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Medium/Long Range thread


HM

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Pretty decent +AO starting to build.

e4yve5y5.jpge3y5urep.jpg

The "good" news is, bc of the PAC ridging, the orientation of the PV is able to spill cold air SE towards southern Canada, New England.

u7yreguj.jpg

Not sure how far south it can spill south towards 40N with the NAO block

Beginning to break down. This should become more telling as the PV really starts to constrict and get it's act together.

jyqupyhu.jpg.

I guess getting the PV together isn't too much of a concern right now. However, as we head into late November- early December, we'll see how cold the stratosphere becomes (+AO).

As you can see from the 2012 timeline, a feb strat warming event (MMW?) occurred, and the result was a pretty cold spring. Then we can start talking about wave breaking, EP pole flux, mountain torque as precursors to those events.

y6uteteb.jpg

The thing that can really throw a wrench into the chillier forecasts is if the PAC ridging retrograde a far enough west to allow a cut off low in the SW to pump up heights on the east coast as the -NAO relaxes (which is what some models are showing ie; euro,)

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You have to look at maps that are not zonally averaged :)

That said, the Pacific sector dominates these maps due to the Tibetan plateau and East-Asian jet. But those things have downstream effects across the CONUS in terms of Pacific blocking and the activity of the STJ in the East Pacific and across the CONUS.

It'll be easier to see this stuff in real time as we head into winter. You're asking good questions, so keep bringing them up and we'll discuss them as they become relevant.

The current Himalayan torque, if I am reading it right should ripple its way to us in early November?  (It doesnt have a hand on the next week or so?). 

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You have to look at maps that are not zonally averaged :)

That said, the Pacific sector dominates these maps due to the Tibetan plateau and East-Asian jet. But those things have downstream effects across the CONUS in terms of Pacific blocking and the activity of the STJ in the East Pacific and across the CONUS.

It'll be easier to see this stuff in real time as we head into winter. You're asking good questions, so keep bringing them up and we'll discuss them as they become relevant.

You will be sick of this by the end of november  with all the AAM questions lol.

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We were talking about this in our subforum, but 50mb is cold across central and eastern Siberia. The composite years for November and cold strat aren't going to give you a tingly sensation that's for sure. Hopefully we can get a little warming later in the month and heading into Dec. 

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We were talking about this in our subforum, but 50mb is cold across central and eastern Siberia. The composite years for November and cold strat aren't going to give you a tingly sensation that's for sure. Hopefully we can get a little warming later in the month and heading into Dec. 

 

The potential for well above normal temperatures in the MW and NE is heightened 11/15-11/25.

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Why is their such a difference in the mjo plots from roundy compared to the rmm? If I'm reading the roundy plot right we should be in phase 3 heading to phase 4 in beginning of november. While the rmm stuff has phase 1. Do the rmm plots have a lot of noise in them? While roundy doesn't?

 

ROundy is more of a stat type progression of the MJO whereas the RMM plots use OLR, 200mb VP and 850mb wind anomalies. So, sometimes what happens is that one varaible can over power and give a false signal to the MJO and make the wave appear stronger or in a different area then in actuality. Maybe some sort of CCKW is triggering the convection and not the actual MJO signal. This will give a false OLR signal for example. I mean look at the GFS vs euro  dynamic MJO plots. It's a joke.

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ROundy is more of a stat type progression of the MJO whereas the RMM plots use OLR, 200mb VP and 850mb wind anomalies. So, sometimes what happens is that one varaible can over power and give a false signal to the MJO and make the wave appear stronger or in a different area then in actuality. Maybe some sort of CCKW is triggering the convection and not the actual MJO signal. This will give a false OLR signal for example. I mean look at the GFS vs euro  dynamic MJO plots. It's a joke.

They are actually getting a little closer... last week the gfs had a strong wave heading into phase 8 then 1. While the euro kept it in the COd and had it emerging into phase 1-2, but no where near as strong of a wave as gfs.

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They are actually getting a little closer... last week the gfs had a strong wave heading into phase 8 then 1. While the euro kept it in the COd and had it emerging into phase 1-2, but no where near as strong of a was as gfs.

 

I mean more in the sense of a big divergence in forecasts. Yeah, I remember how far apart they were. I know Adam is big into Roundy's plots and they do seem a little less erratic, but they have been wrong before too.

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I posted this in the sne forum to but...The euro ens at day 10 h5 anomaly looks like it would send down another shot of cold air for the first week of november. Looks interesting in terms of keeping the east below normal. You have split flowish in the west, with a cutoff in the sw and ridging in the pacific northwest into canada. You have an erroding -epo and a north atlantic ridge which is bottling some chilly air in the eastern third of the US. Only scary thing is there is a pv lobe that is rotating slowly down towards alaska, while another is parked over greenland.

 

If that pv lobe gets into alaska and sits there almost bank on a warm stretch as all the cold air would be confined to central canada on north. I'm not sure which mjo forecast to go off, the rmm stuff or roundy, but if the roundy one is right after the first week of november it would propagate into phase 5/6 which are warm phases.

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pretty big difference right now between the euro ens mean for halloween into that weekend and the euro operational.. Euro ens mean has highs in the 53-57 range, while the euro op is 65-70

Here's why:

12z euro op @192 hrs:

e2u6a7ad.jpg

12z euro ens @192 hours:

yrytupa7.jpg

The op ejects something from the SW, and induces cyclonegenesis in the south central state. With a more pronounced low down south, a get the torch side of the low. (Op cuts it straight up to the lakes)

Not sure if the ens isn't picking up on that lp, or if the op is off it's rocker.

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ROundy is more of a stat type progression of the MJO whereas the RMM plots use OLR, 200mb VP and 850mb wind anomalies. So, sometimes what happens is that one varaible can over power and give a false signal to the MJO and make the wave appear stronger or in a different area then in actuality. Maybe some sort of CCKW is triggering the convection and not the actual MJO signal. This will give a false OLR signal for example. I mean look at the GFS vs euro  dynamic MJO plots. It's a joke.

Hey gang,

 

There's alot going on that is causing different results for MJO location depending on the variable or method you choose to observe the MJO. Roundy's tool is capturing a very strong CCKW that recently passed the Indian Ocean, generating twin cyclones on both sides of the hemisphere. 

 

http://www.atmos.albany.edu/student/ventrice/real_time/maps/kelvin/total/vp/indian_analyses.html

http://www.atmos.albany.edu/student/ventrice/real_time/timeLon/r.indian.total.30.5S-5N.gif

 

There's also a strong CCKW that pushed over the East Pacific this past week (aiding in the genesis of Raymond IMO), and will likely continue across the Atlantic this week.

http://www.atmos.albany.edu/student/ventrice/real_time/maps/kelvin/total/vp/pacific_analyses.html

 

With two competing strong CCKWs in close proximity, real-time multivariate MJO indices are going to struggle here with depicting which CCKW will be the most dominant feature. It was originally tracking the leading strong CCKW, but then jumped into the inner core as the second strong CCKW developed over the East Pacific and the leading CCKW weakened, causing the forecast to focus purely on the second CCKW. But the observations keep coming in with keeping the leading CCKW stronger than what the models anticipate, thus we are beginning to see the RMM indices skew towards phases 4-5, but still well within the inner circle

 

ALL_emean_phase_full.gif

 

 

 

Now the leading CCKW will likely soon weaken as it is currently interacting with the Maritime Continents that could induce some friction and help attenuate the wave. I expect the RMM indices to take a similar route as the models are depicting but maybe not so aggressive with the amplitude into Phase 1. It all depends on if we see a strong response to the second CCKW over South America.

 

u200.GFS.anom.KELVIN.5S-5N.png

 

 

 

I'm feeling we are already in a pretty good Phase 1 (Atlantic Ocean) type event, moving into phases 2-3 within the next couple of weeks. This would line up with Paul's analysis around that time.  I'm feeling we are ready to see a drop in AAM (a la the GWO phase space diagram), maybe a Tropical cyclone or two over the Indian Ocean, where both sides of the equator are open for business.  

 

gfsgwo_1.png

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ROundy is more of a stat type progression of the MJO whereas the RMM plots use OLR, 200mb VP and 850mb wind anomalies. So, sometimes what happens is that one varaible can over power and give a false signal to the MJO and make the wave appear stronger or in a different area then in actuality. Maybe some sort of CCKW is triggering the convection and not the actual MJO signal. This will give a false OLR signal for example. I mean look at the GFS vs euro  dynamic MJO plots. It's a joke.

Mike V has shown that removing the OLR and adding U200 is a better approximation for the MJO. Since it's hard for the models to properly parameterize convection, any image that is using OLR from a dynamical model is going to have a tough time recreating the Wheeler/Hendon plots. I also think MJO forecasting is kind of where hurricane track forecasting was in the 80s/90s. The stat models right now are a bit better than the dynamical models (though the Euro ENS and weeklies have previously shown skill).
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There's also a strong CCKW that pushed over the East Pacific this past week (aiding in the genesis of Raymond IMO), and will likely continue across the Atlantic this week.

http://www.atmos.albany.edu/student/ventrice/real_time/maps/kelvin/total/vp/pacific_analyses.html

 

With two competing strong CCKWs in close proximity, real-time multivariate MJO indices are going to struggle here with depicting which CCKW will be the most dominant feature. It was originally tracking the leading strong CCKW, but then jumped into the inner core as the second strong CCKW developed over the East Pacific and the leading CCKW weakened, causing the forecast to focus purely on the second CCKW. But the observations keep coming in with keeping the leading CCKW stronger than what the models anticipate, thus we are beginning to see the RMM indices skew towards phases 4-5, but still well within the inner circle

This is a key point. Mapping onto the RMMs can be skewed by non-MJO convective waves in the tropics.
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Or you could just listen to Mike because he's the expert

That would be my approach.  It also explains why confidence in the CPC phases are so low for some phases, probably because we are not really in those phases. That MJO teletrainning a while back, CPC was more into 200mb VP as an indicator of the MJO than the diagram. They also said that the GFS has no skill with its outlooks beyond day 11.

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That would be my approach.  It also explains why confidence in the CPC phases are so low for some phases, probably because we are not really in those phases. That MJO teletrainning a while back, CPC was more into 200mb VP as an indicator of the MJO than the diagram.

I prefer 200VP as well.

They also said that the GFS has no skill with its outlooks beyond day 11.

:yikes:
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well, looks as if the current cool down is temporary. GFS and EURO both show a lakes cutter or 2. With the ULL sitting in the SW corners and ejecting, just as the NAO goes positive, and the pac ridge retrograding, it's a no brainer that its a cutter pattern as we head into late October,1st half of November. The Northern jet retreats North into Canada, so its pure southern stream energy being depicted on the models now. Adam's 1st flamethrower pic could be posted quite soon. 

test8.gif

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