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January 2019 Medium/Long Range Pattern Discussion


John1122
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Hopefully!

Day 10 on Euro definitely has a nice look that the PNA/ EPO could amplify further with that upper low scooting back toward Russia across the Bering strait. If this progression continues, I predict tomorrows weeklies look about the same, but next Monday's look amazing. 

EDIT, not that they looked real bad before, but I bet they look even better when it all initializes a better look

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2 minutes ago, Holston_River_Rambler said:

Hopefully!

Day 10 on Euro definitely has a nice look that the PNA/ EPO could amplify further with that upper low scooting back toward Russia across the Bering strait. If this progression continues, I predict tomorrows weeklies look about the same, but next Monday's look amazing. 

Check out the trough over Alaska on the Euro.  Really makes a dash to get into the Aleutians from 192-240.  Once it makes that trek and pops more ridging in the EPO region it's game on in the not too distant future for someone downstream.  This sure looks like it was a big step toward the GEFS and GEPS.  We will know soon enough.

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The 12z GEPS looks good.  The GEFS may be less enthused, but is increasingly cold over Canada for d10-15.  I am always somewhat cautious of the operationals leading the way w/ LR modeling, but it does happen sometimes.   If the models keep flipping around that usually tells me a couple of things during winter.  First, there is potential for really cold air to enter NA.  Second, the current pattern is subsequently about to flip.   The other thing...these are operationals that are picking things up around d10.  One might argue that the change to a colder pattern is moving forward in time.  I suspect the flip-flopping will continue.  Again,  I like the idea of a pattern lasting 4-6 weeks during winter.  If one takes the current pattern...it is about due to switch.

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5 minutes ago, Holston_River_Rambler said:

Yeah agreed. That's what I was trying to say though may have come out wrong. 

Now what I'm wondering, is it really just as simple as getting a Euro that initializes Pac convection outside of MJO phase 5? 

Looks that way today. 

It was, I just failed to process your post fully before posting my own thoughts.........  At least I know someone was thinking like me.  Not sure that's a good thing though.  lol

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The SOI has been negative for three days...pretty interesting to see the model trends today with that in consideration.  Also, we have the strat split process which may be ongoing for the next couple of weeks.  I think Amy Butler on Twitter mentioned that it would be considered one event if the winds stay reversed.  If things were going to begin change in LR modeling....this would be an understandable window.  Some unknown variables begin to be known.  For each those that gets defined better... the better the modeling will be.  Good trends today.  Let's see if they hold.

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Here's a thought about the EPS days 9-15. May be completely wrong and grasping for straws, but thought it was interesting that despite how bad the H5 anomalies look at least the PAC jet retracts in that time frame and some of the stream lines are arching up over AK. 

 

giphy.gif 

Looking at Euro MJO ensemble RMM plots, most show CODish for days 9-10, so if that signal is rather cloudy and that is what drives the PAC jet, maybe there are a wide range of options in all 51 members that wash out the overall H5 pattern after days 10? I guess the same could be said for any ensemble suite though. 

Long story short, maybe we have a couple of good signals showing on the EPS, despite how bad the H5 the anomalies look. 

To play devil's advocate against my own argument, it's possible I've just made a slightly more picture filled version of the old "EPS only adjusts slowly" argument. And my whole argument of "washout" could also be used against what I'm saying. 

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SOI down to -13.00 and that is about all that looks good this AM.

For those interested in this sort of thing, Masiello laid down the law on the tropical convection last night. Nice specific analysis of how it's all connected to our current pattern. The whole series was interesting, but I'll use this one as an explanation for the BOMM RMM plot I posted yesterday above:

 I think "ER" here means Equatorial Rossby Waves.

He doesn't mention it, but wonder how the coronal hole thingy plays into all this too. 

Sometimes when reading Masiello, I'm reminded of an exchange from Fellowship of the Ring: 

Frodo: "And it is also said, 'Go not to the elves for counsel, for they will say both no and yes.'"

Gildor: "Elves seldom give unguarded advice, for advice is a dangerous gift, even from the wise to the wise, and all courses may run ill." 

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Just a very warm look on most modeling this AM for at least the next two weeks.  I continue to believe we will see a backloaded winter, but there is virtually no model support for that idea this morning.  Time will tell.  Still going to roll with climatology.  The falling SOI is a good sign.  The “one step forward, two steps back” for the past week is not a good sign.  

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11 minutes ago, Carvers Gap said:

Just a very warm look on most modeling this AM for at least the next two weeks.  I continue to believe we will see a backloaded winter, but there is virtually no model support for that idea this morning.  Time will tell.  Still going to roll with climatology.  The falling SOI is a good sign.  The “one step forward, two steps back” for the past week is not a good sign.  

Keep waiting but in two to three weeks, if there is still no indication of at least freezing temps, I say pack it in. My opinion of course, just haven't liked the writing on the wall for the last four weeks lol.

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If you had told me we’d be at the end of December facing a very strong SSW, with a split/wind reversal, more forecasts for a continued disturbed strat, a weak El Niño, and a crashing SOI heading into 2019 and we’d be talking about a pattern that isn’t changing on modeling I would have called you crazy.  I’m starting to REALLY dislike poorly placed tropical convection 

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1 hour ago, Carvers Gap said:

When I look at the 12z Euro operational, that ridge out west is not going anywhere.  Looks like repeated shots from the pole into the EC.  But I can almost guarantee that the EPS builds heights over the EC again.  When I look at the operational...it doesn't look like it is going to do that at all.

We’ve just gotta get to January 12th and see where things go from there.  Where’s a time machine when you need it!

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Hindcast Weeklies are rolling is rolling.  You ought to see what hindcast tries to spell check to...  Anyway, looks like the Weeklies have held serve.  The last three out of four runs(minus the cold outlier head fake) have looked pretty similar from mid-Jan on.  There is no pushback of the pattern change.  The actual transition is now just beyond the reach of the EPS by 48-72 hours.  The 12z EPS actually looked like it almost made the bridge.  I will note that sometimes the temps on the hindcast and regular Weeklies do differ.  The 500 pattern is usually fairly identical.  I think Holston's gif(weeks 3-7 I think) gives a great look at the evolution of the better-late-than-never pattern.  Between days 11-25, there is nearly a complete Western Hemisphere, high latitude reversal to a more favorable blocking pattern.  That is now within reach and less in fantasy range.

Update 1:  Coldest 2 meter temps are centered over the Rockies though the eastern half of the country transitions to BN heights.  Honestly, it looks like a La Nina setup in some ways with cold centered over the Rockies.  The temp structure may very well line-up w the MJO...I haven't looked.  Those 2m temps are here during week 4 through the rest of the run...and the worst of the cold moves east with each week.  Very similar look...maybe a bit better at higher latitudes.

Update 2:  Still talking hindcast stuff...it does begin to dry out.  I know many will roll their eyes.  Cold and dry.  I highly doubt Feb goes dry during El Nino, but it might very well be a good indicator of just how cold the air mass is that is over much of North America excluding Alaska and the Davis Straits areas.  It also implies that source region will be very cold once the pattern establishes itself.

Update 3:  The "non-hindcast" Weeklies do not have the coldest temps over the west and do align w the models 500 maps...meaning more cold in the  East.  Day 18-25 is the transition.  Jan 24-31 is cold.  Pretty much the same as the last run...I think.  It is pretty cold air from then as evidenced by BN precip due to a trough w very cold air spilling into it.  

Update 4:  The control is again glacier like for snow...but that flips all over the place so don't get overly worked up there one way or the other.  The snow mean is slightly less.  Again, I would be shocked to see 4-6 weeks of dry during later winter during a Nino...but this winter has not behaved.  So, who knows.

Update 5:  Really evolves to a very nice winter pattern with a -NAO and -AO(controls of those indices were ridiculously negative w the AO off the chart) around Jan 20th.  The 500 pattern begins flipping around January 20th.   The blocking over the top is supported by the recent SSW, potential MJO rotation(boy, that is a shaky index to lean on!), and weak El Nino, late season climatology.  Finally, I am still not entirely sure that its daily means are supported by EPS.  So there is that.

Please remember to take these with a pretty good sized grain of salt...still a somewhat impressive run given how terrible the Euro looked last night.  That is probably way too much analysis of the Weeklies...but like the SSW on Jan 1, it is the only game in town.  It has been a rough stretch of winter when we are having to analyze the Weeklies on January 3rd and hope its weeks 3 onward verify!

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Now that we have a something sort of like a consensus (yay!) between 10 and 15 days (sorry for the first image in the top gif, it is the initial one) EPS/ GEFS/ GEPS in that order:

giphy.gif 

giphy.gif

giphy.gif

(by the way I love the GEPS's PNA/EPO combo)

now I think the question is, does it transition earlier, or is there a slight delay, even beyond what the models show now? 

Whatever is happening with the strat. has yet to finish. I've basically given up figuring how/ when that impacts us, but I suspect its full implications won't start to be seen until close to the 20th. (EDIT: Scratch that, Masiello just flat out said that the Strat jet would couple with the Pac jet and eventually weaken the tropospheric component and turn it more "meridional" that is S to N over the NE PAC. If we want a bigger PNA/ EPO, that ought to help.....if I'm interpreting it correctly)

(ninja'd) SOI is -20 !!!!!!! today.  How does the dreaded tropical convection play into al this going forward? 

 

 

 

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Honestly, I was surprised a bit this AM.  The GFS, FV3, Euro, and CMC all depict the first cold shot rolling through on Jan 10ish which is now d6-7.  Then it looks like some back-and-forth as the pattern breaks towards a trough forming in the EC.  Not going to spend much time with specific analysis until they show this look for a few runs.  That said, the reversal of this pattern on operationals and ensembles that include the GEFS/GEPS is depicted to be quicker this AM.  The EPS is notably slower, but it may be missing some amplification(ensembles wash specifics out sometimes).   Its control matches the more progressive/aggressive reversal.  And I am not discounting the EPS...because it now changes around d14 at 500 w a new eastern trough forming then.  However, at d6 its 2m temps begin to go BN w back and forth.  Then, oddly, the 2m temps go warm under its new 500 trough - likely problems with source region or the EPS is playing catchup w MJO phases and/or amplification IMHO.   The good news is that the EPS matches the Weeklies run from last night in its timing.  That is the first that we have seen that in some time.   The big change this AM is that the transition has sped up on some models, and on some runs even within the European suite.  Need to watch that trend to see if it holds.   That would fit the noted SOI drop by tnweathernut and holston.  Also, it may very well be that the modeling is now seeing the MJO move at stronger amplification through colder phases.  The wild card is how much the SSW impacts the troposphere.  My guess it that it is.  Not going to put a ton of stock in recent trends as we have seen those consistently get delayed/reversed...but there are trends now well within d10 in terms of transition type stuff.  

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1 hour ago, Holston_River_Rambler said:

Now that we have a something sort of like a consensus (yay!) between 10 and 15 days (sorry for the first image in the top gif, it is the initial one) EPS/ GEFS/ GEPS in that order:

(by the way I love the GEPS's PNA/EPO combo)

now I think the question is, does it transition earlier, or is there a slight delay, even beyond what the models show now? 

Whatever is happening with the strat. has yet to finish. I've basically given up figuring how/ when that impacts us, but I suspect its full implications won't start to be seen until close to the 20th. (EDIT: Scratch that, Masiello just flat out said that the Strat jet would couple with the Pac jet and eventually weaken the tropospheric component and turn it more "meridional" that is S to N over the NE PAC. If we want a bigger PNA/ EPO, that ought to help.....if I'm interpreting it correctly)

(ninja'd) SOI is -20 !!!!!!! today.  How does the dreaded tropical convection play into al this going forward? 

 

 

 

Thanks for posting these.  Great visual representation!  Would be awesome if the pattern transitioned a few days quicker though I know that's not typical.  Usually a strong pattern in the Pacific is much tougher to break down and why models will throw several head fakes before actually getting there.  Like you, I have little knowledge of all things strat.  It's hard enough to read through the strat experts tweets/postings and interpret what they are trying to say, much less know by looking myself. lol

The very basic understanding I have of the SOI is depending on whether it's predominantly positive or negative it lends itself to either El Nino (negative) or La Nina (positive).  Related to these positive and negative phases are areas of convection in different parts of the Pacific Ocean, depending on the phase.  In short, the phase determines where the warmer waters are placed and the strength of the trade winds. 

It makes sense (to me, lol) if you can change the location of the consistent convection that has been partially keeping the Pacific a train wreck and the MJO stuck in neutral, you have a chance to alter the jet above it and by extension the pattern for North America.  

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