am19psu Posted January 25, 2013 Share Posted January 25, 2013 which the better (relatively speaking) RMM or Roundy? I would imagine 2 charts would be modeled with the 200mb and 850mb since storms can be low level like mike stated? Well, the RMMs are derived empirically from the data. They define the MJO phase space. The RMM dynamical forecasts are the phase space plots with the green mean line and yellow ensemble members. Roundy basically uses an empirical propagation technique based on the phase speeds of the Kelvin/MJO waves analyzed (it's more complicated than that, but you get the point). You can get the Roundy based RMM forecasts here: http://www.atmos.albany.edu/facstaff/roundy/waves/phasediags.html Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 should mention 0z euro has a coastal storm that tracks off hse and brings 2-4 into the region with more along the coast next fri day night. Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 Well, the RMMs are derived empirically from the data. They define the MJO phase space. The RMM dynamical forecasts are the phase space plots with the green mean line and yellow ensemble members. Roundy basically uses an empirical propagation technique based on the phase speeds of the Kelvin/MJO waves analyzed (it's more complicated than that, but you get the point). You can get the Roundy based RMM forecasts here: http://www.atmos.albany.edu/facstaff/roundy/waves/phasediags.html what are the 2nd row of diagrams in that link? Are they the 850mb and 200mb diagrams? Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 what are the 2nd row of diagrams in that link? Are they the 850mb and 200mb diagrams? The image on the second row on the left is the full RMM depiction of the Roundy forecast. It's the RMM translation of this. The image on the right is using the wavelengths that correspond to the MJO only (basically removing all the Kelvin/Rossby/easterly wave noise). Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 The image on the second row on the left is the full RMM depiction of the Roundy forecast. It's the RMM translation of this. The image on the right is using the wavelengths that correspond to the MJO only (basically removing all the Kelvin/Rossby/easterly wave noise). that's pretty neat. So kelvin waves can skew the mjo weaker and stronger going off that chart? Also, it looks like that chart is off on the wave strength from what has happened already. That map shows it barely above the cod, meanwhile on the other diagrams its a way stronger wave than that. Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 that's pretty neat. So kelvin waves can skew the mjo weaker and stronger going off that chart? Also, it looks like that chart is off on the wave strength from what has happened already. That map shows it barely above the cod, meanwhile on the other diagrams its a way stronger wave than that. Kelvin wave can either constructively or destructively interfere with the signal. It's just a matter of the harmonics. Because of the way the Roundy plots are constructed (only coherent wave signals are mapped), it will never end up much farther away than the COD. You have to use a different baseline in your head when you look at the Roundy plots in the phase space. Link to comment Share on other sites More sharing options...
Harbourton Posted January 25, 2013 Share Posted January 25, 2013 Thank you Tom, Mike and Adam for the great explanations. If I am reading the Roundy correctly it shows the MJO not entering Phase 8 until after February 10? Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 Kelvin wave can either constructively or destructively interfere with the signal. It's just a matter of the harmonics. Because of the way the Roundy plots are constructed (only coherent wave signals are mapped), it will never end up much farther away than the COD. You have to use a different baseline in your head when you look at the Roundy plots in the phase space. I see, so the fact that it actually gets outside of the cod illustrates its a pretty strong wave. Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 I see, so the fact that it actually gets outside of the cod illustrates its a pretty strong wave. Exactly Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 Thank you Tom, Mike and Adam for the great explanations. If I am reading the Roundy correctly it shows the MJO not entering Phase 8 until after February 10? No, on the roundy one its getting to the end of phase 7 getting ready to go to phase 8 which it should be there next week Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 Thank you Tom, Mike and Adam for the great explanations. If I am reading the Roundy correctly it shows the MJO not entering Phase 8 until after February 10? No, it's at the P7/P8 border right now. Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 Here harbourton, i circled the areas in black. Just think of it like this, once it gets to that phase 8 zone it then reverts over to the far left in the eastern hemisphere, like both sidea are connecting. So the areas circled show the current wave is continuing to move out of phase 7 and into phase 8 and 1, also weakening wave. It has a new wave which fires up, but its pretty weak in phase 2-3 that dies, and another one starting way out in time (feb 20th) in phase 1. So what this is suggesting to me, adam can verify this or correct me. The roundy plot, though it probably a little to weak on the strength of the wave, goes through phases 8-3, that wave dies and it does a loop back into phase 1-2 by the end of february. Link to comment Share on other sites More sharing options...
Harbourton Posted January 25, 2013 Share Posted January 25, 2013 OK forgot that below the green line was the current day. Thanks again! Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 OK forgot that below the green line was the current day. Thanks again! no, the green line is the current day, not below. Link to comment Share on other sites More sharing options...
Harbourton Posted January 25, 2013 Share Posted January 25, 2013 Gotcha! Link to comment Share on other sites More sharing options...
chubbs Posted January 25, 2013 Share Posted January 25, 2013 should mention 0z euro has a coastal storm that tracks off hse and brings 2-4 into the region with more along the coast next fri day night. Set-up is somewhat similar to virgastorm of a couple of weeks ago. As was the case then models are all over the place in handling the southern end of the western trough. There is low end potential if a cut-off forms in the SW and ttakes a favorable track or if the troiugh elongates and we get a well-timed secondary Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 Kelvin wave can either constructively or destructively interfere with the signal. It's just a matter of the harmonics. Because of the way the Roundy plots are constructed (only coherent wave signals are mapped), it will never end up much farther away than the COD. You have to use a different baseline in your head when you look at the Roundy plots in the phase space. This same concept also goes on at much larger time scales and with much larger phenomenon. The concept of "heightening a signal" or harmonious interaction is what is, for example, currently intensifying the warm 30mb temperatures above the Tropical West Pacific. In terms of tropical forcing, the MJO can reach the longitudes of favorable Walker Uplift that can excite the signal further. On a stratospheric sense, if a wave 1 or 2 disturbance happens during climo wave periods, these get excited and even stronger than usual. Harmonics maaan! Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 This is really a key statement here and why I keep saying HM is better at this stuff than me. I can pick out favorable periods based on making skillful MJO forecasts, HM has other things he looks at that lets him zero in on cyclogenesis. Oh, and: #climo Thanks for the nice words, oh and lol at #climo. The STJ is getting stronger and stronger each run man. Forget about the individual storms and look at how many southern stream waves are on the euro. Good stuff! Link to comment Share on other sites More sharing options...
NaoPos Posted January 25, 2013 Author Share Posted January 25, 2013 . Harmonics maaan! So thats what the HM stands for?! Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 Thanks for the nice words, oh and lol at #climo. The STJ is getting stronger and stronger each run man. Forget about the individual storms and look at how many southern stream waves are on the euro. Good stuff! Just got out of my morning briefing. One met said "MJO isn't getting to phase 8 because of the cooler water." :axe: to the m'fing Even if nothing rides up the coast, it should be ice storm city in the Mid-South first week of Feb. Link to comment Share on other sites More sharing options...
am19psu Posted January 25, 2013 Share Posted January 25, 2013 So thats what the HM stands for?! +1 Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 Now that the MJO is moving into the favorable phase 8, does a slower progression mean we will see favorable forcing for a longer period? Or is it better for it to steadily move along? I am assuming of course in either scenario the convection continues and we see a healthy wave. My perception of the MJO is always a bit slower because of the lag effect on the Mid Latitude pattern after its immediate effects on the Tropics/Subtropics. But anyway, I think we end up looping around in the phase 1-4 octants through mid-Feb. From that point on, it is a tough call. I can see everyone getting worried about a warm period, essentially the end of winter, late Feb-March as the forcing arrives into the W. Pac and the stratospheric PV reestablishes itself, causing the AO to go positive. However, I don't know if it is going to be that easy this year as it was the last few. I'll try to elaborate more at some point today. Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 So thats what the HM stands for?! LOL One day I wanted to enter a storm chat, might have been for either Jan 2000 or something before that, back in the days of NE.WX. I randomly hit those two letters and it stuck with me ever since. My name has absolutely no meaning. haha But at the same time, those days are a little foggy for me so maybe there was something intended at the time. Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 Just got out of my morning briefing. One met said "MJO isn't getting to phase 8 because of the cooler water." :axe: to the m'fing Even if nothing rides up the coast, it should be ice storm city in the Mid-South first week of Feb. Time to "tie up the loose ends" .... I agree that our brothers in the South need to pay close attention to the first round of southern waves while we freeze our nads off up here. Link to comment Share on other sites More sharing options...
tombo82685 Posted January 25, 2013 Share Posted January 25, 2013 My perception of the MJO is always a bit slower because of the lag effect on the Mid Latitude pattern after its immediate effects on the Tropics/Subtropics. But anyway, I think we end up looping around in the phase 1-4 octants through mid-Feb. From that point on, it is a tough call. I can see everyone getting worried about a warm period, essentially the end of winter, late Feb-March as the forcing arrives into the W. Pac and the stratospheric PV reestablishes itself, causing the AO to go positive. However, I don't know if it is going to be that easy this year as it was the last few. I'll try to elaborate more at some point today. I'm definitely liking the prospects for the first part of february. With the mjo in favorable phases, combined with the stratospheric warming. The coldest air is on our side of the globe. The glaam is looking pretty good for meridonal flow and some east coast storms with the southern jet becoming active. All spells to wintry times for the eastern third of the US. My only worry is that pv sags to far south and Adam worse fear of brutal cold and dry, while the south gets pummeled with storms. Link to comment Share on other sites More sharing options...
CoastalWx Posted January 25, 2013 Share Posted January 25, 2013 I'll have to read this more carefully later when I feed my son..lol. Great for killing the time. Awesome stuff in here. Link to comment Share on other sites More sharing options...
chubbs Posted January 25, 2013 Share Posted January 25, 2013 Thanks for the nice words, oh and lol at #climo. The STJ is getting stronger and stronger each run man. Forget about the individual storms and look at how many southern stream waves are on the euro. Good stuff! Great discussion above. D11 (2/5) GEFS looks promising as low heights rotate up into Maritimes with STJ coming alive Link to comment Share on other sites More sharing options...
HM Posted January 25, 2013 Share Posted January 25, 2013 It's a thing of beauty. I'm looking forward the inaccurate 12z models today. Link to comment Share on other sites More sharing options...
MJO812 Posted January 25, 2013 Share Posted January 25, 2013 Latest MJO plots Link to comment Share on other sites More sharing options...
chubbs Posted January 25, 2013 Share Posted January 25, 2013 It's a thing of beauty. I'm looking forward the inaccurate 12z models today. Its hard enough to get 1 jet stream right much less 3 Link to comment Share on other sites More sharing options...
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