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Snowy Hibbo

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    Melbourne, Victoria, Australia.
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    Meterorology with a focus on long range forecasting and climate drivers .
  • Weather Preferences
    Snowfall obviously.

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  1. Snowy Hibbo

    The Seasonal Forecast Thread

    Here's my thoughts on how the forecast will go for the U.K. (And the European Alps). https://longrangesnowcenter.blogspot.com/2018/10/2018-european-winter-outlook.html Including analysis on the MJO, ENSO, NAO, Arctic domain factors, etc.
  2. So to prove your point, you show the tweet of a "professional meteorologist", asking whether the -EPO means cold. I am not quite sure about his credentials.... I would find someone else to prove your argument. And then the replier didn't support your opinion, he said it was "tough".
  3. So what is this then? Bottomline, whether the blocking is in the -EPO or +PNA domain, the downstream troughing occurs in Central and Eastern US, with the polar lobe coming down over the Mid West and bringing snow to the Mid-Atlantic/New England. And this further demonstrates the downstream effects. This is not to say blocking doesn't occur in the Eastern US, during a -EPO. I am just stating that a -EPO is correlated with a trough over the Central and Eastern US. That blocking over the Bering Sea isn't what I would call a -EPO, too much leaking into the Far East Siberian region, with the troughing off Western Canada too. That would be the WPO domain. With a -EPO and +PNA pattern, the below graphic shows Eastern troughing, in combination with other factors. Shows that there can be successful cohesion, which drives troughing on the Eastern half of the continent. Here was the EPO during your period, first half dominated by a neutral EPO, then a weak-moderate negative phase, then a weakening of the -EPO towards the end. Meanwhile the -WPO was nearly off the charts in strength, so clearly you have picked the wrong domain. The WPO and PNA domains don't cross, nor often correlate. So your statement of "HUGE -EPO RIDGE" is quite misleading. You also ignored the more -EPO like blocking from the 8-18 Sept this year, which was also a period subject to a +PNA.
  4. With all due respect, you are wrong. A -EPO's downstream effects often create a Eastern trough. That is what it is known for doing, disturbing the polar jetstream up to Alaska, and bringing cold down to the Eastern Half of the United States. A -EPO if it stretches down towards the West Coast of America often gets called a joint +PNA and -EPO. So the assertion that a -EPO must go with a -PNA or vice versa is entirely misleading.
  5. I realise I added to the case for an oceanic and atmospheric disconnect, but what if the ENSO is helping to signal, particularly with CP Nino regions being warm (along with EP Nino regions theoretically warming as well), and cold SST anomalies around Maritime Continent. This would help MJO and other equatorial waves to avoid Phases 4 & 5, and stay around Phases 7-8-1, particularly the former two phases. This is all for in terms of the winter, but can also apply to the present day.
  6. Tamara still pops in from time to time, like myself. You might have a better chance of catching her here: https://www.33andrain.com/topic/868-teleconnections-a-more-technical-discussion/ You were a tad early, but still largely right, with us now in a +EAMT event over the past few days. This as @Catacol states, we are in a +AAM phase, supported by the +EAMT and other torques. I don't expect the AAM to be very Nino-esque IMO, with SOI forecasts from the Met Office and ECMWF supporting a +SOI in Nov and Dec, supporting an atmospheric ENSO Nina-like phase. This would obviously translate to the AAM, and shows that there is potential for the Atmospheric ENSO component not to merge with Oceanic ENSO, which should be a weak-moderate basinwide event. This theoretically causes more NP-Jet extensions, which translates downstream to the UK, by methods of the GSDM. Context to this discussion here . And the +EAMT is helping a Pacific Jetstream extension over the next 10 days, according to GFS.
  7. This extract (minus a few changes for the UK) is from my latest post in my blog. http://longrangesnowcenter.blogspot.com.au/2018/02/europe-on-long-term-26th-feb.html "The GWO is currently in a negative trend. There are two options, the FT and MT torques increase, which will stabilise the GWO, like the below chart is starting to show. Or the other option is that the FT and MT torques go back to decreasing in a few days, and send the GWO into the low AAM Phases, which favours a +NAO setup. Many forecasters are favouring the latter option, so is the NWP guidance, but the former option is still a possibility with some torque data showing that to become reality. It will be interesting to see how that pans out. EPS shows the MJO moving into Phase 2, before weakening into Phase 3. Phase 3 + 10 days equals a +NAO, or a more zonal Atlantic setup. This favours more snowfall for the Northern Alps/more precipitation for the UK, but GEFS shows the MJO weakening before it enters Phase 3. EC46 like most models, is showing a big -NAO drop around the end of the month, that supports more cold for the UK. This -NAO pattern persists until mid March, and then stays mostly neutral into April. The ec46 AO forecast shows a similar result. CFS in a rare move, agrees with EC46 on both the AO and NAO. GEFS and CFS longer term, show no signs of strengthening the polar vortex. The recent SSW is currently allowing a -AO/-NAO pattern to take hold until Mid March. The Stratosphere will probably play less influence after that time. So the next 2-3 weeks will be guided by cold in Europe and the -NAO in the Atlantic. Beyond Mid March, we may see a +NAO setup start to form, under pressure from the AAM if it stays negative, and it may just generally occur also due to background factors like the sea-land gradient and the weakening yet still observable Nina base state." Here is the referenced chart of the EC46 NAO.... CFS as stated, looks very similar, which is interesting as it shows long term models agreeing on a forecast, that shows a higher degree of accuracy. What we long term forecasters are looking to, is not the SSW driven medium term forecast, but the longer term one that is more likely to be centered around the Pacific.
  8. Hey mate, would you have a link to this forecast? Thanks. Do you really think that? Because all of the NWP guidance I have seen, shows the MJO in the COD by Early March. So I personally doubt any high amplitude MJO waves occur. This would plant the seeds for your higher AAM orbit in Later March.
  9. A quick update on the torques situation. MT is deeply negative, pushed by a low EAMT, creating the Pacific jet retraction that we are currently in. FT is steadily rising, generated from a WWB in the Pacific and a Kelvin wave in the IO, however it is still in the negatives. I did a whole tweet thread on that, if you are interested. The current GWO situation brings the AAM near to zero, showing the transition from the +AAM orbit, that helped bring about the SSW, to the -AAM orbit that brings about the Pacific jet retraction. Shows how involved the AAM is.... GEFS currently shows MJO going into the COD on the 1st March in Phase 2. This would help bring about a more +FT outlook, with the MJO signal weakening in the IO. This moves to +MT, etc.... The Pacific jet retraction isn't normally very helpful for the UK snow-wise. It normally forms with the -AAM state, to create a +NAO/ zonal setup. But in this case, the NAO is going to be deeply negative, thanks to the SSW. So the Pacific jet retraction is just a consequence of the drop in the AAM. As known, the GWO's orbit into the positive AAM stages help create the SSW, as part of the dual entity that the MJO and GWO are, but with their own individual identities. Anyway my other opinion would be on my tweet thread up above. I am wishing you all bucketloads of snowfall and very cold temperatures across the UK (unless you don't like snowfall, then I guess stay next to the fireplace?)
  10. As known, the MJO is one of various reasons behind the SSW we are experiencing now (more of a influencer on extratropical patterns, but that's a story for another time). It's basically a GFS vs EC match ATM, with GFS with a stall and weakening sequence, and the EC with a more slow progression into P8&1. But longer term VP200 GFS is returning good for potential for P1&2. Apart from the benefits for Eastern troughing, this indicates a extratropical movement (to GWO p1&2), which could also improve longer term outlooks for Eastern America (First Week of March onwards...) VP200 on GFS for preview. EC Monthly and POAMA show a long period in the COD during the first half of March, so the prospects aren't great. But NWP is dicey, and anything could happen. And for that -AAM to occur, we really want a proper tropical lead, to bring MTs, et al down. EC Monthly with a P7 stall and weaken, with a tight grip into the COD, and stalling as a very weak signal. POAMA with a slower progression around P8&1 into the COD, although ending in the same conclusion as the ECMON. Intriguing current GWO conditions, with a rapid increase in Worldwide MT over the past few days. This is based upon (mostly) increases in all MT regions, with EAMT increasing and now slightly decreasing, but it is still in the negative zone. MT in the Andes and Rockies is positive and increasing, which is probably behind the spike in the MT. The FT is currently in the negatives, and with MJO signalling in the IO we should see more of this. Then we should see the trop>extratrop link that Tamara and others are talking about, the +FT > +MT. This would be much more possible with a MJO propagation to the IO. The NWP is against this however, as shown above. Will the +MT be enough to convert the AAM to positives again? Will the NWP turn up correct, and we end up stuck in a -AAM phase? Only time can help. But keep up the interesting posts from all...
  11. Aka MJO > Strat > MJO feedback loop. There's also the GWO in that equation, but it is harder to point out how it fits in. I wouldn't say really solid Niña atmosphere, the SOI has been into Niño stages at times, and now the AAM has shown Niña the door. Once we get some Oceanic feedback, we can proceed further into knowing how that impacts the later stages of the year. Stepping stones.... I am certainly not going for a big -AAM at that stage. I will be awaiting this tropical -FT
  12. While some are using Niña composites, and drawing trends to a Niña base state, here and the specialist threads, plus Twitter, etc, it is important to point out that we are slowly leaving Niña. And the +AAM has shown us that the Niña base state is moving away, and we are heading to a more neutral state ENSO wise. While MJO driven, this in itself is going to be very important in the coming month. Are we going to see another +AAM orbit soon (end of Feb/early March)? Are we even going to go to P2&3 GWO? You can't always follow GEFS and the NWP models, you have to think outside of the box, and move with the times. Potential for GWO effects into Spring will be important for setting the stones into place for the UK summer, and ultimately next winter. But let's think less big, and think about the now. A little summary.... MJO is now apparently moving out of it's P7 stall. GEFS and GEPS want a continued stall, and weakening into COD, bypassing any P8 progression. EPS and JMA want a P8 and P1 progression slowly weakening to the COD. Interesting to see which one is successful, currently GEFS is one up, with it's correct prediction of a strong MJO signal stall in P7. MT is currently slightly negative/mostly neutral, with an EAMT increase in difference with the trend over the past week, which saw a large negative tendency in the MT. This is causing a movement towards GWO Phase 8, as predicted. (Latest GWO chart: 13th Feb) With the Nina influence clearly waning, maybe we won't see a proper -AAM phase. A slower lead from FT, may be indicating a lesser -AAM stage, and a quicker return to +AAM territory. But for the interim, the SSW impacts should out-muscle the effects of the GWO for the time being, but the GWO is an important consideration going into March. What that means for the UK, is a trickier task to point out, and I'll leave that to more regional members here. The SSW is a clear sign of the times, but what lurks beneath will point to the long term. Whatever that means to the reader, I will wonder. But for me, a variety of NWP and teleconnections is the way to go. Linking the two, and asking the big questions about the effects on each other is what it's all about.
  13. Just following on from Tamara's great post above..... Frictional Torque is currently going into a negative trend. After a FT peak, then followed the current MT peak, that has sent the AAM to it's current position. Below is my thoughts, based on my observations and forecasts of the key drivers. The FT will continue to decline into the negatives, and bring the AAM into a negative trend, towards a GWO Phase 7 & 8. But the question is will the MT make a full decline as well? Yes, you could try and use NWP to try and work out whether the EAMT will take a dive, or what will the Rockies MT do? These are the questions that need to be asked. I am referring to the massive +EAMT, and the currently -RMT. Despite the sudden MT dive in the Rockies, the EAMT has been driving the Worldwide MT to levels that are quite literally off the charts. It is this, that has caused this AAM progression, that nobody forecasted and seems to defy the Niña base state. Whether this is an indicator of Niña weakening, or just a minor hiccup, isn't my question to answer, but many experts have been questioning the dominance of a Niña base state. Anyway, this is my 'forecast'(yellow line), with annotations included. This assumes that the MT has a large negative trend, maybe it doesn't, and acts like a Niño GWO cycle. But I personally doubt this will happen, IMO that shouldn't happen so suddenly. It's one thing to have a +AAM, and another to have a Niño like GWO cycle. Anyway interesting times ahead, let's keep watch for the next steps of the AAM's progression.
  14. Yes, Phases 6-7 tend to be the best for SSWs, so part of the forecast SSW involves that. I don't believe it will have much of an effect on the MJO weakening into P8 however.
  15. I know these have already been posted, but bigger picture EC46 Day 20-25 Day 25-30 Day 30-35 Day 35-40 Day 40-45 Full NAO forecast from the EC46.