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Overall there is little I would change from any of those excerpts from the previous post. First the matter of the programmed Atlantic ridge as explained and discussed in previous post and now well within the modelling radar. It remains the case that the cool air Atlantic ridge sequence is a snapshot in time set against what has been and what is still likely to resume thereafter. It has to be said though, those of us wishing for a summer bank holiday to reflect the stunning overall quality of the season - that the weather looks set to certainly not read that particular script and the timing is quite unerring indeed. It is looking increasingly likely that the upcoming Bank Holiday, at least for many southern and south eastern parts who have been fortunate to see the best of conditions, will be the most underwhelming for a few years, Last year featured a fast track to early autumn conditions both prior to and immediately after the Bank Holiday, however the whole holiday weekend period itself was very warm and sunny for many at least further south, echoing that of 2016 and also 2015 which were both fitting for the end of season. Some enjoyable mid level plume conditions and evening lightning displays also added an extra element in 2015, and 2016 went on to feature these conditions well into September itself Another way of measuring related analysis to the programmed Atlantic ridge sequence, is the short term tropical convection VP plots that identify the loss of signal and meandering track to the Maritimes and emerging there by the closing days of the month. This is sufficient, in the shorter term, to be amplifying the upstream Pacific pattern and also pull the ridging pattern westward downstream and invite cool air advection from the NW. Much as described in the last post. However, the emergence of the tropical signal from the Maritimes (and then subsequent track back eastward into the Pacific) is what is a key to reduced trade winds serving to de-amplify the upstream pattern once more and help return to warmer and hopefully also more settled conditions downstream in our sector with time This links on to the updated zonal wind analysis below used as focus for those who wish to welcome in autumnal type weather and which reflects the interim short term loss of tropical forcing in addition to transitional CCKW across the tropical Atlantic (which was covered in last post). I think the particular point has been made before that taking these wind anomalies plots in isolation of the broader picture associated with it tells one part of the story but not the complete picture As hinted at above, it also means that any autumnal flavour to the weather is quite likely a temporary feature with further summer-like weather delaying the eventual seasonal changes that happened faster last year. This doesn't 100% guarantee any heatwave, though still plenty of time for one to develop in the new month, and still plenty good enough to continue to enjoy outdoor life for a while yet despite the B/H spoiling things for quite a few. The bigger picture, beyond the short term analysis, remains one of trying to assess the present lull phase in the tropical cycle and associated increase in trades against a larger atmospheric/ocean trend that has been heading in the opposite direction to any La Nina type forcing through the latter part of this summer. Albeit, with erratic progress which is now proving perhaps a little slower and more frustrating than seemed to be the case (hence the window for end of official summer plume that seemed possible in the last week of August has been put back a bit as just discussed) Its worth reading the attached link which discusses the role of the South Pacific Oscillation (SPO) in regulating the strength and influence of easterly trade winds (to which the immediate post under reply reflects with the short term zonal wind anomaly forecasts) The link was provided originally kindly courtesy of @Blessed Weather https://www.climate.gov/news-features/blogs/enso/look-south-enso-forecasters A +ve phase SPO suggests a weaker South Pacific subtropical ridge and weaker trade winds reducing the cold-water upwelling in the eastern Equatorial Pacific and allows for easier propagation of the warm waters from the Central Pacific to the Eastern Pacific. This is consistent with speeding up the development of an El Nino circulation and associated high angular momentum regime. However the converse holds true with a -ve phase SPO and this means that propagation of the warmer waters from the CP to the EP are slowed and retarded. This is reflected in on-going ENSO zone profiles. It doesn't automatically mean that an El Nino won't develop at all - it just makes it likely to be slower to develop in this instance and also much higher margins to be on the weak end of the spectrum and more centrally based. This summer the SPO has been in slightly -ve phase and this has been a factor in the erratic progress of the development of the Nino standing wave as just mentioned. The relevance of a -ve SPO to this thread and the synoptic upstream and downstream pattern is that the relationship that the atmospheric circulation acquires to the ocean base state is one that features a more amplified Pacific pattern with stronger sub tropical ridging in the Pacific when the tropical>extra tropical set-up allows it. Stronger sub tropical ridging in the Pacific in turn regulates the development and orientation of the Azores/Atlantic sub tropical ridging in our sector. When the trade wind effect is greater, -ve frictional torque around 30N (and associated falling atmospheric angular momentum tendency) creates the mechanism for amplification to occur upstream to retract the Azores ridge westwards and means that cooler incursions and trough influence from the NW is greater. As soon as the trade wind effect reduces, then the developing Nino standing wave Pacific pattern has chance to regain more influence as soon as tropical convection patterns create westerly wind bursts to de-amplify the Pacific pattern as AAM bottoms out and then rises back up - and in turn return the downstream ridge eastwards and reduce the influence of polar maritime airflow with the jet axis SW-NE rather than W-E or even NW-SE. Such a more "Nina-like" sequence with the jet pattern switching to a more looped southern track occurs later this week before the pattern attempts to return to the flatter more cyclonic Pacific pattern that allows greater downstream amplification of the Azores high in the UK/European sector rather than to our west. This is yet another further element to the GSDM diagnostic process. Knowing how the upstream pattern is affected by factors such as these is a help towards determining how jet flow and trough and blocking features may also behave further downstream. So how much is the developing Nino standing wave likely to be "destructively" affected by any interim trade wind anomaly? With a new CCKW presently passing though the Pacific, easterly inertia is likely to be mitigated in the short term and then developmental to resumed progress in the medium longer term Additionally to this, the presence of a further CCKW in the Pacific also adds weight to the expectation of that low frequency amplitude MJO wave to develop across the Pacific as part of an atmospheric response to this. Signs of this starting to happen are discussed above. Furthermore, the CCKW passing through the Pacific also supports development of "non low frequency" activity in the form of cyclones. The tropical modelling (up the page) is starting to reflect the following on upstream pattern change more clearly on a shortening time period and this helps start to increase confidence that NWP will carry the signal forward more consistently and with better continuity. Both types of tropical activity, low frequency and non low frequency, are conducive to supressing trade effects and replacing with westerly winds that add an Asian jet extension across the Pacific, de-amplifying the upstream pattern - and, downstream from this, reversing the ridge/trough pattern in the Atlantic and returning the jet northwards once more - that is, following the loop south over the short medium term. NWP has kept the signal stubbornly beyond day 10 in recent days, but cluster and ensemble data should start to read better developments and though next week may still take a few days to settle down beyond the cool and changeable holiday weekend - things still look reasonably set for more fine and warm summer-like weather to return at the turn of the month and heading into September Latest 0z ECM clusters and GEFS ensembles continue to reflect these much improving prospects by the end of the month. With all the above in mind, there is much to agree with this third highlighted post. I would question the first and second lines though. From my own point of view there is no need to be silenced by any NWP currently (or indeed at any other time for that matter) and as based on attempted forward looking assessment. The end of week and B/H has been well anticipated in recent days and continues to not require any further reaction beyond what it is. An autumnal interlude as a snapshot in time that is best put into perspective of what preceded it and also the longer range likely perspective of which your final sentence quite reasonably assumes Personal optimum preference would certainly prefer ridging setting up just to the E/NE to invite a quicker route to plume scenarios and southerly winds. Up till recently this seemed quite possible. Though cautionary reality now suggests initial position of ridging my be a little further west ridging into the UK and across mainland NW Europe as dictated by the Azores ridge. Which in itself is not an unwelcome prospect by any means

Hello There are lots of really good sources on Netweather. Have you checked out the Learners Area? Knocker posted on CCKW around three years ago, but there are a lot of threads in that section dedicated to learning. Otherwise, my personal favourite is the one set up last winter by @Bring Back1962-63 which is full of really informative stuff in the Forecast models section:

Here's the forecast based on the 12z GFS Rolling CET... Anomaly to 81-10 rolling avg (Daily Avg: Anomaly to 81-10 daily avg) 18.0C to the 20th... +1.2 (19.2: +2.5) 18.0C to the 21st... +1.2 (18.4: +2.0) 18.0C to the 22nd... +1.2 (18.0: +1.5) 17.8C to the 23rd... +1.1 (14.1: -2.0) 17.6C to the 24th... +0.9 (12.1: -4.0) 17.4C to the 25th... +0.7 (13.3: -2.5) 17.2C to the 26th... +0.6 (12.7: -3.0) 17.1C to the 27th... +0.5 (13.0: -2.4) 17.0C to the 28th... +0.4 (14.2: -0.9) 16.9C to the 29th... +0.4 (15.1: -0.2) A big cool down coming after mid week, with possibly the coolest August temperatures since 2014. At this stage, it's even possible that we end up below the 81-10 average after corrections! Who'd have guessed that 3 weeks ago!?

Thankfully the UKMO seems to have lost it's bank holiday ruining low. Now has a small area of high pressure at T144: GEM and GFS also seem to have this feature nosing in from the west, bank holiday weekend rescuer! Its transitory but the main ridge then follows, both looking good at T240: Some consistency seems evident in the models today, even out to day 10. Edit: GFS at T360, and the heats back proper

Not necessarily, as it depends on where the cold air is being sourced from. Given some of the unprecedented temperature anomalies we've seen over the Arctic in recent years then perhaps cold spells from direct northerlies will be far less potent than they used to be, in which case "0.8°C less severe" may be an underestimate. However, we have seen some truly brutal cold-pooling over Siberia in recent years, which many believe could be a consequence of a warm Arctic (often referred to as "warm Arctic, cold continents"). So it may in fact be the case that we see Siberian-sourced cold spells increase in severity. The remarkably cold weather we witnessed in late February and early March of this year (upper-air temperatures briefly touching -17°C; you'd probably have to go back to 1987 to beat that!) perhaps demonstrates this. And what of cold sea-surface temperatures in the north Atlantic due to a weakening AMOC? If we see cooling in the right regions then maybe this could, to an extent, negate the effects of warmer Arctic air because the water over which the air is travelling becomes colder and hence we see less modulation? The same goes for cold-and-snow events off the back of Winter depressions: perhaps marginal events see more snow whereas previously we may have just had cold rain?

Essentially this week is a week of two halves as towards the end of the week the surging sub tropical high veers the upper flow, including the jet, north westerly in the eastern Atlantic which drops a cold trough over the UK replacing the warmer and humid air that had prevailed in many areas of late. As noted by last evening’s EPS So today sees much of the UK in the humid and warm air, with Just N. Scotland escaping, resulting in a fairly cloudy day for many, particularly in western areas where St and mist may be an issue, but the cloud may tend to break up during the day and where it does it could again get quite warm. Possibly some light showers sneaking into western areas during the afternoon that will fizzle out by evening. Overnight and through Tuesday much the same picture for England and Wales but the next wave and associated fronts tracks north east during the day bringing rain and windy conditions to N. Ireland and western Scotland by the afternoon. Again temp rather dependent on cloud cover. Overnight Tuesday and through Wednesday the low continues to deepen and track NNE whilst the cold front and band of rain moves slowly south east across the country leaving much cooler conditions in it's wake. South of the front, particularly in the south east, another quite warm day. By Thursday the upper air analysis illustrates pretty well the opening comments with the trough sinking down over the UK On the surface the cold front has cleared to the south leaving the UK in a cool, unstable and fresh north westerly airstream resulting in sunshine and frequent showers and with temps appreciable lower than of late and below average. A very similar story on Friday in what is essentially quite a chilly day, especially relative to this summer. And the not unexpected NH profile at T120

Thoughts turn to the week following the Bank Holiday weekend, and signs from both the ECM and FV3 that the horrendous GEM / UKMO outcome was the result of some hideous computer glitch. ECM first and at T240 has a rather odd arrow shaped high pressure, no doubt where it's pointing so that's all good! FV3 which has supported the ridge scenarios into September for some runs now, has this at T216: On today's runs, all of them, I'm 70/30 in favour of a significant early September heatwave now Edit: Yeah, go the FV3 ?️ T252:

Well, it's certainly reinforced by the ECM mean at T240: This system will be slow moving giving prediction at day 10 possible. But every model is showing it. Here's the FV3 my current favourite model 12z, Here at T240 and T 360: What interests me is that this resembles the situation in the middle of June, that is a recurring pattern, I think this could start a significant warm dry period from start September.

Can you ask it what the score will be in the Palace v Liverpool game?

Got home after a round trip to a pretty comfortable Cirencester to a very uncomfortable humid Sheffield,the difference is marked. Humidity is by far the most uncomfortable weather in the UK for me,it brings nothing,just sweat and dehydration,pointless crap which hopefully will be gone by the weekend. Can't wait.

Thanks again, Tamara. One thing - can anyone point me towards a quick-look glossary of the various acronyms used in the posts talikng about teconnections? For example, CCKW.. not a clue what it stands for or what it means? Just a decode of the acronym and a brief outline of what it is will do me. I can then read further if I want.

But dark nights equate to lamp-post watching!

I’ve just popped over to the mod thread, it’s scary to hear them talking about the weather turning autumnal. It doesn’t seem like it was that long ago we had snow. The summer seems to have flown by that I feel like we haven’t even had one even though it has been a unusually hot one. The nights are drawing in, the kids holidays are nearly over. What is going on????

One of the best locations in Katchberg is the Pritz Hutt in the nearby pristine Gontal Valley. No cars , horses and walkers only about 45 min brisk hike from the village centre. Simple mountain fodder and good ale. Andi the horseman plays all sorts of tradition music there and elsewhere in the village. Great spot this. C

Haven't checked the clusters for a few runs, here's what they say for the 28th Aug and then about a week later, 2nd Sept 28th Now 2nd Sept So general overview - next week starting with north/south split, but good weather spreading to all by the first weekend of September, with small chance of a warm euro low affecting the SE

The partial moon looks beautiful tonight, low in the sky and orangey coloured. I would echo the sentiments about what a lovely day it has been. We walked along the river to Kingston and it was perfect sunny conditions with a light warm breeze; this evening was so pleasant after the gym at 8.30 that we took the dog out for a nice long walk at sunset - it was so warm it took him an hour to cool down bless him (that's frenchies for you).

Looking at the extended GEFS 12z mean there is currently a very strong signal for high pressure domination and depending on where the high is positioned, there is potentially a very warm end of aug / early sept...judging by the postage stamps there are some warm / very warm and even a few hot ones..also some cool / average ones but anticyclonic could be where we are heading.☺

Because it's true, and you can confirm this by looking at historical weather data - no offence intended but nearly everything you post is based on what you feel rather than anything certifiable. As an example, 22 of the past 30 days at Linton on Ouse have had average humidity levels greater than 70%. Last July, 25 out of 31 days had average humidity levels above 70%, 19 above 75%, 11 above 80%, and July 2017 was just an average month. Indeed, it is during summer heatwaves that humidity levels tend to be at their lowest, with dry air being more conductive to high temperatures.

Tonight's Ecm 12z ensemble mean looks really good longer term..As did the operational with the azores high gradually building in..a summery early september if this is right!☺

Most Summer days are humid....really? I think you'll find they aren't! Being surrounded by water doesn't mean constant humidity in summer. Very very surprised you came out with that one,no idea why you'd think that,very strange.

ECM take on things, first T144: Again that small ridge just doing enough not to totally ruin the bank holiday weekend. And at T240: So we now have multi-model agreement on the ridge of high pressure at the 10 day timescale, the settled warm, in some places hot start to September now more or less guaranteed in my view.

The sun did break through today, briefly. Enough though, for a family meal outside, which went well - well sort of. Cloudy mostly but, temp 17- 18C. I am in disgrace now, sitting in the kitchen alone, punishment for disrupting the party, as one member of the get-together is a UKIPPER and Trump supporter - god help him.

This was flying out of Barcelona last night. Possibly the same storm. VID-20180820-WA0002.3gp

17.9 to the 19th 1.9 above the 61 to 90 average 1.1 above the 81 to 10 average __________________________________ Current high this month 19.9 to the 6th Current low this month 17.7 to the 1st

That looks much better - none of the watery height rises we’ve seen forecast, something much more substantial perhaps as we head into September. Could be very nice and mellow!

It's 18C, it's damp, it's breezy, where the cloud breaks the people under it are lucky. Not great really...

Was a beautiful evening in our part of the world last night - the breeze and the clear skies was a real Costa del Cobham evening !!

August started well here, and will probably finish at least slightly above average temperature wise. However it has been rather cloudy, 76 hours on my station (probably a slight underestimate but still not good). The Met Office had sunny symbols yesterday afternoon but instead the cloud thickened here while breaking up for Dorset/Somerset eastwards. 0.1 hours of sun this weekend which makes it 3 out of 4 cloudy or wet weekends. Anyway, I thought I'd plot my maxima so far this summer against a crude average line: (just made a smoothed line graph using the monthly average maxima for Exeter Airport and subtracted the average difference between there and me) Quite impressive how many days are above average. The May-July period was probably one of the best. However I think one could argue that August doesn't look quite good enough for summer to be one of the all time classics, as it's one of the two warmest months on average and when most people holiday.

Summers in order with the best at the top 1976 3011995 2982018 281 (up to 19th August)1983 2781955 2771911 2741984 2711959 2691975 2681949 2671989 2621947 2551933 251

Up really early again, to escape the muggy air in the bedroom, despite our fan being on full blast. It's no wonder looking at the current dew points. Nigh on 16c, in the area. Really can't wait for the forecast fresher air to reach us, at the end of the week!! Hope the forecasts don't backtrack, on that. Roll on Autumn, as far as I'm concerned. Going to sit under a fan and do some more work, on my "Fantasy" Competitions. Regards, Tom.

For most of us looking to enjoy the bank holiday, you can stick the 16-18c where the sun doesn't shine! Which of couse, it won't.

Bit of a weird spell at the moment, humid but not particularly summery. Looking forward to the much fresher blast next week to mix things up a bit.

got the garden ready for winter, beast from the east should be with us soon,

According to the Ecm 12z next Friday will be the coolest day nationwide, quite a shock to the system for those southern areas which earlier in the week look fine, very warm and humid..into next weekend, cool at first then gradually warmer by sunday and more especially BH monday further south and also signs that high pressure starting to build in from the SW during the last week of August and warming up too but trouble brewing to the north by T+240.

Yes Karl, it's like a dog with a bone, and not at all without ensemble support now either, here the GEFS mean at T276: Long range stuff and Met Office outlooks support this, so I'm still quietly confident of an anticyclonic start to September. Plenty of time for cold weather from November!

Comparison of the 12s at T144, UKMO, GEM and GFS: UKMO and GEM awful start to the holiday weekend. Can't say much more about UKMO as that's as far as it goes, but GEM holds the trough over UK for ages - utter dross - but maybe showing signs of change only at the end of the run T240: GFS on the other hand follows 6z and parallel, bringing a ridge in at same time: Nice And the September heatwave is still on the cards, T384:

Charts to warm the cockles of a coldies heart from the ukmo 00z!

If I could bottle up today, and release it every day from June 1st until Sept 30th I would. Perfect summer day, sunny, warm, some wind in the hair, and no extremes!!

I think some of you are getting just a tad ahead of yourselves. Even disregarding the fact that August isn't over yet, there is the entire month of September to go through and it was in September 2 years ago that temperatures reached the mid 30s in parts of England.. as the saying goes, don't count your chickens before they hatch. September is generally a pleasant, settled month so expecting autumn to suddenly arrive all guns blazing is perhaps setting yourself up for disappointment. It's like spring lovers expecting March to suddenly usher in warm, sunny weather even though March is still a cold, cloudy month and snow is still likely. Don't worry though, you have October, November, December, January, February and March to enjoy. That's the good thing about being a heat hater in the UK/Ireland - you have several months of guaranteed no hot weather. Us heat lovers can't even rely on a few hot days a year normally!

They can be misleading if you are using them in terms of how good a summer is but not in absolute terms. They are not been used to measure how good a summer is, it is just a simple case that if say it is 45mm on 30th August then we get a 31st August ex Charley event, and it increases to 88mm for the summer, it isn't going to be the driest summer on record, as simple that.

It's not that difficult to grasp we all like different things...Is It?

Obviously he has nout better to do then troll a weather forum on a Friday night. What a sad, and worthless existence. Hope everyone enjoyed tonight's storms. I'll compile my footage at some point and upload here. Night all

Little taster just from my phone from tonight's incredible display!

London is circled by cells!

not sure if this is a weather or sex report

Two shots I got with my phone as the cell moved out of Brighton

a few flashes and a big crack. then after watching my wife get out of the shower, we've had thunder and lightning here as well!

Love how everyone thinks they should be getting hammered by a storm already. People need to be more like