao, at some point it's going to reverse. No model does well beyond 2 weeks. We can infer strong states one way or the other continuing because they almost always do. I won't take any ao/nao forecast seriously until end of Nov. 

If I had to pick out one feature so far this fall that has my attention it would be the cold Canada/NA snowcover. The longer that continues the better off we are in the mid latitudes 

The longer it lasts, snow cover, the more likely it will continue to grow and expand.

Days still getting shorter, and then there is the feedback mechanism as well. 

Even if by chance the Western areas of North America lose any snow cover, all indications seem to indicate that snow cover and depth , both important, grow all month.  The NA SAI is very good indeed. 

[frd]

1 hour ago, psuhoffman said:

I agree things seem to be lining up for an early winter outbreak but we need to be prepared for a pullback and a lull period.  Every analog had one.  2014 started cold in November then warmed December into January.  2009 had a break after the December blizzard.  Even 2002 had a warm up after the early dec storm until xmas.  The analogs suggest a snowy winter but they don't support a wall to wall one so I just don't want to see people going full tilt when we inevitably get a warm up that lasts a couple weeks.  It's going to happen.  Hopefully we get some snow before any pull back like 2009 or 2002.  But history suggests even if we don't like 2014,2004,1986,1978 we still are probably going to do ok the second half.  

 

 

Yeah it looks like a deep cold outbreak coming up near later next week. This looks to be driven by the PV disruption forecasted a couple weeks ago.

The AO and the NAO both going negative again in the days ahead, for both this is the second dip into negative territory. Then later in the month there is one camp taking the AO positive and another camp taking it back down.  Surprisingly there is more consensus to keep the NAO closer to neutral or declining again. 

However there seems to be recovery on the PV after this minor disruption and at this point the pattarn later in the month ( after mid-month ) possibly seems to want to go more zonal. 

So, maybe we go to a back and forth pattern after the 17 th or 18 th.  The CFS , I know it is not good has some subtle support that the higher lattitudes might be changing down the road, to what would appear a warmer period corresponding with the zonal pattern on some models.  This is being supported somewhat at this time by the Euro.  

Not sure what this means for December yet. Of course many mets have a warner than normal,  or normal December temp-wise.

Of interest to mention for us here in the MidAtlantic is the NAO. HM had mentioned earlier this week that a wave 1 in November has a higher correlation to a December NAO.  

And a step further a wave 2 in November for whatever reason, has no correlation. 

 

[JakkelWx]

This October finished with an NAO value of +0.93, an AO value of +0.413, and a PNA value of +0.21. What you are seeing below is all the years that October featured a positive AO, NAO and PNA at the same time.

I think that December will be somewhat favorable for winter weather in the eastern U.S. Slight troughing in the Gulf of Alaska still exists and ridging along the west coast, however there are still lower heights than average in eastern U.S. and would provide decent chances if it came to fruition. But I think December this year will be the hardest month to forecast as there are a lot of conflicting signals regarding the setup of the atmosphere, for example blocking and SSW impacts, but December can go either way.

January looks to be a more moderate and ambiguous month, especially as we head into February with high-latitude blocking beginning to develop decently. The presence of this blocking allows for colder air to penetrate the E US even with lower than average heights along the west coast and Alaska.

Meanwhile, February looks to be the most favorable month for the eastern U.S. There is a strong blocking signal with prominent confluence over Nova Scotia, which would lock in cold air. Lower than average heights in the western U.S would allow for the STJ (Sub-Tropical Jet) to open up, which would lead to a high probability of overrunning events. Overall, this month looks to have the highest probability for a major storm. March also looks favorable with a strong cold air feed into the central united states with slight NAO blocking. Similar to December, the anomaly scale goes up to 35m, which means that the signals for any atmospheric feature are weak. Of all of the months throughout this coming winter, February has the strongest signal for cold air infiltration into the E US with anomalous NAO blocking like a lot of other mets are saying. It looks like there is probably not going to be any long periods of unfavorable patterns for winter weather.

What's different about this winter is that the past few years, December has been thrown out as a decent winter weather contender. This winter, NYC and the Mid-Atlantic sub-forum has a higher than usual chance to see a big winter this year, which I am rooting for, because the NAO has been positive for many years. 

I still like what i am seeing as far as now.

[Maestrobjwa]

8 hours ago, frd said:

Yeah it looks like a deep cold outbreak coming up near later next week. This looks to be driven by the PV disruption forecasted a couple weeks ago.

The AO and the NAO both going negative again in the days ahead, for both this is the second dip into negative territory. Then later in the month there is one camp taking the AO positive and another camp taking it back down.  Surprisingly there is more consensus to keep the NAO closer to neutral or declining again. 

However there seems to be recovery on the PV after this minor disruption and at this point the pattarn later in the month ( after mid-month ) possibly seems to want to go more zonal. 

So, maybe we go to a back and forth pattern after the 17 th or 18 th.  The CFS , I know it is not good has some subtle support that the higher lattitudes might be changing down the road, to what would appear a warmer period corresponding with the zonal pattern on some models.  This is being supported somewhat at this time by the Euro.  

Not sure what this means for December yet. Of course many mets have a warner than normal,  or normal December temp-wise.

Of interest to mention for us here in the MidAtlantic is the NAO. HM had mentioned earlier this week that a wave 1 in November has a higher correlation to a December NAO.  

And a step further a wave 2 in November for whatever reason, has no correlation. 

 

Now I didn't quite understand what he meant by Wave 1 and Wave 2...Could one of you elaborate on what that means for the NAO? (And what do we want to see from those waves that could indicate which direction the NAO might go next month?)

[frd]

21 minutes ago, Maestrobjwa said:

Now I didn't quite understand what he meant by Wave 1 and Wave 2...Could one of you elaborate on what that means for the NAO? (And what do we want to see from those waves that could indicate which direction the NAO might go next month?)

To explain HM really takes a PHD but basically he did a series ot tweets regarding wave 1 activity in November amd measured by amplitude ( how strong ) against the following month of December and the NAO . He also filitered his data further by looking at the MEI >0 and that brought him 20 results. I believe his last update a few days ago indicated the wave 1 was coming in 6 to 10 days so now thats 2 to 7 days and he stated it needs to keep coming and and be stronger.

I just read the post above about the positive NAO at + 1 or greater for 7months in a row. Ouch ! Not sure what it will take for a long duration -NAO phase this winter.   

[Maestrobjwa]

12 minutes ago, WxWatcher007 said:

Good lord. 

Ew yuck!!! Why...just why? Lol Man I hope we can get that to break soon!

[Bob Chill]

15 minutes ago, Maestrobjwa said:

Ew yuck!!! Why...just why? Lol Man I hope we can get that to break soon!

We're still a few years away from outdoing the late 80s/early 90's stretch. I'm thinking we should be good by winter of 2021-22. 

[mattie g]

I’m usually pretty down on our snow chances because I realize that we pretty much suck, but I’m getting the feeling that, come mid- to late-December, the atmosphere is going to be looking for excuses *not* to snow around here. We’ll hit a 2- or 3-week period when there’s no shot (maybe around the second week of January), but we’ll be tracking again before  almost before that period has started.

I could well eat my words, but I’m getting that funny feeling in the *very* bottom of my belly for this winter...

[Maestrobjwa]

3 minutes ago, Bob Chill said:

We're still a few years away from outdoing the late 80s/early 90's stretch. I'm thinking we should be good by winter of 2021-22. 

Ew yuck again...lol But does this mean that...we have lower odds of seeing a -NAO this winter, then?

 

[Maestrobjwa]

5 minutes ago, mattie g said:

I’m usually pretty down on our snow chances because I realize that we pretty much suck, but I’m getting the feeling that, come mid- to late-December, the atmosphere is going to be looking for excuses *not* to snow around here. We’ll hit a 2- or 3-week period when there’s no shot (maybe around the second week of January), but we’ll be tracking again before  almost before that period has started.

I could well eat my words, but I’m getting that funny feeling in the *very* bottom of my belly for this winter...

So what are you saying...ya think we'll be tracking with no results or that we may actually get something?

[mattie g]

9 hours ago, Maestrobjwa said:

So what are you saying...ya think we'll be tracking with no results or that we may actually get something?

I just feel like the atmosphere is getting primed to give us a lot of chances, and that we’ll need some incredibly bad luck not to pull off a really good winter. The pieces seem to be falling into place, and while we could certainly fail spectacularly, it’ll take some doing for that to happen.

We need to expect a break in the pattern at some point, resulting in a period when we’ll have no shot at wintry weather, but I also think that extended looks will have us tracking chances almost before that crap period even begins.

I could be completely wrong - and it certainly wouldn’t be the first time (and I also don’t have much skill beyond just going with feel and experience) - but this fall and all the long-range looks are getting me pretty excited for what’s to come.

[frd]

The SAI forecast for NA still impress me :

Looking forward today to the various updates form the Euro, like the 46 day EPS . 

 

[frd]

Maybe this sets the stage for a warmer period after November 18th . and then a warmer December possibly. 

On a positive note models did predict the displacment and that is a good sign. Still wondering about all wave 1 actvity , and if by early to mid December things change, or show signs of changing  with the NAO. 

Also, after the dislodge of super cold into the US later this week some say that gives the potential for extreme cold to grow over the pole in Siberia and that might be tapped into the next time there is a PV displacement or a cross polar flow develops in December or early Jan.  

 

[WxUSAF]

A zonal, more mild pattern is likely around thanksgiving week. Question is how long it lasts. MJO might move back into favorable phases around that time, which could shift a trough into the eastern CONUS by around 1 December.

[frd]

15 minutes ago, WxUSAF said:

A zonal, more mild pattern is likely around thanksgiving week. Question is how long it lasts. MJO might move back into favorable phases around that time, which could shift a trough into the eastern CONUS by around 1 December.

You agree that between December, Jan and Feb, and maybe even March that this December is the most challenging to forecast from a seasonal point of view? 

And if you agree, would you feel any better predicting December , if all the updated seasonal models this week went colder with December for some reason?

Thart is just speculation of course but just wondering. 

Maybe December  becomes a month of two seasons, possibly turning colder later in the month, however I have no comfort with that idea at all. 

[WxUSAF]

Nino climo argues for December to be the biggest wild card and has the most potential for warmth and lack of snow.  Seasonal models seem to back that up. If I had to make a wag, I’d think that we have some favorable periods in December.  Whether they pay off is impossible to know. 

[frd]

21 minutes ago, WxUSAF said:

Nino climo argues for December to be the biggest wild card and has the most potential for warmth and lack of snow.  Seasonal models seem to back that up. If I had to make a wag, I’d think that we have some favorable periods in December.  Whether they pay off is impossible to know. 

I agree too, but to say the entire 31 days is a washout is a bit unrealistic, no one can be that sure without a crystal ball. 

Besides, at this point making a call for a warm December can still backfire, because there is enough time let for a wintry period to suddenly appear during the month, not to mention the models have been experiencing difficulty with cold and warm periods. 

Certainly would not call for a December 2009 , ha ha , but the extreme nature of things does bring up the possibilty of cold and snow sometime in December, and if so, I request a White Christmas please. 

I am with you though, that at some point we may need multiple threads on various snow threats because it simply looks so active. If the pattern reaches it's full potential I might need to bring out the OLD saying from Herb Clarke, Katie Bar the Doors !!!  

[psuhoffman]

59 minutes ago, WxUSAF said:

A zonal, more mild pattern is likely around thanksgiving week. Question is how long it lasts. MJO might move back into favorable phases around that time, which could shift a trough into the eastern CONUS by around 1 December.

If we can get the mjo to keep cycling 8-2 with the same amplitude as the last two waves all winter were gonna like the results.