December 2017 Long Range Disco

[showmethesnow]

46 minutes ago, NorthArlington101 said:

Take it for what it's worth...

 

 

DT hugs the Euro to distraction but for all that he is still a very good met.

[mitchnick]

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

Per the 12z EPS, looks like the core of the h5 -height anomalies, and the 850t anomalies, are moving eastward over the east coast towards day 15. So the trough should be well positioned for the week of the 11th.

So my call looks pretty good, eh Mitch?  

Hey, that's what makes my call so gutsy!  Lol

[Rtd208]

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

That is pretty close to the period I like. The 11th through the 15th.

Same here, I am going with the 10th-16th time frame.

[frd]

 

I enjoy Amy's input on the strat  

 

 

 

[frd]

Jason had a follow up regarding his thoughts targeting mid December.  

 

[showmethesnow]

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

That is pretty close to the period I like. The 11th through the 15th.

The biggest hesitation from getting somewhat excited about this upcoming period is from what we just saw occur the days around Thanksgiving. GEFS and EPS had great looks with the blocking initially only to slowly deteriorate it moving into the mid range and then we saw a rapid decline after that. Hopefully this will not become an issue with the models for this winter. 

[CAPE]

3 minutes ago, frd said:

Jason had a follow up regarding his thoughts targeting mid December.  

 

Guidance has been pretty persistent with perturbation of the PV, the attack coming from down low and up high. We will just have to wait and see to what degree this occurs. It is yet another indicator that is supportive of a favorable upcoming pattern.

[CAPE]

3 minutes ago, showmethesnow said:

The biggest hesitation from getting somewhat excited about this upcoming period is from what we just saw occur the days around Thanksgiving. GEFS and EPS had great looks with the blocking initially only to slowly deteriorate it moving into the mid range and then we saw a rapid decline after that. Hopefully this will not become an issue with the models for this winter. 

It is a bit of a concern. We have seen this play out many times over the past 5+ winters. However, given how locked in the 3 global ens have been for many runs, its hard to discount. I will say this- if it does not verify close to what is being advertised, I will be convinced that HL blocking has become a mirage- a fantasy- a myth, during the winter months, and I will never fall for it again, lol.

[poolz1]

I would argue that the blocking around TG did occur....The PNA was of no help and there was absolutely nothing to amplify the flow.  Also...3rd week in Nov and not near as much help from strat as the potential upcoming pattern.  I am just as wary, believe me.  This "feels" a bit different than past years...certainly doesnt guarantee snow...but I'll gladly roll the dice. 

[CAPE]

2 minutes ago, poolz1 said:

I would argue that the blocking around TG did occur....The PNA was of no help and there was absolutely nothing to amplify the flow.  Also...3rd week in Nov and not near as much help from strat as the potential upcoming pattern.  I am just as wary, believe me.  This "feels" a bit different than past years...certainly doesnt guarantee snow...but I'll gladly roll the dice. 

This.

[BTRWx's Thanks Giving]

3 hours ago, C.A.P.E. said:

You aren't reading it wrong, my friend. It is a little scary how good the advertised h5 pattern looks right now on all guidance. Key word is advertised. Lets hope the ground truth is close to what the models are teasing us with.

2009 la nina style #maybebanter

[showmethesnow]

22 minutes ago, poolz1 said:

I would argue that the blocking around TG did occur....The PNA was of no help and there was absolutely nothing to amplify the flow.  Also...3rd week in Nov and not near as much help from strat as the potential upcoming pattern.  I am just as wary, believe me.  This "feels" a bit different than past years...certainly doesnt guarantee snow...but I'll gladly roll the dice. 

The blocking did occur. But the big problem with it was how it verified compared to how it was initially represented. Initially we were seeing strong westerly based blocking that was extending quite a bit south. This in turn rotated the pv feature/trough being forced underneath farther south and west. And with the pv/blocking configuration we were seeing decent backing of the flow along with its corresponding amplification of the flow. What actually verified was weaker blocking that shifted east and poleward and we saw a corresponding shift of the pv/trough north and east. This different configuration of the pv/weaker blocking also did not allow the backing of the flow to the degree that we saw in the other case, thus less amplification. So in the first case, with the further south and westerly displaced pv and better amplification, we were seeing the NE CONUS being put into play. In the second case we were seeing everything shifted farther north and east with less amplification basically taking the Eastern US out of play.

[poolz1]

@showmethesnow  Thanks...Still learning here...I see what you are saying.  I guess my point for failure in that timeframe was more aimed at the time of year combined with no PNA help.  The block did occur as you said but orientation/location was the issue?  IF the PNA ridge would have popped would the outcome have been different?  I guess without PNA help then the block "below" would've had of been further south/west....?

 

 

[CAPE]

22 minutes ago, showmethesnow said:

The blocking did occur. But the big problem with it was how it verified compared to how it was initially represented. Initially we were seeing strong westerly based blocking that was extending quite a bit south. This in turn rotated the pv feature/trough being forced underneath farther south and west. And with the pv/blocking configuration we were seeing decent backing of the flow along with its corresponding amplification of the flow. What actually verified was weaker blocking that shifted east and poleward and we saw a corresponding shift of the pv/trough north and east. This different configuration of the pv/weaker blocking also did not allow the backing of the flow to the degree that we saw in the other case, thus less amplification. So in the first case, with the further south and westerly displaced pv and better amplification, we were seeing the NE CONUS being put into play. In the second case we were seeing everything shifted farther north and east with less amplification basically taking the Eastern US out of play.

Yes it did. And ultimately the block ended up further N/E and a bit weaker than advertised. The bigger issue was that the month was November, and expectations were generally too high given our climo.

[mitchnick]

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

Yes it did. And ultimately the block ended up further N/E and a bit weaker than advertised. The bigger issue was that the month was November, and expectations were generally too high given our climo.

Plus, the effects of blocking (that we're looking for) in November just ain't there short of a near historic blocking event. 

[CAPE]

1 minute ago, mitchnick said:

Plus, the effects of blocking (that we're looking for) in November just ain't there short of a near historic blocking event. 

Yup. Thats what I was getting at with the 'unrealistically high expectations' part of my post.

[showmethesnow]

 

41 minutes ago, poolz1 said:

@showmethesnow  Thanks...Still learning here...I see what you are saying.  I guess my point for failure in that timeframe was more aimed at the time of year combined with no PNA help.  The block did occur as you said but orientation/location was the issue?  IF the PNA ridge would have popped would the outcome have been different?  I guess without PNA help then the block "below" would've had of been further south/west....?

 

 

Strengthen and shift that blocking down as well as the lower height anomalies underneath it and you get a better representation of what initially was being advertised. This places the lower height anomalies and the corresponding trough, which was digging deeper, through the lakes region which is generally a good position for the east coast.

As far as the ridging in the West it is sort of like, 'which came first the chicken or the egg?'. Is the ridging in the west creating amplification of the trough downstream or is the trough and the backing of the flow causing amplification of the ridging upstream? I think in many cases it is a combination of both. But in this case I think the initial amplified trough was probably creating the better ridging to the west by backing the flow. Once you took out that amplified trough we saw a corresponding flattening of the ridge upstream of it as the flow was no longer being backed up. Just my take on it and I am sure others have their opinions.

[poolz1]

2 minutes ago, showmethesnow said:

 

Strengthen and shift that blocking down as well as the lower height anomalies underneath it and you get a better representation of what initially was being advertised. This places the lower height anomalies and the corresponding trough, which was digging deeper, through the lakes region which is generally a good position for the east coast.

As far as the ridging in the West it is sort of like, 'which came first the chicken or the egg?'. Is the ridging in the west creating amplification of the trough downstream or is the trough and the backing of the flow causing amplification of the ridging upstream? I think in many cases it is a combination of both. But in this case I think the initial amplified trough was probably creating the better ridging to the west by backing the flow. Once you took out that amplified trough we saw a corresponding flattening of the ridge upstream of it as the flow was no longer being backed up. Just my take on it and I am sure others have their opinions.

No...I completely see where your coming form and it makes sense.  "There are 360 ways to look at an elephant"  This is what makes this forum great...That and the panic room! lol 

[mitchnick]

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

Yup. Thats what I was getting at with the 'unrealistically high expectations' part of my post.

Oh, I know.  It's just that I used to work in the department of redundancy department and we used to like to say things more than once, if not twice or more.

[Bob Chill]

The NAO is inherently volatile and hard to predict. Verification scores are always low at longer leads. The AO is diferent. The steep drop did verify and it looks to be on the way down again. shortly after a very brief relax to neutral. This is an important clue and I feel more and more confident every day that we are headed for an anomalous neg AO Dec. If that is the case then our most imortant index for increased snow chances is breaking in our favor. 

[frd]

13 minutes ago, Bob Chill said:

The NAO is inherently volatile and hard to predict. Verification scores are always low at longer leads. The AO is diferent. The steep drop did verify and it looks to be on the way down again. shortly after a very brief relax to neutral. This is an important clue and I feel more and more confident every day that we are headed for an anomalous neg AO Dec. If that is the case then our most imortant index for increased snow chances is breaking in our favor. 

Bob any thought based off the 18 Z GFS and the Pac jet. I am hearing some say in another thread the Pac jet in the period days 11 to 16 might be a negative factor. Snowgoose mentioned this , a met in the NY forum. 

I feel its too early to worry about things at this point but I can see it might take a little longer for the potential of the pattern to really deliver results here in our neck of the woods.  I can relate to what Snowgoose had mentioned though , there was a winter not too long ago where Pac jet screwed everything up. It might have involved too many kickers causing storms not to slow down and take on that negative tilt. Also just to many vorts may have been the issue as well. I guess I am making excuses for failure even before the upcoming pattern takes hold. 

Would like to hear what you think. Thanks Bob  

[CAPE]

11 minutes ago, Bob Chill said:

The NAO is inherently volatile and hard to predict. Verification scores are always low at longer leads. The AO is diferent. The steep drop did verify and it looks to be on the way down again. shortly after a very brief relax to neutral. This is an important clue and I feel more and more confident every day that we are headed for an anomalous neg AO Dec. If that is the case then our most imortant index for increased snow chances is breaking in our favor. 

With the AO forecast to go significantly negative going forward, it gives me confidence that the forecast blocking in the NAO domain is real. They often go hand in hand. Just looked at the ens forecast for the AO/NAO/PNA from CPC. Its been a while since we have seen such a favorable forecast for that combo(trifecta!), plus the EPO is forecast to go negative.

[Bob Chill]

5 minutes ago, frd said:

Bob any thought based off the 18 Z GFS and the Pac jet. I am hearing some say in another thread the Pac jet in the period days 11 to 16 might be a negative factor. Snowgoose mentioned this , a met in the NY forum. 

I feel its too early to worry about things at this point but I can see it might take a little longer for the potential of the pattern to really deliver results here in our neck of the woods.  I can relate to what Snowgoose had mentioned though , there was a winter not too long ago where Pac jet screwed everything up. It might have involved too many kickers causing storms not to slow down and take on that negative tilt. Also just to many vorts may have been the issue as well. I guess I am making excuses for failure even before the upcoming pattern takes hold. 

Would like to hear what you think. Thanks Bob  

I didn't read the post but I'm never concerned about d11+ on an op run. I also keep it simple and don't worry about details like that way out in time. Right now all I care about is whether or not the ao/nao are going to behave as advertised in a week.

Honeslty, the only thing I'm worried about is cold and dry. Stout nao blocks and strong confluence under it can keep all the action south of us. It does look like energy is can undercut the pna ridge with ens mean h5 plots d11+. If we get too much of a good thing going in the high latitudes, that energy could easily get shunted south of us. We're still 10 days away from worrying about that though. 

[frd]

5 minutes ago, Bob Chill said:

I didn't read the post but I'm never concerned about d11+ on an op run. I also keep it simple and don't worry about details like that way out in time. Right now all I care about is whether or not the ao/nao are going to behave as advertised in a week.

Honeslty, the only thing I'm worried about is cold and dry. Stout nao blocks and strong confluence under it can keep all the action south of us. It does look like energy is can undercut the pna ridge with ens mean h5 plots d11+. If we get too much of a good thing going in the high latitudes, that energy could easily get shunted south of us. We're still 10 days away from worrying about that though. 

Thanks Bob. I am excited to see how things play out.  

[BristowWx]

6 minutes ago, Bob Chill said:

I didn't read the post but I'm never concerned about d11+ on an op run. I also keep it simple and don't worry about details like that way out in time. Right now all I care about is whether or not the ao/nao are going to behave as advertised in a week.

Honeslty, the only thing I'm worried about is cold and dry. Stout nao blocks and strong confluence under it can keep all the action south of us. It does look like energy is can undercut the pna ridge with ens mean h5 plots d11+. If we get too much of a good thing going in the high latitudes, that energy could easily get shunted south of us. We're still 10 days away from worrying about that though. 

That would be a classy problem.  Storms shunted south. I would prefer to be in that spot.  Especially since the north trend seems to be an ever present feature.  I fear total dryness with no storms at all.  I also fear the block breaking down before Xmas.  I fear clowns with hatchets and sad faces.  I have a lot of fears.

[Bob Chill]

3 minutes ago, BristowWx said:

That would be a classy problem.  Storms shunted south. I would prefer to be in that spot.  Especially since the north trend seems to be an ever present feature.  I fear total dryness with no storms at all.  I also fear the block breaking down before Xmas.  I fear clowns with hatchets and sad faces.  I have a lot of fears.

Well...our big ones usually happen during a rise of a neg nao so maybe it's all setting up just right for a Dec 09 redux later on. Or we score a 2-4/3-5 inside of 15 days and then get destroyed the week before Christmas. Both outcomes would be acceptable. 

[BristowWx]

6 minutes ago, Bob Chill said:

Well...our big ones usually happen during a rise of a neg nao so maybe it's all setting up just right for a Dec 09 redux later on. Or we score a 2-4/3-5 inside of 15 days and then get destroyed the week before Christmas. Both outcomes would be acceptable. 

Interesting about 09...awesome storm by every measure.  Yet it was almost gone by Xmas.  I remember the warmed up and rained.  It was still white but almost not...life in the MA.  We suffer for our snow.

[Bob Chill]

41 minutes ago, BristowWx said:

Interesting about 09...awesome storm by every measure.  Yet it was almost gone by Xmas.  I remember the warmed up and rained.  It was still white but almost not...life in the MA.  We suffer for our snow.

Many of our big storms come at the end of a favorable period. Jan 96, Dec 09, Feb 2010, and Jan 16 were all followed by a warmup/melt off. I think PD1 was similar but i cant remember clearly. I know i was off school for a week. PD2 was money. It kept on coming into March. The flip from a neg to pos NAO is great for big storms but sucks for retention. 

[DC2Winston]

Moved from DC to Winston-Salem NC over the summer. Used to complain that MA forum was too big geographically and crazy IMBY variance. But learned it was well worth it for the high-level talks and education. 

Now my forum spans like 25% of the CONUS. Ha!

Would love to see geographic sub-forums for winter events, in addition to storm specific. 

Dear Santa...

[BTRWx's Thanks Giving]

1 hour ago, Bob Chill said:

Many of our big storms come at the end of a favorable period. Jan 96, Dec 09, Feb 2010, and Jan 16 were all followed by a warmup/melt off. I think PD1 was similar but i cant remember clearly. I know i was off school for a week. PD2 was money. It kept on coming into March. The flip from a neg to pos NAO is great for big storms but sucks for retention. 

They're also preceded by that!