January Medium/Long Range Discussion

[poolz1]

6 hours ago, cbmclean said:

Been reading several items about wanting a Pacific jet extension to help shake up the NPac ridge.  I was thinking wasn't it last year that we were desperately hoping for the jet to retract so we could shake off the Pac puke?  So an extended jet is sometimes good and sometimes bad?  Anyone with more knowledge have any insight?

Great point....I have been thinking the exact same thing.  I see CAPE's point above but still don't quite get it tbh.  Maybe a case of like everything else in life...moderation is best.  As I sip on my third bourbon! lol

 

 

[CAPE]

5 hours ago, WinterWxLuvr said:

My expert analysis says that whatever we have, we want something else. 

The the last couple runs of the EPS in the LR is for you. +AO/NAO, and a neutral PNA.

[CAPE]

1 minute ago, poolz1 said:

Great point....I have been thinking the exact same thing.  I see CAPE's point above but still don't quite get it tbh.  Maybe a case of like everything else in life...moderation is best.  As I sip on my third bourbon! lol

 

 

It's Complicated.

Firstly a -PNA isn't always a bad thing.

Jet extensions occur more in Nino, while retractions are favored in a Nina. A poleward shift is more likely in a Nina. MJO phase can have an impact, however. Don't quote me, but I think jet extensions in general are favored during MJO phases 7 and 8, so if we are in fact seeing an extension of the Pac jet (during a Nina) it is probably related to the MJO. What a surprise!

I am sipping on my first bourbon after a couple glasses of wine with dinner.

[poolz1]

17 minutes ago, CAPE said:

It's Complicated.

Firstly a -PNA isn't always a bad thing.

Jet extensions occur more in Nino, while retractions are favored in a Nina. A poleward shift is more likely in a Nina. MJO phase can have an impact, however. Don't quote me, but I think jet extensions in general are favored during MJO phases 7 and 8, so if we are in fact seeing an extension of the Pac jet (during a Nina) it is probably related to the MJO. What a surprise!

I am sipping on my first bourbon after a couple glasses of wine with dinner.

Appreciate it. As cbmclean said, I recall praying for the PAC jet to chill out last winter.  But, our MJO phases were completely different, iirc? The never-ending hobby....always more to learn.

Cheers!

[CAPE]

29 minutes ago, poolz1 said:

Appreciate it. As cbmclean said, I recall praying for the PAC jet to chill out last winter.  But, our MJO phases were completely different, iirc? The never-ending hobby....always more to learn.

Cheers!

My understanding is an extended jet places the exit region further east, which favors a ridge over the western US. This is more common during a Nino, while jet retraction places an anomalous ridge further west over the N Pac, and is associated with a Nina (Chuck's beloved -PNA!) Simple explanation.

Cheers!

[Maestrobjwa]

Hey yo!! THE Uccellini cited the WDI (we're due index)...I feel validated, lol It is herby canon! 

 

[IronTy]

34 minutes ago, Maestrobjwa said:

Hey yo!! THE Uccellini cited the WDI...I feel validated, lol It is herby canon! 

 

That's basically how my retirement has gone so far.  Minus the final interview and budget woes and whatever.  

[nj2va]

GFS gets next weekend’s potential storm down to the 940s over Maine, which is pretty impressive IMO.  At least something to track and could set up the mountains for their first warning event of the winter.

[clskinsfan]

11 minutes ago, nj2va said:

GFS gets next weekend’s potential storm down to the 940s over Maine, which is pretty impressive IMO.  At least something to track and could set up the mountains for their first warning event of the winter.

Yeah. That thing is a monster. Would probably see a wind driven squall at least. 

[nj2va]

5 minutes ago, clskinsfan said:

Yeah. That thing is a monster. Would probably see a wind driven squall at least. 

Yep, regardless of the rain to snow output on the models (which we don’t do well here), could see the squally snow showers in that setup.  

960s in the Gulf of Maine on the CMC on the 00z, btw.

Who’s staying up for the Euro? 

[Amped]

11 hours ago, Amped said:

Add this to the list of my favorite model glitches.  CMC 180-192 shows a 39mb pressure drop on an ET cyclone over land.   That's almost double the Cleveland superbomb.

00Z GFS shows it too now, 38mb in 12hrs this time. It would be close to a 12hr deepening record for an ET cyclone if somehow it verified.

[Weather Will]

WB 6Z GFS early next week storm.

[CAPE]

Looking through the GEFS members, about half imply a more amplified storm that would probably track a bit too far N/W for much of our area(for frozen) but there are others that are less amped/flatter and colder, and there are a few that imply a second wave tracking further south on the 3rd. 

[CAPE]

The Euro ens tracks the New Years storm well NW, then has a trailing wave along the advancing cold front Jan 2-3 timeframe. Verbatim it would be cold chasing rain but still a week out so plenty of uncertainty, and we just cant know- although most of us probably have an intuitive feel for how it might play out. 

[aldie 22]

2 minutes ago, CAPE said:

The Euro ens tracks the New Years storm well NW, then has a trailing wave along the advancing cold front Jan 2-3 timeframe. Verbatim it would be cold chasing rain but still a week out so plenty of uncertainty, and we just cant know- although most of us have probably have an intuitive feel for how it might play out. 

I just hope that those who have the intuitive feel tell us at minimum 3 times a day about that intuition 

[CAPE]

In the long range all 3 global means have a very serviceable Pacific look with the mean trough and cold directed more into the central US- and with the advertised look it would also be colder in the east. The differences are up top/on the Atlantic side. GEFS maintains a -NAO, EPS looks neutral to somewhat positive, and the CMC ens is somewhat in between, but has a colder look for the east overall. Maybe we lose the blocking for a time, but it has not done much good with the raging NPAC ridge. With improvements there, we should see more cold chances via a neutral PNA/ -EPO.

eta- one other thing of note is the PV looks somewhat perturbed/elongated in the LR, and the indication of southward displaced TPV lobes can be seen on the mean. Not a bad look for getting cold air excursions further south.

[CAPE]

8 minutes ago, leesburg 04 said:

I just hope that those who have the intuitive feel tell us at minimum 3 times a day about that intuition 

Oh its coming.

[ldub23]

By the time  01march comes we will be sick of snow and  cold!!

[StormchaserChuck!]

0z GFS ensemble mean had +400dm -PNA, 6z has -EPO. It will be -EPO with Low underneath +PNA. We'll be cold as long as the NAO stays negative

[CAPE]

16 minutes ago, StormchaserChuck! said:

0z GFS ensemble mean had +400dm -PNA, 6z has -EPO. It will be -EPO with Low underneath +PNA. We'll be cold as long as the NAO stays negative

Chuck!

+PNA

[Baltimorewx]

The trailing wave idea on the GFS on the 2nd-3rd is interesting and I suppose could work but it also may not (haha enlightening news I know)

[BristowWx]

3 minutes ago, Baltimorewx said:

The trailing wave idea on the GFS on the 2nd-3rd is interesting and I suppose could work but it also may not (haha enlightening news I know)

there just isn't much cold behind it on this run.  the deep trough is shallowing over time..if that is even a word

[aldie 22]

1 minute ago, BristowWx said:

there just isn't much cold behind it on this run.  the deep trough is shallowing over time..if that is even a word

Intuitive 

[Ralph Wiggum]

10 minutes ago, Baltimorewx said:

The trailing wave idea on the GFS on the 2nd-3rd is interesting and I suppose could work but it also may not (haha enlightening news I know)

12z looks more Nina.. trailing wave getting shredded in the fast flow. Probably makes the most sense at this point with less of a transient PNA ridge popping now and more of a central USA full ridge developing and linking with HL ridging.

[CAPE]

13 minutes ago, Ralph Wiggum said:

12z looks more Nina.. trailing wave getting shredded in the fast flow. Probably makes the most sense at this point with less of a transient PNA ridge popping now and more of a central USA full ridge developing and linking with HL ridging.

This upcoming period has consistently looked to feature a transient eastern trough with a ridge building right behind it on the means as the trough(temporarily) re-digs out west. The window is brief and pretty much centered on a wave forming along the boundary. Too soon to know if it will be weak, shredded, too warm,(insert other failure mode), etc, but the idea is still there on today's 12z GEFS.

[Ji]

2 minutes ago, CAPE said:

This upcoming period has consistently looked to feature a transient eastern trough with a ridge building right behind it on the means as the trough(temporarily) re-digs out west. The window is brief and pretty much centered on a wave forming along the boundary. Too soon to know if it will be weak, shredded, too warm,(insert other failure mode), etc, but the idea is still there on today's 12z GEFS.

this is a little terrifyinglooks like a severe -EPO but still warm in the east. 

[Weather Will]

Early next week storm looks like the Washington football team on 12Z GEFS.

[CAPE]

1 minute ago, Ji said:

this is a little terrifyinglooks like a severe -EPO but still warm in the east. 

-PNA!!

I start looking at op runs when we have an identifiable threat inside 7 days. Why look at advertised longwave pattern stuff on an op 10+ days out when it dramatically changes run to run. Looks less scary on the GEFS.

[psuhoffman]

9 minutes ago, Ji said:

this is a little terrifyinglooks like a severe -EPO but still warm in the east. 

The TNH loading pattern has been killing us for a while. The fact that the gulf is on fire doesn’t help either. But I’ve  also noticed it’s been harder than it should be to suppress the SE ridge from going ape the last 5 years.  And I’m not talking about when the EPO is mediocre and the PNA is -4. But even when it seems like it should be a workable look the SE ridge goes nuts. 

[CAPE]

6 minutes ago, psuhoffman said:

The TNH loading pattern has been killing us for a while. The fact that the gulf is on fire doesn’t help either. But I’ve  also noticed it’s been harder than it should be to suppress the SE ridge from going ape the last 5 years.  And I’m not talking about when the EPO is mediocre and the PNA is -4. But even when it seems like it should be a workable look the SE ridge goes nuts. 

A fixture in the +TNH is an EPAC ridge, same as a Nina. Flattening the SE ridge with the current background state likely requires favorable shifts in the configuration of the NPJ, and MJO (and continued help from the NAO).  Seeing a much more serviceable Pac advertised on the means in the LR but no idea if it's real yet.