Duane S.

It does now very much look like there will be a proper reversal up above. One would imagine that would not be without consequence going through March, giving a cold March. An increased probability of anyway. But after this winter

Finally a pull back of the AH westwards is now trending later in the month. Any WAA in a NW /N / NE direction has been shown to be futile if southern heights and going to get filled back in. Taking into account the background signals, which back up the above, there seems very little doubt that the final winter shot (or, window of opportunity) IS incoming for around the last week of the month and into March…

I must say I do find it a tad strange that we aren’t getting a few more outlandish super low 850s ensemble members in far FI. I’ve been critical of the continual ‘Iberian heights’ talk by some on here but yeah they do seem super stubborn this winter. I think that whilst CC has no doubt played its part, right now it’s probably the ENSO state that is main driver of it. When you take the below strat signature into account + activity in the Pacific , I can’t help but think, surely, we will end up with a cold spell in the not too distant future. But in what has been the most frustrating winter I can remember, quite possibly not!

Cheshire Freeze Yep, we’ve got all the hallmarks of a cold March incoming

‘Iberian High’ removal looks a safe bet now… (has looked for a while TBF) This is at the extreme end but isn’t without support in the ENS. A very unusual chart and will send much delight to the snow starved Alps…

As has been showing up more and more in the past few days, heights are definitely trending to drop below us going through next week. The MJO influence starting to shine through on the output. Expect more and better of the same. Winter 23/24 chase #3 now well underway

A very positive day from a coldy’s POV. Eastern Pacific activity showing up is now on the charts downstream. Slow erosion of EU heights definitely trending. Even the Wedge option gaining some traction. Although, personally, I don’t think cold will arrive via this route.

Much better signs of a change in our favour, albeit possibly quite a slow transition, from second week of Feb onwards. Very difficult to pinpoint many (any?!) details at this stage though… The MJO dipole progression out of the Indian Ocean, through East Asia and into the Pacific was fairly rapid. It has continued motoring and has already powered through the western Pacific, where it will probably slow down. That quick-ish eastward propagation I assume was aided by the existing ENSO state. Although interference between the two tends to create a lot of noise and especially downstream in model output. Net result though, it is virtually into P7 at a decent (maybe surprising?) amplitude. Then perhaps… a slowly decaying El Niño may (just) prevent a more natural slide back into the COD later in the month, and the MJO even potentially progressing further to phase 8 Certainly not a prediction, just musings, but I think it will definitely be worth watching. A decent amplitude 7/8 for a period of time would (in all probability) greatly improve our late winter prospects. Longer term output… Original post: https://community.netweather.tv/topic/99814-model-output-discussion-22nd-jan-2024-onwards/?do=findComment&comment=5025525

@joggs It had a ‘91 feel about it to me. In no way would I predict we get what followed that though

Much better signs of a change in our favour, albeit possibly quite a slow transition, from second week of Feb onwards. Very difficult to pinpoint many (any?!) details at this stage though… The MJO dipole progression out of the Indian Ocean, through East Asia and into the Pacific was fairly rapid. It has continued motoring and has already powered through the western Pacific, where it will probably slow down. That quick-ish eastward propagation I assume was aided by the existing ENSO state. Although interference between the two tends to create a lot of noise and especially downstream in model output. Net result though, it is virtually into P7 at a decent (maybe surprising?) amplitude. Then perhaps… a slowly decaying El Niño may (just) prevent a more natural slide back into the COD later in the month, and the MJO even potentially progressing further to phase 8 Certainly not a prediction, just musings, but I think it will definitely be worth watching. A decent amplitude 7/8 for a period of time would (in all probability) greatly improve our late winter prospects. Longer term output…

@TEITS 100% what I was thinking. The 06z has got an old school Easterly formation written all over it. I’m not so sure heights would naturally fill back in underneath us again a couple of days later on, as the 06z FI charts would simply have it. I’d happily bank that chart at D11 and take my chances thereafter. I think upstream forcings would be more in our favour at this point.

I agree with @Mike Poole, I'd say the bulgey Iberian high is more of a consequence than a driver in its own right, but... at the point of forming, it now becomes a driver. It is more than just semantics as well. It is probably just too simplistic to label xyz as a pure and simple driver. The feeback mechanisims involved within the atmosphere will have us going around all chasing our tails as we seek the chicken from the egg (or vica versa etc etc etc... ) . I tend to view it on a simple pretext that high pressure fills in as low pressures are created and driven around the globe. Not withstanding of course, the fact that low pressures can't exist without high pressures and and the continued redressing of equilibrium in the atmosphere.

It will change of course but thats incredible how the mean, over 6 days, steadfastly refuses to enter phase 8 ! Amplified P7 should (eventually) at least help our cause P6 at this stage of winter in this ENSO state is more of a wild card I’d say?

This needs addressing. Sorry but this is no more than attention seeking durge. That or a complete inability to understand complex nuances involved. Not what those exact nuances are, but that such layered complexities exist and what that means for the eventual 'weather on the ground' in the UK. I ask you... what exactly have you brought to the party?? Respect goes to all those trying to learn (which, let's face it, is all of us to one degree or another every winter). Using phrases like 'another major fail' 'background zealots' clearly harbours an agenda. This sort of dross should not be accepted as an argument, just because you are entitled to 'an opinion'. Today's societal clamour to show 'two-sideism' unfortunately gives some validity to this sort of agenda-driven rubbish. So, should we take note of the likes of @Catacol @Tamara (and there are others as well), who go to huge lengths to lay out their thinking and workings (with caveats or course) or... or do I listen to Captain Hindsight and Dr Schadenfreude afterwards? Hmmm, tough one that... The crux (always conveniently ignored) is that without potential in the first place, we will always get zip in the UK. The clever part is highlighting that potential (irrespective of the outcome). Cold spells cannot appear without potential but potenital does not mean it will occur

Consistency it is not (although, Op aside, an improvement though)

06z Op. Outlier or trendsetter?

Whether people like it or not, the next chase has been signed off, and is about to get underway. Feb ought to produce another cold spell. When/where/for how long (and of course, still 'if') TBD P1 definately over progressive on bringing in the cold I'd say (we will probably need that secondary bout of WAA) but it is fine margins, the tipping point to early cold is definately clear and present. Some other great members are emerging and several other members that just missed this evolution.

Following on from the last thread... No doubt changes to the Hadley cell circulation through AGW has led to an expansion in the Azores High. However if the atmosphere is predisposed to retrogression / southerly tracking Jet stream, then it is irrelevant.

For once, my location is better placed than most for a possible snowfall on Wednesday. Yes, the chances are low but remain alive. Albeit the newly run Icon 18z still adamantly saying no, amongst most others today. GEFS very much keeping hopes alive and with blocking collapsing above us, for once, an 11th hour northerly nudge could still occur.. Not over yet. Probably. But not definitely

I'm going to go very simplistic here... I've been wondering these past few days, how much weighting there is in the models with regards to the MJO and Enso state. As in, MJO P6 + El Nino = (essentially) zonal. If they have much less weighting on the transportation / direction of heat flux (very favourable from what I can see) , then I wonder if we could expect a very abrupt flip in the mid - long range output in the coming days

History tells us getting excited 3 days out, when a model suite shows the tracking of a low like this one is optimal for your area, rarely plays out well . Still no trends north or south, just fluctuations within the wide envelope, model to model, run to run, are still in play. And no doubt will be for a while yet. For those on the south coast, I maintain this is our best chance of a channel runner landing in a long time. But, by like their very nature, the margin for error always involved (right down to T+0) will make it a low probability. So yes, the best in many many years, but a low Probability. It would be virtually impossible for it to be any other way. March 2013 I think it last was? When the Channel Islands snatched it away overnight! And let that sink in to some of the newer members on here. Overnight it shifted 80 odd miles south. High risk, high reward. Low risk, high reward rarely ever applies to the south coast receiving a decent snowfall. 10 days ago I said this low would be the big player, I also said it would likely fill and slip just south on a ESE trajectory. However, I didn’t foresee quite such a quick breakdown just a few days later back then, so I’m open to all possibilities ref. this low, including it tracking more north. Too far north will be to the likely detriment of us far southerners though. Often, in these situations, we have the comfort of if a system tracks too far south, the cold is at least prolonged. Yes that would apply but unfortunately only very temporarily, as a mid term warm up looks almost guaranteed now.

Ref the edging back north of the tracking of the system on Wednesday… Why oh why the surprise?? The 12z Icon and GFS Ops are still well within the envelope of eventual outcome. For the umpteenth time, it will carry on waxing and waning south/North from run to run for a while yet. It must be exhausting being some people on here

For once, being on the south coast could be the best place for snow next week. It’s extremely rare we get a channel runner that produces. Normally because the margin of error is in the low 10s of miles The ebbs and flows in the model runs, of the north/south extent of the PPN, will continue unabated for a few days yet, but it’s good to still be in with a shout of a few cm. What, I’ve discovered over the years, a lot of people in t’North really don’t realise quite how little snow we get down here. I’d happily take one day of falling snow giving a 5cm covering. Something which happens probably once every 7 odd years. Mid term, it certainly looks like we may have rolled a double 1 (when anything higher than a 3 would have given us a more prolonged cold spell to differing degrees). There could be improvements yet, but a relaxation in the cold for a good 7 days looks to now be the form horse. Longer term, well it’s only one driver, but its effect ought to be fairly influential moving out of Jan and into Feb. Half a month+ at high amplitude in the Pacific is likely to bring some goodies our way. Clearly this is subject to change as it heads through the Maritimes. Definitely one to watch though…

Well, there it is (very nearly at least). The mean has been edging that way for a few days now. Just into official SSW territory, could be the shortest one in history though

The models are struggling, everything is very much still on the table. ECs making much less of the ‘mild blip’ for the far south and keeping things very cool indeed in the UK tropics. GEFS? Hasn’t got a scooby…