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Silly jibes aside, the anticipated trend showing its hand a little this morning; a slowing down of the Atlantic trough, leaving the 'heat low' in place for longer to our south, so increasing the potential for the mega-plume to find its way in via France/Germany/Belgium. IF only we could avoid this! The anomaly charts, however much out of favour with with some are not often far from the upper air pattern in the 6-10 day range and better than most overall outputs from any synoptic model in the 8-14 day time scale. Again not a flip comment but based on many years of watching them daily and doing statistics a few years ago. Nothing since then disturbs my feeling they remain as reliable as then. 70-80% 6-10 days and approaching 70% 8-14. They do not give the surface pattern, nor do they show what can happen on a day or even two days out of those periods. They are mean charts. Currently they are predicting in the upper air what you see in the links below http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php This pattern has slowly evolved over a 3 day period starting about 4 days ago. The 8-14 is not too different from this http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html Not entirely in agreement especially the GFS which has oscillated between troughing as the main feature and ridging just about being the main player. Yesterday they seemed at variance with most synoptic models (not too unusual) and UK Met (0130 output) but I notice now that they (UK Met) are suggesting a more, albeit fairly light, westerly type flow. The charts I show would, to me, suggest no major heat even in the far SE apart from an occasional hot day as a surface high becomes resident over/near the UK. No major Atlantic onslaught either. Not sure how much rain away from more NW and at times W'ern areas as it does suggest a lot of dry weather to me. The occasional extension of more changeable weather SE as fronts work around ridging which quite often may be, at the surface, W/NW of the UK. What happens beyond 2 weeks is out of my ability to give sensible advice.

im guilty of committing the cardinal sin when viewing these charts.... making assumptions based on 1 run, when the basic rule for employing these is 'consistency'. besides that theres not much ridging on that chart, and theres a decent westerly upper flow. ill not hide away... i was wrong.

I’ve collected some statistics together. Some of the stuff here may have been mentioned by myself or others already, so apologies if you see any repeats. Some statistics for July 2018: A final figure of 19.1°C makes July 2018 the third hottest July on record and fourth hottest month on record. The lowest daily mean was 16.2°C on the 17th, which is the second highest of any month on the record, behind July 1783 whose lowest daily mean was 16.3°C. Joint highest with 1783 for the most July daily means above 16°C (31). Most July daily means above 17°C (29), beating 1783 (28). Second highest for the number of July daily means above 18°C (23), behind 1983 (25) and ahead of 1783, 2006, and 2013 (21). Joint-third highest with 1921 for the number of July daily means above 19°C (16), behind 1983 and 2006 (21), and above 1911 (15). Third highest for the number of July daily means above 20°C (11), behind 2006 (15) and 1983 (13), and above 1995 (10). (With two days above 22°C and an additional day over 21°C, the corresponding ranks for 21°C and 22°C are much lower.) In addition to all 31 days of July 2018, the last six days of June 2018* all recorded daily means above 16°C, which puts us on a 37-day streak of such days; this is joint with 17th July to 22nd August 1911 as the second-longest streak of this kind on record, behind only 1783, which managed 44 such days from 22nd June to 4th August. This record will probably fall. Some statistics for 2018: The June-July period is the joint-third hottest on record with 1826 (17.60°C), behind 2006 (17.80°C) and 1976 (17.85°C). The May-July period is the hottest on record (16.13°C). The April-July period is the hottest on record (14.55°C). Despite what was overall a cool March, the March-July period is the second hottest on record (12.62°C) just behind 2017 (12.72°C). * Apologies here. In a previous post I made an error and quoted seven days instead of six.

This may seem a bit knee jerk but I'm sensing, bit by bit, a move from a pattern that allows for long settled periods, to a pattern that only allows shorter ones. Next Wednesday may well be the end of the long, unbroken days on end of 30 degree heat? Most runs just seem more and more westerly after this time, and though I never buy Atlantic height rises in advance unless they are anomolously strong, heights do seem to want to hit the Atlantic rather than the UK. But then again maybe it'll just be a period of a few days. And of course the models were gunning for an unsettled spell mid July at one point, which completely did not happen. So perhaps early to be looking down this road. But if someone begged me for a forecast D7-D14, that's what I would say. Until then, the question is just how much heat we can get out of the present pattern! Still looking like the very hottest air will stay south, but we're still 24 hours away from being sure. Still time to dig that low further south before Tuesday, which could just nudge that record breaking plume of air that 200 miles further north - that's all - to transform the temps from low 90s to the high 90s.

@johnholmes sorry if I enraged you there, it was not intended as I was being silly - hence the use of the word - by referring to their charts from 2 days ago instead of today's ones, which have altered the orientation of the positive anomalies in a way that tones down the suggestion of mid-Atlantic ridging. The only thing that bugged me a couple of days ago was their level of confidence despite the uncertainty associated with background forcing - it would be respectful of that to set confidence at a 3, maybe 4 at a stretch. Moving on - interesting developments from the GFS 12z for next Monday compared to the preceding run (or indeed few runs): The trough is elongating more toward the Azores on the 12z run right) compared to 06z run (left). Granted, it doesn't reach anywhere near that region, but the fact it's reaching down further west than before is sufficient to allow more time for pressure to rise across Scandinavia Mon-Tue. On this particular run, the jet is a lot stronger due to the low having been flatter in shape during Sunday (a bit counter-intuitive if you ask me...), but that need not have been the case. With the same jet stream strength as the 06z, I believe the cool polar maritime air would have continued south for longer, passing west of Iberia and bringing about a stronger Iberian trough development than we've seen modelled lately. That's a hotter and more thundery outcome to watch out for. The UKMO 12z appears to have the weaker jet + trough digging further west combination I'm talking about. Much as the 00z run did, to the model's credit. Still time for further westward adjustments to where the trough digs south, but thundery spells are a fit to the Nino background in August, so I'd be surprised if we didn't see anything thundery for at least part of the UK after next Wednesday at the latest.

All models over the last 24 hours ( especially the ECM ) have repositioned that high slightly further East allowing more of a southerly index - Also, gradually similar to July any unsettled weather is being pushes back- Still expecting to see temps North of 35c in this hot spell with the record attempt still lurking in the 'potential' background...

I wonder how confident NOAA are in that anomaly plot from two days ago now... Silly jibes aside, the anticipated trend showing its hand a little this morning; a slowing down of the Atlantic trough, leaving the 'heat low' in place for longer to our south, so increasing the potential for the mega-plume to find its way in via France/Germany/Belgium. This outcome requires a more prolonged draw to threaten us with dangerous levels of heat, in contrast to a draw from the south which is quicker and more intense but tends to break down sooner anyway. The thing about next week though, as that we have a different direction of trend being encouraged by the teleconnections - last time it was toward a greater eastward push of the Atlantic trough due to the conclusion of the last tropical cycle, but this time it's toward a weaker push with the trough staying further west. At this stage it's impossible to be sure how far this might go, but that GFS 00z run comes very close to keeping it far enough west that the 'heat low' doesn't get a chance to escape NE until at least next weekend. In fact I think it would have got there had it not failed to bring another Atlantic trough into play with the Azores High being shoved NE again (still waiting for that next stage to be 'realsied' by the models). This potential might yet be taken down in a different way to the too-progressive Atlantic trough outcome though - that trough could instead dig down west of the UK a bit, with the 'heat low' moving right up through the UK on a near-northerly path. Another way to arrive at the quicker, more intense but shorter-lived result. The ECM 00z comes quite close to this outcome; it was just a little too progressive with the Atlantic trough. Given all the above possibilities, it's no wonder that the ensembles are well scattered at the moment. Still at least a couple more days until we have a good idea of what happens Monday onward, I reckon. Oh and - UKMO, forgot about that one! That's actually only a stronger ridge away from a gentler, more easterly variation of the trapped 'heat low' scenario. It would likely become hot for a number of days, but not dangerously so.

They key to any certainty is consistency - and when the ensembles split so much at only 5 days away like they are at the moment, you just can't forecast anything and be sure about it. We could still end up with anything from just warm weather to something exceptional (35c+) again just after the weekend. Loads to sort out! It's like being here in winter!

Slightly longer term but the models seem to be looking much more settled this morning. Gone is the U.K. trough on the GFS and Scandi low on the ECM. Maybe some were a little too quick to jump onto the unsettled bandwagon yesterday? Still a fair bit of ensemble scatter though, so still some uncertainty.

Over the next few days pretty much a NW/SE split with cloudier and cooler in the former and the reverse in the latter. The current NH profile A reasonably fine start to the day in many areas but still cloud and patchy rain around in the north west and western areas. This will develop into a fine day, with perhaps some variable cloud, in much of England and Wales and eastern Scotland but the next frontal system us swinging rapidly north east and cloud and rain and strengthening winds will reach N. Ireland by midday and spread to Scotland and the north of England through the afternoon and evening. The cloud and patchy rain, perhaps interspersed with some heavier bursts, will linger across the north west and through the night and Thursday will spread further south and east to encompass much of Wales and the west of England with the cloud even encroaching into the midlands, Throughout this the south east will get a tad warmer.albeit it's still relatively warm elsewhere. It's worth pausing here to take an overview oft he situation and we find a cut off upper low to the south west that has initiated some very warm advection from NW Africa into a Iberia and equally important still a lot of west > east energy from N. Canada, and from the sub tropical jet, thus a strong westerly upper flow over the UK So for the time being the north remains cloudy with patchy light rain but with high pressure becoming more influential in the south temps becoming hot in some areas. Saturday sees the influence of the high pressure spreading further north thus a sunny and warm day for most and hot again in the south. Sunday sees the upper low and trough in the Atlantic still pushing east but this serves to amplify the ridge over the UK and to advect the warmer air further north to the south west resulting temporarily to a shift west of the surface temps. There is a very fine balance here of the energy/amplification scenario and the future evolution so this is just according to the gfs. The NH profile at T120

Time to look at the jetstream profile forecasts I think... and these suggest a shortlived plume scenario over the weekend and into next week, a build of a ridge, but then low pressure taking over from the NW, thanks to a dig south in the jet, much like occurred just before last weekend, thereafter it stays southerly for a few days before backing more flat with the azores high perhaps ridging NE at times. It does appear there are increasing signals August might be far more typical than recent months, with the atlantic gaining the upper hand. August traditionally sees the jet ramp up a gear, and sustained settled conditions are less likely than in the April-July period. Not saying it will be a washout fest, just perhaps a more normal summer pattern which will still mean plenty of warm sunny dry weather at times, more so in the SE, with the NW most prone to more unsettled cool conditions.

Day 5 charts UKMO/GFS/GEM The GFS has a much deeper low compared to the other two and as such we do not see the high sheer off so a westerly flow for northern areas as opposed to the light continental flow seen on the other two. Day 6 Again the GFS and its deeper low does seems to want to push the trough cleanly eastwards and we see a fresher westerly develop during the middle of next week. The UKMO and GEM are starting to slow the eastward progress of that low down so not strong guidance as a developing cut off low that could form on either the GEM or UKMO could lead to a drastically different solution further down the line. The GEM parks the low over the UK but at that timeframe a similar evolution could lead to the low being further west which would allow a much warmer southerly flow to be maintained. Not overly convinced going forward apart from up to next Tuesday there looks like being a lot of fine and dry weather with temperatures above or well above average with hot conditions in the south at times.

Finished the Tour du Mont Blanc today. Great hiking, amazing scenery and wonderful weather though this evening there is thunder and rain in the air. I don’t mind though, after 10 days camping I’m in a hotel! Some photos from the last few days...

A great run from the ECM- there's a good chance this settled weather could continue for some time. This summer isn't over by a long shot! Plenty to be positive about with a cracking weekend to come too. Fine and warm weather is still the form horse.

That heat to the south dangles like a giant tease (Or giant guillotine depending on your preferences) but it seems the jetstream across the Atlantic looks too flat to pull the hottest air towards us, the ECM pretty much stalls the line of the hottest air in the same place for most of the run. Friday looking like the hottest day for now, again 32c (90F) looks like being breached. The low south of Greenland looks like it could begin to dig southwards this coming weekend but it seems to end up going straight east through any developing ridging with varied outcomes depending on the model you chose to look at. It still looks pretty fine and warm until possibly the middle of next week with 30C reached possibly on every day from Thursday onwards to day 10 depending on your model output of choice.

Apologies Moderators in advance! Where do I even get going with this one!? You're in Leeds yet you're lecturing people in the south east that they were moaning about nothing as it wasn't that hot...in Leeds! I don't remember most of us complaining when it was 25-28 degrees with 30% humidity - we moaned when it hit 34C with 45-50% humidity and, despite keeping curtains closed through the day and opening windows once it cooled-off got slightly less oppressive in the evening, we still had to try to get to sleep with the temperature between 28 and 30C even at midnight. I don't care if you discount the fact that most of us who were struggling have valid medical reasons for so doing (in my case medication that affects my ability to deal with heat); what I want to know is why you're so insistent on the south east hitting 35C/40C/whatever level you desire when you don't live there? I'm not being aggressive or sarcastic; I'm genuinely baffled. Secondly, I was told off for saying that heat-lovers were trying to enforce their preferences on the rest of us by repeatedly stating, in some Orwellian manner, that we all think the same way. I was informed that I was trying to impose my preference for not having heat exhaustion and feeling ill all the time cooler conditions with some rain on others, but, I'm sorry - claiming that a cool, wet August "would certainly benefit nobody" when farmers are desperate for more rain* and many of us here are dreading another heawave over the weekend and through next week is an attempt to persuade others by repeatedly stating something that is demonstrably not accurate. I'm sorry that I am weak and inferior and do not meet your standards for heat-tolerance; I suspect you could probably eat food so spicy that it would burn my digestive tract and you can probably leap tall buildings in a single bound, but please show a little consideration for those inferior beings such as myself! *Links: https://www.bbc.co.uk/news/business-45018746 https://www.theguardian.com/environment/2018/aug/01/uk-farmers-allowed-to-take-more-water-from-rivers-as-heatwave-continues

Hardly an "extreme possibility" when most of the other models and Met office have been singing from the 06z hymn sheet for a few days now!

Looks like the CET has been confirmed as 19.1C! A downward corrections from 19.30 to 19.13C. https://www.metoffice.gov.uk/hadobs/hadcet/cet_mean_2018 https://www.metoffice.gov.uk/hadobs/hadcet/mly_cet_mean_sort.txt

Just to clarify this Jeff An adiabatic process is one during which the temperature of an air parcel can only cool or warm through expansion or compression, respectively. As air parcels rise, they expand and therefore cool adiabatically; as air parcels sink, they compress, and therefore warm adiabatically. The DALR is the rate at which unsaturated [relative humidity < 100%] air parcels cool or warm and is a constant 9.8°C km- at any temperature or pressure level. The MALR is the rate at which saturated (RH= 100%) air parcels cool or warm, but unlike the DALR, it is not constant. When rising saturated parcels cool adiabatically, they release latent heat, which offsets some of the adiabatic cooling. Therefore the MALR is smaller than the DALR and its magnitude is dependent on temperature, because warmer saturated parcels release more latent heat. At warmer temperatures, the MALR is less steep than it is at colder temperatures indicating that as warmer saturated air parcels rise, they cool more slowly than colder saturated air parcels. In general, 6°C km- 1 can be thought of as an average MALR value, but the MALR is larger at colder temperatures and higher altitudes. In fact, if an air parcel is cold and/ or high enough, the MALR will nearly equal the DALR.

On Wetterzentrale, the max is 51C that day in Portugal! The previous record temp set there in 2003 was 47.4C for reference. The European record is 48.0C aswell. If that's accurate and taking into account GFS often underdoes temperatures, its going to blow the previous record out of the water. Its very dangerous heat too.

Think we should stick to the models in here. ICON 18z looks a move to the plume scenario at T120 (end of run) here with 12z at same time, 18z first:

Really devastating day now for anything left green on the farm with a gale force southerly wind at 27% RH and 18c.(The RH in the house is 62%) Neeps and grass wilting and dying back.Lots of apples and plums being dropped by the trees as drought bites harder today .You would wonder whether there was any rain at all in the last week . Don"t want to water anything as on well supply and needing it for personal use. Dust is blowing off tracks in great clouds. Only positive thing is spring barley is ripening faster than ever. Seeing and hearing of reports of pink straw in barley one theory being that the barley plant has died suddenly from drought trapping various nutrients in the stems creating the pink colour

A lot of responses/feedback about the diagnostic approach encompassing varying aspects of NWP analysis. Some misunderstandings and incorrect interpretations of the purpose of this approach continue to need clearing up - plus also some credit needs to be given for some of the very good efforts made to explain some aspects of the angular momentum budget 1) So to start with the credit first and foremost. That is to @Summerstorm@Mike Poole for their attempted analysis of the GSDM budget. It doesn't matter that some of the analysis would need some amendment because its hard to understand and my own understanding is still growing all the time, despite getting a useable grasp on the principles which is very rewarding from an enthusiast point of view.. The most important thing I think, is having a go at testing out new processes - making mistakes is the way to learn and no-one should be nit-picked for failing to accurately match the right solution to the pattern every time on day 1.000 let alone day 1. Its a tough audience at times on here, though the majority always seen to welcome these posts as much as the very good general NWP analysis from various many quarters on here. But the GSDM itself is highly complex and I struggle to convey the complexities sometimes to split the technicalities into simple English and would apologise for not always succeeding in this process.Its all well and good me understanding what I mean, but that doesn't automatically transfer to every reader. To this end, I would freely admit a mistake yesterday was attempting to explain links that I had access to but did not know at the time how to copy across to the post page. I'm not known as "technophobe Tamara" to a few who know me day to day for nothing! Anyway, *I think* I have resolved this thanks to a crash course on Windows 10 screenshots - and trusting that copyright of these is ok. A couple of the images and some re-attempted explanation relevant to current NWP will follow in this post 2) @Singularity refers often to the NWP reflections of Nino and Nina type forcing that I do myself (and his back-up on this is something I highly am grateful for) In context of this summer most every post has referred to these with reference to the expected synoptic patterns they represent. Reanalysis monthly and seasonal posts are also not my technical strong point, i.e condensing the succinct pattern that has been observed vs the expected one - but suffice to say my easiest answer is not the easiest and least time-taking to complete in practice. It is to read/re-read the continuity of the summaries since May, which are deliberately quite often re-copied (under self-reply) as a means to help continuity and understanding as well as to openly check progress of expectations. Its my own layperson way of re-analysis, and as someone who doesn't profess herself to be a pro forecaster - it works for me anyway 3) With all the above in mind, then it surely mitigates any charges of having ego and/or being condescending. I think if people are going to make such assertions then they should be made with sound justifiable basis. Positive criticism is not a bad thing, but its quite reasonable to have re-course to object to unfounded personal criticism. I regularly state there is no exam to pass or best forecaster competition on here - and at times the over competitiveness and endless countering of right vs wrong does spoil the gist and whole point of the thread. 4) The purpose of the GSDM analysis is not to replace or be better than, say, analysis of the upper air pattern via the NOAA maps. This is something that crops up sometimes both summer and winter. As just said above, there is no prize for best method or best "forecaster" who uses whichever method. But it is there as a diagnostic tool to help check the movements and likely future movement of the upper air pattern. After all, the GWO is a plot depiction of net global wind-flow - which is essentially a trace of the Jetstream itself. And as we know, placement of pressure patterns is dictated by the Jetstream ribbon. Knowing when the wind-flows are accelerating and decelerating, energy is likely to switch northwards or southwards (where and when) is surely a valuable assistance check to the upper air pattern and in turn a check on the accuracy of interpretation of NWP. It is simply impossible to explain the whole modelling concept of the diagnostics in one post, but it is possible to keep putting "live" analysis of the current state of play into practice and start building a picture. Hence the purpose of the continuity analysis as a means to try to do so 5) The purpose of the GSDM is to add substance to the upper air modelling on a macro scale basis. It is not intended to micro scale pinpoint temperature anomalies within the UK and precise conditions on the ground. However, it is not possible to get any idea of the micro scale details without accurate representation of the macro scale pattern first. Attempting to criticise the diagnostic element in this respect, as one such post has done since yesterday evening, rather completely misses the purpose if its objective. Its not mere teleconnections either - any diagnostic of the jet stream itself is more focussed than just anticipation of pressure placement according to various indices tools. 6) And so back to the present position itself and a further attempt to pit the background to the NWP As stated yesterday, total angular momentum has arrived at +1SD (standard deviation) above parity - representative of transfer of location of tropical convection forcing into the Pacific and help the changing ENSO base state and atmosphere couple together in reflection of a newly establishing El Nino standing wave. The cyclonic response as indicated by the depicted tropical convective anomalies in the Pacific are evidence of shift of the tropical signal to one that is characteristic of an establishing El Nino standing wave Transfer east of the tropical signal has the effect of changing the feedback of rossby wave dispersion which adjusts the longwave response to where amplification of the jet occurs further downstream. The importance of this synoptically is the appearance of the Atlantic trough/downstream ridge pattern of late which has been distinctly different to much of the earlier summer. An Atlantic ridge with pressure drop downstream is characteristic of a more La Nina like synoptic response - due to the longwave amplification occurring further upstream in the Pacific which has the effect of bolstering high pressure in the Pacific with a downstream high pressure response in the Atlantic The effect of pulling the Azores/Atlantic ridge westwards allows the polar jet to run across the top and down the eastern side of the downstream Atlantic high pressure. Clearly this is generally not an advocate for high summer temperatures usually - and encourages cool air advection to sink south This summer has been an anomalous exception to the rule. The low angular momentum conditions seen during mid June to early July resulted in the expected Atlantic/Azores ridge anomaly, but this has been unusually northward displaced and aided by the definitively +NAO tripole in the Atlantic, and kept the polar Jetstream much further north than would usually happen under -ve GLAAM conditions. This is not the thread for a thesis to look at causes of Summer 2018 heat, but there are various aspects of relevance here to take up from this Jetstream pattern analysis As also stated yesterday, tropical forcing has now subsequently lost amplitude in the Pacific and the result of this is to weaken the downstream amplification response and aid influence of the trough in the last few days. Atmospheric angular momentum as a consequence starts to fall from its peak. The GWO in relfection of this moves from the +AAM phase 5 towards what is called a "transitional" phase 8. What this means essentially is that the pattern is re-amplifying upstream as the momentum associated with the Pacific forcing wanes and easterly trade winds start to increase. The blue shading on the zonal wind anomaly cross section indicates the uptic responsek in -ve easterly wind wind-flow. Where wind-flows change from the westerly wind bursts associated with tropical forcing to the re-establishing of greater easterly trades (however temporary) - a torque is created by the turning force of the conflicting wind-flows. This is essentially represented by change of trajectory and speed of the jet stream and comprises a frictional torque. Greater net easterly winds at this location at the expense of tropical convection westerlies creates a -ve frictional torque and is the signal for relative angular momentum to start falling back. The manifestation of the rossby wave signature of this eddy created in the Jetstream is the new site for amplification of the pattern. The greater amount of easterlies added at the expense of westerlies, the larger the fall in angular momentum and the greater the upstream amplification and downstream response. This fall-back phase in AAM is registered in various monthly seasonal suites - it is model interpretation sensitive to the tropical pattern and its depiction of thr rises and falls of angular momentum accords to how the model perceives the tropical pattern unfolding. The CFS gets criticism for its modelling, but in term of seasonal atmospheric trends it proves a worthy assist to guidance and should be trusted I think much more than its NWP interpretations of pattern evolution. Clearly, the trend is not for much downside to angular momentum which endorses the background detail attempted yesterday to suggest that any amount of retrogression of the pattern in the further outlook should be taken with caution. More to the point, sustainably. @Man With Beard cluster analysis is a good illustration to me of recent suggestions I made that interirm solutions are not necessarily end games and also why I continued to recommend taking output, including the NOAA representation of NWP with equal caution. I trust its understood that is not to denigrate the NOAA upper air assessment - but simply that precise placements of features are especially critical looking ahead as to how surface conditions on the micro scale detail play out. Attempting such detail at any distance is prone to error any time - but especially at the moment. As far as I am concerned the macro scale outlook has not changed and it seems to me that incrementally the modelling is correcting westward positioning of the pattern in the shorter-medium term and better modelling the cut-off low feature that helps determine advection of heat in the weekend and into early next week period. However, beyond this and more particularly the extended period, some of the modelling (including clustering) looks dubious to me, especially how long any retrogressive lower angular momentum element manifests itself - and its best a wait and see is adopted and for now at least, not take each and every operational and ensemble suite at face value

For the record, July in the East: - 2nd warmest July on record [1910] - Joint 2nd warmest MONTH on record [1910] - 8th driest July on record [1910] - THE sunniest July on record [1929] - 2nd sunniest MONTH on record [1929] - also looks like the 2nd driest June-July period on record (1976 was 3rd) With thanks to Dan Holley: https://twitter.com/danholley_/status/1024729741859987456

It's not UV but a specific wavelength of blue light (if I remember correctly its 450nm). I've got a pukka SAD lamp but will have to bring it out as soon as the nights really begin to draw in.

I wouldn’t expect that at all - nothing suggesting a low pressure onslaught. Maybe lower pressure, but no washout at all. Just back to something more like average.

Many thanks for this post, really interesting figures. What has impressed me the most is the amount of times 1783 has appeared over last week or so for the continuous heat!. Thanks again.

The last few days of July 2018 have tarnished this month. It ended up not being that dry. Overall figures for England and Wales suggest that it may be just a little drier than July 2016, believe it or not. My impression is that the second of half of July hasn't been that special around here. This is borne out by the Manchester Summer Index plateauing since mid July.

Yep can’t wait until I have to start paying for my central heating again! ,

Looking at the GEFS 6z mean, the next week or so indicates predominantly very warm / hot weather across most of england and wales, especially further s / se with plenty of dry and sunny weather but an increasing risk of the high temperatures sparking some heavy showers / thunderstorms later. Beyond that there is a less warm trend as winds become w / nw'ly with temperatures returning closer to average but of course that range can easily change and the reliable timeframe shows plenty of heat for the s / se.

There's some absolutely scorching weather on the Gfs 6z operational during the next week or so (reliable / semi-reliable timeframe) especially further s / se where temperatures get above 32c 90f at times..

Morning all. On that point, yep there is a need for looking at multiple runs to get consistency to a degree, but the latest runs are always the most likely to be nearer the outcome for a given timeframe, unless less acurate/sparser data is fed in. Gfs op looking great if you like heat - on and off theres been a cut off low forming that then sits out to the west in bob/biscay - notoriousely difficult for models to handle, but currently this looks to keep the heat incoming at the backend of next week on the 06z. To get a hot thundery august would propell summer 2018 to the top spot for me personaly! I think the potential is there, and models are starting to favour a better fight between atlantic and continental heat.. Samos

ECM shows another short burst of heat towards the far south mid next week Settled and slightly fresher temps then follow with no sign of a major change away from the settled conditions yet

We all do that, mushy...If I want to use a chart, in order to clarify what I'm on about, I always opt for the one that expresses my thoughts most succinctly, and I think it might be a form of confirmation bias? Consciously or otherwise, we all have it, IMO?

Completely agree, I've been saying this for days now and a couple of people jumped on me for saying it. Dry and settled weather is still the form horse, and there is increasing consensus for this hot spell among the op runs this morning- I wouldn't be surprised if Wednesday ends up hot for most of the UK as well- we often tend to eek out another hot day in these plume type scenarios to what is originally modelled. ECM looking great throughout- a bit cooler after midweek but the Azores high seemingly keen to build in afterwards again. This summer is a long way from over. Write off Summer 2018 at your peril.

Thanks for this .Drought Summit being held in London today Wednesday the 1st of August between all the farm unions and Mr Gove today as most livestock farmers in the UK only have two thirds of their winter feeding requirements made so far this summer, lots of animals are being sent to slaughter early to reduce pressure on this feed which is already being fed in some fields as grass stops growing. We are supplementing too. Not only this vegetables as well will be short this autumn as irrigation supplies are exhausted. At the risk of repeating myself food supplies l will top politicians agendas this autumn not Brexit as large parts of the Northern Hemispheres food growing areas are suffering drought.

All main models this morning are more keen to bring the 16C uppers line to the UK by Tuesday, with the ECM nearly getting the 20C line to the Kent coast by the end of the day. This would probably mean surface temps well into the 90Fs. However, still a lot of volatility in the models for that timeframe.

@Northernlights i genuinely wish I could say anything of comfort, this is genuinely off the grid as far as normal weather regimes are concerned. I like to think of Scotland's most well know singularity ( so named after Buchan singularties ) as being in May. in 70% of years, this singularity repeats, an HP cell between 15th and 29th May each year. Except this year it maintained! Incredible synoptics and HP in the offing to re-establish after this week, that plus atlantic SSTa and Solar Min. Watch out for Sea Ice stories over the next few months too..

There's a lot to like about the Ecm 12z for those of us who want more very warm / hot largely settled weather with high pressure / strong ridging in control..southern areas look like seeing hot temps in the high 20's to low 30's c again during the coming days.

Just a quick comment re various folk using differing time scales. I'm guilty at times of not being specific enough, but can allthose,even when showing charts, at some point in their post tell everyone what time scale they are dealing with. Out to T+96 144 240 or whatever Or days 1-5 or 6-14 1 month ahead or whatever. Not sure this will find favour but it might help some of the newer folk trying to get to grips with different models quoted if something along these lines was used. Otherwise the output I read is fascinating and from the majority of folk with no professional qualifications in meteorology. Generally a joy to read apart from the odd jibe and dig by some others. thank you all for your inputs. I struggle with some of what is posted but, when I get time, try to read up and learn a bit more.

Rather late in the year for these little fellas

You were only saying what it showed. Fair play! I don't think there'd be any discussion on here for the current D6-D10 if we needed consistency before posting

August is when I get my first Autumn/Winter 'pang' - usually due to the subtle change in light level/angle of the sun. Wonder what date it will be this year.

Pub run also heading for the plume, T144: Maybe heading for similar to the 12z FV3, I think the models are starting to smell the sugar free Red Bull!

Good question, it’s based on the lectures and book content I attended and studied at university, and relates to the data assimilation process. There are times, though, when the models propagate a new tropical signal too fast, leading to those ‘jumping then gun’ moments. Interesting ECM 12z - much more in line with recent GFS output out to early next week, then sort of like the GFS 06z except for a lot of unconvincing vagueness - looks like a model in the process of adjusting to corrected forcing patterns...

So often the orientation of the high cell is key to temp variance

Slightly further afield... has the heat in Iberia broken the ARPEGE's scale over Portugal?

Another observation is that with the very dry air visibility is outstanding with the hills across the Firth showing up in great detail.This is unusual at this time of year when everything is usually much more hazy in the distance.

Lovely morning at Rosemarkie on the Black Isle as the last stop of our holiday before we head home tomorrow. Wife wanted to stop off to see her favourite animal, no not @Hairy Celt, but the dolphins, at Channory, who will hopefully put in an appearance in an almost flat calm sea. Last few days over west in Morven were a bit more unsettled, with us actually getting wet one day. Really though, getting rained on only once during a week in NW Scotland even in July, isn't too bad.

Much cooler today .Got a good nights sleep last night. A few photos from the last week. Currently light rain and 13c Last of hay baled into round bales last Tuesday in warm very dry conditions. Taking in bales in the evening. Photo of last sown almost ripe spring barley today only just at the end of July. 2018 is certainly an amazing year weatherwise.