EasternLI
-
Posts
3,372 -
Joined
-
Last visited
Content Type
Profiles
Blogs
Forums
American Weather
Media Demo
Store
Gallery
Everything posted by EasternLI
-
I'm kinda impressed with the way this MJO is progressing. Plus it's of the slow moving variety. Which is good in this case because those are the more likely versions to affect the circulation. Velocity potential tells a better story then the RMM charts. It's interesting too, that models continually have tried to kill this wave in extended ranges. Since November really. Yet it still continues on. These are both from the GEFS. Check out where we were and compare it to where we are headed. Effectively muting the MC region, while allowing the western hemisphere to be more dominant in the forecast period. Cold enso base state is also is also identifiable on these but not overpowering everything like our most recent La ninas have. Top image I have saved from the 12/12 00z GEFS. With a forecast ending at 00z today, the 29th. Bottom image is last nights 00z GEFS.
.thumb.png.563e336ffe6f3429109e51e200232774.png)
-
Great post. I've done a fair amount of reading on this topic over the last several years. I think your thoughts are right on the mark as far as lining up with said reading. One thing I remember seeing, and I don't remember where, is that if one is looking for an ssw to deliver a colder pattern. There's a higher probability of that occurring from one that initiated during an already colder pattern. Which sounds like it lines up with your thinking on the phenomenon and kinda makes sense to me.
-
The PDO should continue to climb too, with the progged pattern. Which is interesting. This is a 5 day mean from the 12z eps.
.png.6dac9fd2a6bca99695ed3b0031ebf452.png)
-
Impressive poleward ridging from the 18z GEFS heading into the heart of January. It's interesting also, to see the eps weeklies now weakening the SPV pretty substantially by mid January. Which would be consistent with an mjo 7 response.
-
-
I think from a very broad perspective, all of the 00z ensembles basically showed the same thing. When you loop them. The North Pacific low retrograding to the dateline. Which causes the GOA low to break on the west coast. There would be an emerging ridge on the west coast in that scenario. Or wherever that wave breaks. Eps shows the same progression. Canadian ensembles are more aggressive. This is the 00z gefs
-
Yeah, it's all making this year an interesting one to follow. I'm curious how much of that suppressed phase we can nose over into 120E or if we can.
-
The trend in recent days has the mjo continuing to slowly move eastbound into the Pacific. Gefs from 00z continuing that idea and with a decent amplitude as well. Starting to get into the phase 7 space at the end of these now. Would be great to see it keep moving, and that does look like a realistic possibility as of this moment.
-
Seems like the events of November have left the atmosphere in a more Niño-like state. If the MJO is effective in the Pacific. Probably another WWB and +EAMT in January? https://x.com/Met4CastUK/status/1864797137227387090?t=K3C8XrFImAvNwHt5_u21Mw&s=19
-
The westerly QBO theoretically could assist to temper some MJO convection in the MC region this winter. So it will be interesting to see how everything progresses moving forward. Here's some key points about this relationship. It seems like this could be a good test subject ahead of us. Modeling evidence of QBO‐MJO connection: A case study https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020GL089480 "The boreal winter Madden‐Julian Oscillation (MJO) is modulated by the Quasi‐Biennial Oscillation (QBO). The MJO becomes relatively strong during the easterly QBO (EQBO) winters but weak during the westerly QBO (WQBO) winters." "When the lateral boundary conditions are switched with those of WQBO or strong WQBO winters, the MJO becomes weak over the Maritime Continent." QBO modulation of MJO teleconnections in the North Pacific: impact of preceding MJO phases https://www.nature.com/articles/s41612-024-00565-w "It is found that the Rossby wave trains induced by MJO phase 6–7 exhibit greater strength and robustness during the westerly QBO winter (WQBO) than during the easterly QBO winter (EQBO), although the MJO itself is weaker during the former. This counter-intuitive dependency of MJO teleconnections on the QBO is attributed to the preexisting MJO teleconnections prior to the MJO phase 6–7. The MJO phase 6–7 is more frequently preceded by stronger MJO phase 3–4 during the EQBO than during the WQBO. The preceding MJO phase 3–4 teleconnections, which have opposed signs to the MJO phase 6–7 teleconnections, result in a considerable attenuation of the MJO phase 6–7 teleconnections by destructive interference." There were recently twin TC's in the Indian ocean. Pictured below on 11/27 12z. Who's influences appear to be waning currently. It'll be interesting to see how everything trends this month.
-
I have an observation to share regarding the MJO/status of tropical convection. It's been quite interesting this month. I think I can provide an explanation and illustration of why it's rendered ineffective currently. I think it's actually a really good example of a time when the MJO just isn't going to mean very much to us. The image below is from the JMA. It has OLR overlayed with 200MB VP anomalies. Note how the center of action along with the bulk of the forcing this month is south of the equator. When that happens, it's just not going to effect the NH very much if at all. It seems like this is also leaving some room for the Pacific jet to be more equatorward rather than poleward. Which I've seen you make mention of in a different post. So as long as this continues, which could certainly be debatable, I don't think the MJO is going to be telling anyone much of anything. And maybe we can actually achieve some Aleutian low this year when that equatorward jet extends like guidance is currently showing.
-
Yeah, 65 here too. It feels glorious, ngl.
-
Then the gfs spits this out after I said that of course. Clown range here, but the interesting thing about this, the eps has a couple clusters that show something similar to this too. May be nothing, but worth a mention I think.
.thumb.png.9afeb5346861609f86b80e7bdab4ca98.png)
-
Just starting today and going ahead, the ssw will now be included in the initial conditions on modeling. So it will be interesting to see what changes, if anything, as that becomes the case now. There's evidence available that suggests this makes a noticeable difference with predictability of how they play out. I'm not saying to expect anything crazy, just that this is a point where potential changes could occur on modeling. Or not lol.
-
Yeah, I've been saying it's not really impressive looking.... The latest gfs cross sections suggest this is not making much progress downward. Best to wait until it's underway and then see what models are doing, though. But it just looks uninspiring to me so far.
.thumb.png.8526cb1265f989a3dd429a52804de14f.png)
-
Toss that MJO idea to the moon. Not happening. It's not going to be effective....
-
Weaker walker circulation is just not good, maybe. We want some amplitude, but too much isn't good either. It's interesting to think about.
-
I like a weak to moderate modoki el nino next year. We're following EOF2 from the following paper fairly well. Which leads to that. I agree neutral isn't off the table just yet. Whatever it is, it is not similar to EOF1. Which leads to the east based classic events. Leading modes of tropical Pacific subsurface ocean temperature and associations with two types of El Nino https://www.nature.com/articles/srep42371
-
Yes, this is usually my rule of thumb with that. It's funny too, I thought this winter would suck back in August. Then the blocking became a possibility and I reconsidered everything lol. Because blocking is what you look for in la Nina if it's going to be any good. That was an interesting development. It failed, sometimes they do. Is what it is. Swap neutral and moderate la nina with each other and I agree. Neutral sucks, too strong in either direction does too. Just a very basic guideline. Many other variables to consider.
-
It does look like the ssw is going to actually go off. Meeting the technical wind reversal definition. In addition to the eps, the GEFS is now 100% for the past few runs now. Will be interesting to see how/if it works with the troposphere following this. Be curious to see some cross sections on what is happening once this gets underway. Never can be certain with these things but worth keeping tabs on. It's something to watch at least. Hope everyone enjoys this very nice mild Friday on tap.
.png.a0f4b36ca9d9236342b2ea87dd04c1f6.png)
-
Well, it can't get much worse I don't hate la nina. Some of them can be good. This one just has it all wrong lol. Tired of it though, I welcome a change.
-
Here's a great example of why extreme caution is always needed with those charts. If we look at what is actually occurring on the model. We can see the MJO wave moving right along. However, we can also see the warm pool convection associated with la nina never fades away enough as this is occurring. This renders the whole thing less effective. This is the destructive interference we sometimes mention. We'd really want something strong enough to fully disrupt that in order for more meaningful changes. Something we just haven't seen much this year. So that forecast crashing into the COD is really trying to say it's retaining its dominance in spite of the MJO. Which is a problem for us this year. That positioning right there is the anchor for a western trough. So we end up stuck with that as much as we are. Now, let's shift that thing closer to the central Pacific next year hopefully. Then you get a western ridge instead.
.thumb.png.234b6f282dede72c10aca3503999a151.png)
-
Not sold yet on a technical ssw even occurring. Some warming, sure, but the gefs seems to have backed down on wind reversal today at 00z. Plus, the 06z run now only has 60% of the members on board with it. So it's still possible it doesn't even occur this time either. I realize the eps weeklies were bullish yesterday. However, I'd prefer to see total agreement. Not going the other direction. Especially as we're getting inside of day 10 now. You'd really want to see a strong event too in hopes of impacting where it matters. This is just uninspiring so far IMO. I also agree with the sentiment that even if one should occur, it doesn't necessarily have to matter for us. This is always the case and should be baked into any thinking about this topic any year.
.png.a817651b5dc7eb02eb00357b34b5fa68.png)
-
The purpose of the long range pattern discussions is not to identify any individual storm systems. I personally think it's a misinterpretation to think of it in that way. You can get snow events in a bad pattern. Nobody has said that can't happen. I certainly haven't. The thing is, favorable longwave patterns offer an easier path to accomplish the certain combinations of synoptic features we're all in search of. That is the reason why they are often discussed. Not to identify anything specific. At least it shouldn't be. It's simply an attempt to identify windows where it's easier to find something specific. It's really two separate things, in my view.
-
0F IMBY currently. That's impressive here on CAA. Usually that happens with rad cooling here. Yesterdays hrrr did alright locally here. Euro too.
.png.c6e4067c40586c65f2d2df4564e3463f.png)
.png.9d3ffbf529ae480ceef5a9936e5b2e60.png)
.png.25c1381ea0daf37cf611d94415c83fbd.png)
.png.111b687e503f4719d3c833d2f0002904.png)