Eagle Eye

Very good ECM run... No complaints or complicated weather phenomenon. That's all I have to say just a very good run... Edit: Wrong GIF

Realistically, the background signals will be staying relatively steady over the next few weeks and so a major pattern flip to a sustained +VE NAO is unlikely, instead a continuing risk of that -NAO will likely be there. Initially, we may see a weakening of the AAM but a steady rise as we go into December looks probable, with one of the CFS members going for a fairly strong AAM. The main reason seems to be that we are about to enter GWO (Global Wind Oscillation) phase 8 which is associated with negative friction torque and so the AAM decreases as some of the momentum goes into the oceans and/or earth. Just beyond that and the GWO signal may be quite weak but it should re-emerge and start increasing the further we get into December. Remember that there is a lag of probably about a week between the AAM and it's correlated products. What all of this means is that I think that for now, surface components will determine how this plays out, the blocking to potential -NAO signal at the moment from the WAA is there with that Nino (positive) like AAM helping it. We then go into a state of sort of neutral where the pattern may become quite messy for mid term trends before we re-emerge in early-mid December with a similar pattern to now and a steadily improving (for someone who wants cold) GWO phase. So a return to the Nino-esque AAM is looking very likely. So for now, the next one or two setups from the MJO phase 6 and 7 recycling, probably followed by a transition period that may only last a few days before a return to the increased risk of -NAO around mid December. All in all, this is a very good setup for someone wanting cold as it means we have multiple opportunities and are in no real rush for a -NAO and can afford a slow transition.

I've been saying it for a while now, the background signals look to almost constantly be in our favour. MJO recycling through phases 6 and 7 causing the Nino AAM, trend towards a -NAO, there is very little wrong with this... Blocking seems highly likely with this sort of setup, beyond that and it's up to the strength of WAA to decide our fate, all I'm saying is that we're in with a very decent chance here. Plus Oh and above average SST's in the North Sea, lake effect snow possible in right setup, etc.. Just nobody say anything to your friends and family otherwise the net weather jinx may continue . The models will toy with our emotions of course, it just wouldn't be the GFS, ECM or any other model without any drama.

ECM 00Z was actually really good for cold air mixing in from large scale WAA pushing the blocking up much quicker than the GFS in a relatively close term into a very -NAO looking pattern. So I'm now waiting to see what the 12Z will be like.

I think it mainly has to do with the capital being warmer mixing in with the typically colder low-pressure systems and so compared to its surroundings there is a stronger temperature gradient and the atmosphere wants to be in Local Thermodynamic Equilibrium and to do that it moves upwards with more force so the cloud heights will theoretically be higher and taller clouds tend to produce more rainfall. Specifically today and it seems to also be partly associated with a lobe of PV on the back edge of the front and what I discussed in the previous paragraph with the capital able to trap more heat.

Exact modeling aside Look at it on the face of it; MJO constantly recycling through phases 6 and 7, therefore a Nino-esque AAM regime, that way the westerly jet is slowed down. What happens when the westerly jet is weakened? 1) The amplification of oscillating waves gets stronger. 2)Warm Air Advection pushed up the waves 3)Blocking 4)If it gets close enough to the Arctic or even just to Greenland then... 5) -NAO due to pattern flip. Of course this doesn't happen every time But with more chances the risk of a -NAO from at least one of them increases. Of course a -NAO doesn't always bring cold but it increases the chances significantly. Not only that but WAA near the Arctic increases vertical Eddy Heat Flux. So the SSW chance increases. Without the current modelling flips and changes. There is a signal of some sort of blocking, mainly focused to the North of us, perhaps to the North West. Take it on the face of it and its very good as an initial setup.

You don't even have to go that far to see a good setup that could lead to an eventual -NAO. There's nothing to be really negative about here and the potential is still there just being pushed back. Remember that even the 40°C got pushed back by 4 or 5 days depending on where you say that the signal was picked up.

Direct quote from one of my posts in the model discussion as we head into Winter For reference -NAO is a typically colder pattern The AAM is the Atmospheric Angular Momentum A Nino AAM is where the AAM consequently weakens the westerly winds and so stronger undulations and taller blocking high's can occur and is associated with an increasing chance of a -NAO because with a strong high WAA(Warm Air Advection) that can occur towards Greenland and on the other side of that, with little to no Atlantic influence, cold air can fit in from the North and/or from the East. "I tell you what, there are quite a few members going for that -NAO. I think the best chance for the foreseeable future is almost definitely to do with that WAA associated pattern flip, that may block out the Atlantic with a Greenland high and that's where the -NAO comes from. Beyond that and we may keep getting more opportunities as the MJO looks to be cycling back round and eventually that could go back to phases 6 and 7 again and so we get that associated Nino AAM which brings forth the -NAO increased chances. Even then, the increased Eddy Heat Flux associated with vertically propagating waves and a SSW is still not off the cards. I don't think it'll be boring model watching."

Time is most definitely on our side, slow moving MJO phase 6/7 and it's associated lag correlations and then recycling back probably by mid December. The associated Nino AAM is probably going to be quite persistent, you would expect that at some time that pattern flip to at least a part easterly has to come and I'm all for it and I think it may be worth the coldies getting just a little bit excited. We may have to wait a while but there should be plenty of opportunities. I think if you told coldies that we would enter a La Nina Winter like this, they would bite your hand off for it and this setup has genuine teleconnection backup. The impacts of climate change can be discussed as the Arctic and surrounding areas (I think) is warming faster than anywhere else but for now I think the thermal gradient is enough for that WAA to occur but where and when is up to the models to decide.

I tell you what, there are quite a few members going for that -NAO. I think the best chance for the foreseeable future is almost definitely to do with that WAA associated pattern flip, that may block out the Atlantic with a Greenland high and that's where the -NAO comes from. Beyond that and we may keep getting more opportunities as the MJO looks to be cycling back round and eventually that could go back to phases 6 and 7 again and so we get that associated Nino AAM which brings forth the -NAO increased chances. Even then, the increased Eddy Heat Flux associated with vertically propagating waves and a SSW is still not off the cards. I don't think it'll be boring model watching.

I find the 18Z very unlikely overall just with how the low's interact but that may be my bias coming in, if the 0Z and 6Z are back to normal, we can pretty much say that it's an outlier but for now it is what the models are showing. Positives are that is reaffirms the blocking and WAA just a little later so it's not all bad especially with the cold air just in the near continent. Still a future -NAO opportunity it just feels a little bit off this run if you know what I mean, as in, it doesn't seem the natural evolution from here.

Thank you, I've focused mainly on the weather learning for the past 2 years and in recent weeks have been forcing myself to read 1 high level document per week and then discuss it on here and hopefully it's starting to pay off as I'm pretty much the forecaster for my school so people will get very annoyed if I get something wrong .

I'd you were to ask me to get you a late November chart this would not be it. Very interesting setup going into Winter..

Definitely not a bad start to the crossover between Autumn and Winter. MJO phase 6-7, a faily good looking AAM, weak zonal wind. We've seen worse positions,in fact you could argue we haven't seen a better starting position for quite a few Winters as I don't think 2020/21 started like this. If we keep the up for a month or two and don't get decent cold, we'll have to have been really unlucky. We've already got 1 possible setup and we aren't even in December yet. With the MJO phase 6/7 lag, WAA is pushed up towards Greenland and possibly flips us to a -NAO style pattern over us and some early season colder air. It's very weird considering the time of year and the oceanic La Nina phase. Like I said, there are worse positions to be in. @MattH a few posts above tells the story a lot better than me, as I'm just an interested 15 year old and I'd advise listening to him this Winter.

Long term and this has been on the cards for a few runs now. Significant strat warming. I would take that. Way beyond the normal range though but the trend is there. As a general rule, the amount of EHF in the mid term coming up from the troposphere should warm parts of the Stratosphere up to those values. As a general rule of thumb this is what can be expected in a way. This is shown well by today's GFS cross-section so we're not in a bad position right now but of course it's still too far away. Just another case of the waiting game in the Stratosphere, let's hope its worth it. Surface modelling looking good for cold, Stratosphere modelling looking good for a potential split or SSW. It's only the last few runs but if you're a coldie, I wouldn't complain about the latest few runs.

You can see the large scale WAA near Iceland in the mid term on the latest run of the GFS. You can see that on the height anomalies, keeping the Atlantic at bay and in a decent position for a quick flip from the previous few days NAO+/blocking to a -NAO. That's shown well by the cold air sliding in,this is a very good run if we want a pattern change and that sort of Rossby waving is bound to weaken the zonal winds. Its even a good position for the thermal gradient to be high enough for its strength to be good enough to significantly affect the Stratosphere. If this were right into Winter, this could deliver proper snow if there was a bit more precipitation associated. Most of how cold it gets will be to do with how cold the cold pool gets and how far it can advance of course. The eventual cold pool actually starts getting quite strong early on in the run (purples) but it weakens of course as it slides across Europe to us. The 850s really do look decent though. A proper easterly. And we have the Meteociel charts showing the high blocking the westerly jet mid run with the MJO phase 6-7 lag, Nino state AAM, weakened zonal winds below the Stratosphere. Its a very good setup if it can be pulled off. It is only 1 run though but it's a step in the right direction. One small step fot the high. One giant leap for the early Winter prospects.

*Some of this is just how I've read parts of the thread and I may have understood wrong, I do that often. With the Nino state atmosphere and disconnect from the oceanic Nina and mixing that in with MJO phases 6 and 7 as lag correlations and in your head you will get a fairly good example of what the models are showing now. With amplifying jet undulations stronger due to the less westerly zonal wind, warm air advection(WAA) occurs and so it is pushed up. This is a fairly good broad early setup for a decent -NAO in general. So there's no real reason to not believe the models at the moment but it's still too far away and it's only a general idea we've got at the moment. Phases 6 and 7 don't always bring a -NAO, they just have higher potential compared to the rest of the MJO phases. Almost all of this will have a lot to do with the strength of the westerly jet, the weaker the westerly jet in the Troposphere, the more WAA there is and the better the chance of a -NAO. The evidence for a -NAO is fairly good, Nino AAM, MJO in the better phases, slightly weaker westerly winds in the troposphere than last time but everything may not coincide. We've seen this before but that doesn't mean we can't ramp it. Every time is a different time, the setup is convincing enough and the teleconnections are showing good signs so there's a lot to be hopeful for. Just don't get too worked up if it doesn't come off, we've got a long time left of potential widespread cold opportunities to go so it wouldn't be that bad. Late into November and early December is probably going to be our best chance. Weaker Surface to Tropospheric zonal wind, MJO lag correlated with MJO phase 6/7 and the consistent Nino AAM. Looking beyond this and the EHF anomalies forecasted are looking a lot better, with strengthening vertical propagation in the mid term on both of the main models. Still too far away though. Think it's a case of too far away for the upcoming chance and too far away for any recognisable SSW chance so it's the waiting game for now.

Surface flooding earlier in Ashford enough to go onto the pavements as the car shows. 20221121_153715729_001.mp4

This week on Olivia chooses: A document going into Stratospheric Eddy Heat Flux events in an idealised model Luckily it's a document that can be summarised in only a couple paragraphs as it's almost entirely what I've said before. As discussed before, the coupling between the troposphere and the stratosphere is one of the main forces in the Winter circulation. This is often shown by the Eddy Heat Fluxes on weather models. These denote the change from the zonal mean (Eddies). Positive values denote vertical wave movement. Reanalysis studies showed that accumulating strong Eddy Heat Flux(EHF) anomalies occur prior to a SSW. Extreme stratospheric eddy events are shown by "extreme positive zonal-mean wave-1 meridional heat flux values" compared to January, February, March (JFM) values. JFM used because that's when wave-1 amplitudes are at their highest. The results of the experiment confirmed that it was mainly tropospheric Eddie's where the wave interaction and therefore the main part of EHF vertical propagation occurs and that the Stratosphere isn't the main place of specifically wave-1 interaction. So, we look to the future now and at the wave amplitudes. Wave number 1 looks to dominate just past the 1st of December on the boundary between the Troposphere and the Stratosphere and that should increase coupling going into mid December with the upper-Stratosphere. From the 17th November on the ECM, there really is no solution for now, it's a 50/50 but I'd like you to note, the weakening of the 10hPa values coming up in a few days wasn't really showing until the 10th/14th November runs, before that the trend was for it to continue to trend upwards with only a few ensembles showing down, much more are showing a downward trend this time. I think it's a case of too far away for now. The EHF anomalies just beyond the first on the forecast part (far right) looking quite strongly positive and propagating vertically, not a bad position to be going into proper Winter in, definitely could be worse. The NAM at the surface looks to be moving towards strongly negative for really the first time since we got into possible proper cold and snow territory. Beyond the surface and we have a short negative NAM in the Stratosphere and another one heading for the Stratosphere into early December,. Generally a negative NAM is better for cold here and I imagine in turn, warmer over the Arctic, so if we can get a strong negative NAM in the Stratosphere, that could be indicative of a possible future SSW but for now way too far off to tell and I am definitely not saying we're getting a SSW, it's still on the unlikely end of solutions.I think my 35% chance is probably a fairly accurate representation.

Mushymanrob ramp... Do not get excited... Do not get excited... Alright, I'm a little excited. Stay tuned mid term, the Stratosphere is getting interesting... Then slightly further on and we have the EHF's in the Greenland-European area ready to continue to affect the Stratosphere. And that's shown by a relatively well-placed Stratosphere.

With my mocks this week I've had no time to read and summarise the document I asked Olivia to choose for me so I've got tonight and tomorrow to read "Dynamics of Anomalous Stratospheric Eddy Heat Flux Events in an Idealized Model", sounds err difficult. I'd just like to point out to you, the incredible snow in North America. 50 inches of snow in Hamburg, NY measured by Reed Timmer around 22 hours ago. The cold The move to cold over 2 weeks or so I know there's different dynamics over here but I hope this shows you that things can go from 0-100 relatively quickly with just a few things in your favour.

There's lots to be positive about and I certainly won't be writing Winter off yet because there's so many opportunities, a lot changes in just a month and Winter is 3 months with the occasional added bonuses of March and sometimes early April. As long as we remain in an AAM nino state and the MJO keeps recycling to MJO phases 6 and 7 especially phase 6 it is a genuine possibility and of course a SSW is not off the cards. Even in a Nina AAM state it doesn't mean that we can't get snow I just think that in these coming years, take every snow you get and enjoy it and maybe, we'll get another 2010 in a few years, maybe earlier, if we're lucky .

We are now very close to the Scandinavian wave which can just about be seen at the tropospheric level earlier on with the EHF anomaly increasing as it propagates vertically and looks to almost essentially couple and increase that Siberian flux in the mid-term. You can see that in the increasing Siberian heat on the 10hPa forecast. The polar vortex structure especially in the tropospheric levels looks to be moving towards a splitting although further up and into the Stratosphere, it's normal for now. Although, the trend is for the 10hPa zonal wind to substantially weaken beyond the 20th before recovering towards the end of the month. beyond that and the ECM (outdated) suggests quite a varied possibility although the initial weakening masks that fact that around 50% of ensembles are going for a below average/average zonal winds early in December. The MJO composite of phase 7 is very similar to how the evolution of the US recently has gone, with a lag correlation of about 5-7 days and then another 7 days to cross the Atlantic and phase 8 for their evolution over the next few days. So we'll soon start getting a similar composite to phase 7 and 8 as the MJO looks to be having quite an effect on the US weather based off that composite although how much a nino AAM state has affected that cold evolution could of course be debated. Forecasted outgoing longwave radiation suggest that we are currently around a similar pattern to phase 5 which we are and then we should move towards phases 6 and 7 based off the composites. That's well shown by most of the ensembles for the GFS. Phase 6 having an increased possibility of a -AO compared to the other phases and that's shown by the lagged response of just above 50% of ensembles forecasting a -AO by the time we get to early December. So I think an increased chance of cold early December because as a general rule of thumb a nino state atmosphere and MJO composite phase 6 typically have cold response patterns.

Absolutely fantastic morning sunrise, best in a long time here. Couple portrait photos because I wanted to get the reflection in the road properly in.

Happy birthday, hope you have a good day.