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November 2019 discussion


weathafella
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37 minutes ago, jbenedet said:

Agree on this, and it’s also why I strongly favor the first (day 3/4) wave. This wave appears to have tropical characteristics while off the SE coast. This is key. The quasi-tropical nature of this disturbance early on, means minimal long wave interference to UL ridge amplification induced by the second wave, allowing the coastal disturbance to track up the coast and phase near the BM as it becomes extra-tropical

And it actually looks ( when tracing these wave spaces back across the N-E pacific basin in the various guidance .. ) as though there may be three wave spaces in contention mucking up the works in that general baggage L/W migration.  

One thing that sticks out to me in this on-going monitoring/assessment effort for that period is that the L/W circumvallate is getting more intense over all, with gradients and wind mechanics.  Eventually, if that continues .. that will play into resolving this maybe. It will limit the weaker wave's ability to express forcing ..and than that would feed-back in allowing which ever one is dominate to be that much more conserved.  Fascinating... But that's a storm potential in there in my opinion...  either way. It's a matter of amplitude and temporal-spatial, as well as placement ... but, I think the active regime is higher confidence in itself. 

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10 minutes ago, Typhoon Tip said:

This is sort of coming out of left field ... but, I'm curious what the stratosphere -tropospheric monitoring is going to unfold like over the next month. 

We are passing mid autumn.  In my research of this subject matter over the years, if there is going to be an earlier season sudden warming event, typically by the last two weeks of November, there are signs in the temperature monitoring, where there are small positive anomaly masses that start popping off in the 5 to 30 hPa sigma levels over upper stratosphere - sort of foreboding warnings that one is nearing, however they are related notwithstanding.   This year, so far, nadda... it is early, so not seeing them empirical to date may be understandable. I am however. a little surprised we are not seeing them at least modeled to do so - the next two weeks will be interesting to monitor.  Particularly because ...

This would seem to be a favorable season for SSW phenomenon.  Both the easterly phase of the QBO, combined with the antecedent solar minimum on-going through the summer months into early autumn should have left a lot of ozone and other atmospheric thermal trapping aerosols intact relative to solar max normals ( which extinguish more of these due to interaction with UV radiation fluxing).   Both the QBO easterly phase, and the solar minimum, correlate with +SSW anomalies.  So, it almost seems intuitive to me - anywho - that we should see an "anxious" column in the stratosphere, and earlier warm nodes in temperature begin to formulate over these next two to three weeks - which is consistent with other active years going back to 1979. 

Everything is really flat. The GEFs modelling at all sigma levels, right out to 240 hours, show zero modulation of warming burst behavior.  Nor are there wind anomalies in the u-component, so there's less retrograde associated with terminating WAA at high latitudes/altitudes - which may be the problem... I think as of Novie 15, in a season such as this, with strong QBO and solar min correlations leading, we really should be seeing more warm nodes but if the circulation of the hemisphere is failing to terminate planetary waves up N, there may not be any way to deliver warmth into the stratosphere's favorable thermal layout - interesting. 

Just to remind folks... Sudden Stratospheric Warming is pretty much exactly what that says... Rather abruptly, a warm plume of air gets detected.  This plume of air usually goes on to do one of two behaviors:   comes in and out of detection as it rotates around the axis of the mean PV at earth curvature altitudes ( ha );   does the same thing, however, begins "down-welling" toward the lower levels/tropopause.  The latter is necessary for correlation with -AO forcing - which is a lengthier explanation on how/why that is the case.  But, there is a time lag of about 20 to 30 days.  If the plume descends in altitude and interacts with the tropopausal depths, that whole process takes a couple of weeks to complete, and as the statistics over the years of monitoring show, -AOs were 21+ days in the making.   If we look at the past years..there are plenty of warm plumes that suddenly materialized, but did not descend in this typical down-welling behavior... So the actual down-welling is important in the total correlation model. 

Are you familar with this website? This is an incredible website put together by Zachary Lawrence which has some excellent information for stratosphere monitoring. 

https://www.stratobserve.com/

Anyways, there are some products I' not sure how to interpret. For example, 

image.thumb.png.d109e68c76d73cec936859d03a969e46.png

 

I know this displays the structur eof the SPV...I understand what potential temperature is...but what's like the overall significance? 

My guess is this is indicating a pretty strong SPV which is on the elongated side? 

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11 minutes ago, weatherwiz said:

Are you familar with this website? This is an incredible website put together by Zachary Lawrence which has some excellent information for stratosphere monitoring. 

https://www.stratobserve.com/

Anyways, there are some products I' not sure how to interpret. For example, 

image.thumb.png.d109e68c76d73cec936859d03a969e46.png

 

I know this displays the structur eof the SPV...I understand what potential temperature is...but what's like the overall significance? 

My guess is this is indicating a pretty strong SPV which is on the elongated side? 

I'm not familiar with that site -no .. .However ( and this is no judgement ) just on the surface there, it's stuff I've read heavily about in my own fascination and curiosity over the years. 

I begin discussing and writing posts, replete with cited sources and annotation of various this that and other ... very paper-like, 10 some years ago back in the early days of internet weather-related forumsphere.  Talking 2004 ... really.   I understand much of this in concept, up to the point where any further would require dropping out of the mainstream employment circuitry and seeking another career through higher education - which I'm not going to do haha.  Anyway, what that means is just that potential temperature increases or falls while starting from a given sigma level, the starting PV=NRT variables have to be changing in order to change the adiabatic surface 'potential'.  The temperature and/or pressure is usually the case in SSW phenomenon -

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2 minutes ago, Typhoon Tip said:

I'm not familiar with that site -no .. .However ( and this is no judgement ) just on the surface there, it's stuff I've read heavily about in my own fascination and curiosity over the years. 

I begin discussing and writing posts, replete with cited sources and annotation of various this that and other ... very paper-like, 10 some years ago back in the early days of internet weather-related forumsphere.  Talking 2004 ... really.   I understand much of this in concept, up to the point where any further would require dropping out of the mainstream employment circuitry and seeking another career through higher education - which I'm not going to do haha.  Anyway, what that means is just that potential temperature increases or falls while starting from a given sigma level, the starting PV=NRT variables have to be changing in order to change the adiabatic surface 'potential'.  The temperature and/or pressure is usually the case in SSW phenomenon -

Ahh...thank you! Easy enough to understand. 

Going back to your post as well...there does seem to be some room for a potential SSW towards month's end. I wonder if that's what models are hinting at and the response is the big blocking they indicate in the higher latitudes. 

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13 minutes ago, HIPPYVALLEY said:

Man, that look next week, if only we could reschedule that for mid-December it would be weenie high fives all around.

Meh...we could run through the same look in December really - ... the label of "december" doesn't really mean anything physically. I'm always a little puzzled when people say 'wait till this happens in January' - cuz, guess what?  It would look exactly like this, in January. 

It's really situation to situational... Does the system have cold or not to work with.  In this case, it does...more so than folks may be aware.  The problem - as is/was just very beautifully exemplified by this recent 12z GFS - is wave interference not allowing any one S/W embedded in that total L/W evolution to become dominant enough, where other cyclogenic parameters would take over.  This GFS run is a comical venture in how to systemically waste all potential - amazing... lol. It's got like five S/W now... seems every run since Tuesday is adding another f'n S/W for this L/W to host.   

The Euro should be interesting. It's has a couple runs over the last few that were more conserved around one S/W and more developed concomitantly with that being the case.  It's got "smoothing" schemes built into it with that whole 4-D variable celebrity thing it's got goin' on there.  So we'll see if it's trending one way or the other. 

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49 minutes ago, Typhoon Tip said:

This is sort of coming out of left field ... but, I'm curious what the stratosphere -tropospheric monitoring is going to unfold like over the next month. 

We are passing mid autumn.  In my research of this subject matter over the years, if there is going to be an earlier season sudden warming event, typically by the last two weeks of November, there are signs in the temperature monitoring, where there are small positive anomaly masses that start popping off in the 5 to 30 hPa sigma levels over upper stratosphere - sort of foreboding warnings that one is nearing, however they are related notwithstanding.   This year, so far, nadda... it is early, so not seeing them empirical to date may be understandable. I am however. a little surprised we are not seeing them at least modeled to do so - the next two weeks will be interesting to monitor.  Particularly because ...

This would seem to be a favorable season for SSW phenomenon.  Both the easterly phase of the QBO, combined with the antecedent solar minimum on-going through the summer months into early autumn should have left a lot of ozone and other atmospheric thermal trapping aerosols intact relative to solar max normals ( which extinguish more of these due to interaction with UV radiation fluxing).   Both the QBO easterly phase, and the solar minimum, correlate with +SSW anomalies.  So, it almost seems intuitive to me - anywho - that we should see an "anxious" column in the stratosphere, and earlier warm nodes in temperature begin to formulate over these next two to three weeks - which is consistent with other active years going back to 1979. 

Everything is really flat. The GEFs modelling at all sigma levels, right out to 240 hours, show zero modulation of warming burst behavior.  Nor are there wind anomalies in the u-component, so there's less retrograde associated with terminating WAA at high latitudes/altitudes - which may be the problem... I think as of Novie 15, in a season such as this, with strong QBO and solar min correlations leading, we really should be seeing more warm nodes but if the circulation of the hemisphere is failing to terminate planetary waves up N, there may not be any way to deliver warmth into the stratosphere's favorable thermal layout - interesting. 

Just to remind folks... Sudden Stratospheric Warming is pretty much exactly what that says... Rather abruptly, a warm plume of air gets detected.  This plume of air usually goes on to do one of two behaviors:   comes in and out of detection as it rotates around the axis of the mean PV at earth curvature altitudes ( ha );   does the same thing, however, begins "down-welling" toward the lower levels/tropopause.  The latter is necessary for correlation with -AO forcing - which is a lengthier explanation on how/why that is the case.  But, there is a time lag of about 20 to 30 days.  If the plume descends in altitude and interacts with the tropopausal depths, that whole process takes a couple of weeks to complete, and as the statistics over the years of monitoring show, -AOs were 21+ days in the making.   If we look at the past years..there are plenty of warm plumes that suddenly materialized, but did not descend in this typical down-welling behavior... So the actual down-welling is important in the total correlation model. 

You need to keep in mind that the negative QBO is not descending until like February, which could factor in...

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Just now, RUNNAWAYICEBERG said:

The other important takeaway is that we are seeing signs from multiple guidance for a blocky pattern developing. Good news for you and I who live in the mid atlantic. 

Hopefully it keeps showing that. Remember last winter ? It kept showing blocking but never materialized. 

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3 hours ago, Typhoon Tip said:

Everybody's a troll involved in this social media platform in their own inimitable way .. heh. 

Yeah, the idea of a blue bomb is still on the table - if anyone cares for lucid, intellectual discussion on the matter.  

As we covered yesterday, these typically do this in guidance, this behavior where they look +1 to +3 C too warm at this range, but then the guidance' shave fractions of degrees over subsequent run cycles, while establishing an isothermal synoptic profile around the NW-W limbs of the cyclonic evolution.  It can happen any time but it's more typical autumn and sprind behavior.  This is doing exactly that ... whether it parlays into what folks want ( snow ), or falls just short, both circumstances are definitely within realm of possibilities.  But the idea of a cake and glop can't be logically ruled out just yet.  

As we also covered yesterday, the biggest problem right now is the destructive wave interference that is ubiquitous across all guidance types. This is still true in both dependable vs non-dependable fringe guidance types. 

The 12z and 18z operational GFS runs from yesterday, particularly the latter of the two, were placing more of the emphasis on the 2nd wave in the total bag of L/W progression through the E - very similar actually to the 00z Euro interestingly enough.  Then of course the GFS being the GFS, the 00z and 06z have turn-coated on that thinking and abruptly begun favoring the lead "hook low" .. (which frankly looks over done either way, but definitely f's up everything no matter what way one looks at it). 

That all said, I'm not sure I'm willing to hand over the conductor's truncheon to the Euro and let it lead the way from D6/7, either.  Because A  .. this model, far superior to the GFS as it is, is not actually that much better than the GFS at this particular time range ( regardless of y'alls Lord of Flies popularity schemes).  Inside of D 5 ... yes, sure.  

As an aside,  when I was recently making fun of Kevina, I deliberately overly-stated ( solely for the intent of pissing him off and it worked! ) that the GFS schooled the Euro.  To clarify, what actually took place is that both models were abysmal in the D6/7 time lead, regarding an O.C.D. monitoring effort collectively applied to an innocuous piece-of-shit fropa. That was two events ago.  At the time, the Euro was depicting a stem-wound juggernaut bomb just E of the arm of the Cape; meanwhile, the GFS was flat and pancaked-progressive with the flow - it barely cobbling together just a weak low it rocketed utterly inconsequentially seaward across the SW Atlantic Basin WSW of Bermuda. 

That disparity lasted for oh ..a couple three cycles say.  But, at around D5, the GFS suddenly sniffed out the polar/arctic boundary and the wave along it, as it unzipped NW of the area. The model was scheduling our SNE and eastern NE regions to be tortured in a rotted polar warm sector - which of course... the model f'n nails that!  The Euro, however, was lagging in there.  That's when and where the "schooling" ( in the relative sense ) took place, as it was still vestigially trying to hold onto a Kleenex and lotion solution, which it should have abandoned.  It wasn't long after, tho.  By early on the D4 cycles, the Euro caught on and from that point forward, they more than less depicted the same shit from about 60 to 72 hours lead, held serve, and destiny was righteously occurred and the Universe didn't cease to exist because no one got snow.  ( See how that works?)     

I don't think realistically that ordeal would or should really hurt the Euro street cred.  I bet it doesn't really even show up in the verification curves either. It was just an isolated oddity in model performance, one that happened recently and just so by the love of god for the purpose of lambasting Kevin. I would still nod to the Euro as the better prognostic tool in more situations than not, particularly time frames < 5 days.  I do submit in better honesty that the Euro is dicey beyond D5 just as the models all are; I really am not sure if over our quadrature of the World, it really is all that much better than any other guidance types at D7 in a straight up comparison - I don't know.  I don't bother looking because ... just common existentialism with it, I've seen the model dump enough solutions at D7 to know it's just not dependable enough at that range so who cares.  

Which...holy shit.. We're at D7 now.  Anyway, if the models come around to damping out the lead interfering wave, that 2nd one becomes dominant, then the deeper 18z GFS/00z Euro runs have better hope of transpiring.  And then it's layered correction vectoring, because "if" that happens, then we can start figuring for the isothermal sounding to become more 0 C -like as the event nears.  Seeing as few things have to go right ... gotta put the over all odds of satisfaction potential as being higher for blue ballz rather than blue bomb for now.   Who knows.. 

 

15 minutes ago, Ginx snewx said:

Next person who quotes his entire post hopefully gets skunked on snow this year. Holy scrolling

well if I get skunked so do you hahahahaha

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