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The ECM difference you illustrate as measured by the Global Wind Oscillation in reality being in "transitional" Phase 8 as of yesterday 14 August.... .....rather than heading through low angular momentum La Nina Phases 1 into 2, (as suggested at face value by those operational outputs a week out) which models a sharper Atlantic ridge and hence greater cool air advection from the NW than has been the reality The reasoning as so often discussed in these posts being the degree of upstream amplification in the Pacific which serves to retrogress the high that is downstream from this in the Atlantic - and with the polar jet pulling troughs around the top of the high c/o of a more NW/SE axis. If the model overcooks the upstream amplification, then it overcooks the polar flow and looped jet axis Looking at the Pacific we see an increase in trade winds (covered in last post) following the passage of westerly winds c/o tropical activity which is now in end/re-start cycle - simply a natural pause in the tropical cycle and coinciding with CCKW towards the Western Hemisphere. Its this that modelling is jumping on and gunning for as pattern evolution to Atlantic ridge. This actually mirrors the sequence during the first half of July - the difference being that the trade wind increase is set to be weaker this time (albeit seasonal wavelength changes since then mean that the polar Jetstream is rather naturally adjusted further south according to this latest global wind-flow position than earlier summer). Notwithstanding that, the significance of the trade wind increase being weaker compared to back then is that in related terms, global atmospheric angular momentum is significantly higher than it was in early-mid July - - so extrapolating an establishing mid Atlantic ridge ahead on this basis needs some care and caution and none of the usual MOD discussion premature declarations in terms of an early autumn (beyond a possible transitory cooler interlude) This isn't 'teleconnections' saying "No" to an Atlantic ridge either - its an attempted diagnosis as to how likely a wind-flow pattern is to assist it developing and lasting for any meaningful time. Compare current AAM establishing closer to parity to the more -ve longer term establishing pattern of August/September last year c/o the persistent easterly trades and La Nina standing wave. N.B Its seasonal wavelength changes that are the essential importance here which heighten the Atlantic ridge synoptic response to -ve AAM conditions from mid summer increasingly into autumn This on the other hand looks very much like a transitory phase and certainly not a shift regime phase such as was seen during late July and August 2017 where a persistent signal for a mid Atlantic ridge in late summer and early autumn was well supported. The summaries since May have been covering this aspect and fully anticipating it and stressed the differential as to mid summer crossroads *should* a La Nina type signal persist (which it hasn't) and force the first half of summer Azores ridge eastwards extension to retrogress and force a homogeneously distinctly cooler, showery and unsettled second half of summer countrywide - such as seen in 2017. This clearly has not happened and instead we have seen a more traditional UK summer pattern emerge, still largely warm or very warm at times further SE and most changeable and average conditions further NW. The jet axis favouring tropical maritime, mostly, rather than mostly dominating polar maritime influences Compare a one year snapshot of tropical activity imprint of summer 2017 to summer 2018 A stark difference - and emphatic evidence of the role that tropical>extra tropical momentum transport has played in sustaining programmes of amplified late spring/summer ridges, whilst the standing wave regime of last year and associated lack of activity allowed a much more repressed Azores ridge to take over semi-permanently the closer high summer approached and Atlantic/polar maritime regimes increasingly prevalent Its also clear from this year how the mid to late July low frequency signal has transferred to the Pacific rather than defaulting back to the I/O and the relevance in that sense as to where we are in the current tropical cycle to early-mid July this year is very similar. Its this benchmark that the remainder of the summer and heading through September is best assessed in my opinion. This means that, overall, we should expect an Atlantic trough (not ridge) to prevail) and a case of looking for signs of the next Pacific low frequency engagement to re-emphasise a sharper trough to the west and south west and downstream European/Scandinavian ridge CFS vs 2 seasonal modelling identifies the next Nino standing wave engagement with associated surge in angular momentum tendency and tropical momentum transport beginning around the last week of the month and especially into September. Such a surge sharply reversing any interim easterly trade wind burst, and with it, any intuitive reason for mid Atlantic amplification to prevail too long Anticipating ahead comments about CFS capabilities here - these daily updated angular momentum forecasts have been consistently flagging this next upturn - and proving highly reliable and useful guides since becoming available c/o Victor Gensini maproom. Dr Gensini is co-working on developing further this maproom faciility to include further and larger data-sets with Ed Berry (former NOAA scientist and co author of the GSDM) Based on NWP behaviour since mid summer, then confidence in picking up extended signals in good time and then carrying them forward consistently is pretty low to say the least. Much as the mid July period, the models were as suggested at the time blind-sided and over pre-occupied by the tropical phase lull and were programming a mid Atlantic ridge and downstream trough to take over from the sustained heat of early to mid summer. This clearly didn't happen and instead over the ensuing days the path to a plume c/o Atlantic trough and Scandinavian ridge and a reload of heat into early August came into focus instead. In conclusion, in my opinion anyway, best to perceive any Atlantic ridge programme as a temporary blind-side to the bigger developing picture and no permanent feature- should it evolve to any extent in the medium term. Focus looks very much on an extensive ridge adjusting east with time (if it doesn't evolve more quickly from within the circa 10 day modelling) ahead of a defined Atlantic trough. As so many recent updates have suggested, this keeps prospects of further plume scenarios very much alive if nothing for a pinpoint micro scale island such as this can be guaranteed by anybody But as late winter 2018 starkly showed, it makes little difference to the weather if a season changes, it will do what it sees fit regardless

We've been working with very fine margins since the 2nd week of this month. Just look at how yesterday was modelled 8 and 7 days in advance by ECM compared to the actual outcome. At the time I said the runs looked too Nina-like with the mid-Atlantic ridge build and while this has proved correct, the difference has only been fairly small in the grand scheme of things. Yet still enough to make the difference between quite cool and warm conditions for the S half of the UK. This continues to be the case through the weekend and into next week. See here how we've seen, as a anticipated a similar move away from a Nina-like mid-Atlantic ridge build to an outcome which, while flatter, is closer to the Nino-like UK-Scandi ridge build scenario. Basically, you can see how that pattern wants to emerge, but is unable to due to the unhelpfully timed (for that) arrival of the CCKW traversing the tropical Pacific then Atlantic. ECM's newly added LP development out NW of the Azores is of some interest as a possible kick-start to the more Nino-like setup, but as already reported by others, GFS keeps it very weak - and traps it west of yet another attempted mid-Atlantic ridge, of all things - while UKMO straddles an uncertain middle ground; the low is there, more developed than GFS, but enough to travel as ECM has shown us? Anyone's guess! MWB is right to go onto BH heatwave watch though; the ingredients are there. We just need the head chef in the tropical Pacific to be in the right mood!

Interesting, looking back on previous postings...From the 14th and 17th July respectively- *I've been looking at the longer range today. To me it looks like next weekend may be a flash in the pan for more northern areas with a more NW/SE divide appearing thereafter as the PFJ sinks further S. Regardless, the background pattern is now slowly shifting, this may be in fits and starts at present but it is evident that ridging from the SW is having a tougher and tougher time becoming as dominant than it has done over the past couple of months **longer range modelling looks fairly set on a westerly dominated August now ***I did say it looked increasingly like the background pattern was changing. When you rely on surface features to prolong the heat rather than upper features which are more entrenched like the large HP we saw earlier on in the summer, the whole pattern lies on shaky ground. In general there has been an overall decline in pressure (though in no way linear) for the past couple of weeks. To me it looks as though the Azores HP is having more and more issue with ridging in sufficiently. Sometimes it is possible to simply monitor the modelling, along with the general synoptic trend and get a grasp on where we are headed in the longer term. The modelling did fairly well in this instance in the longer term.

We also now have 5 days in a row with the 12C 850s line over the south of the UK on the latest ECM mean, from Saturday until Wednesday. That's a pretty warm spell coming up?

A perfick end to summer this would be from the Ecm 00z operational.☺

ECM nice and fresh from the NW later next week . Polar opposites to this morning run . The summer is slowly petering out .

Another grey cool morning. Probably loads of mid level cloud to greet today like yesterday as well. Cool and wet tomorrow. What id do to have those warm, blue sky days back.

The outlook this morning is unchanged from yesterday so little point in repeating the overall assessment but a couple of current charts this morning does serve to illustrate the general theme very well. The two conflicting airmasses, the cooler, unstable to the NW with the jet dividing it from the warmer and more humid air to the south. The fronts along this divide come into play over the next couple of days A fairly cloudy start to the day in many areas, particularly the north west with patchy rain as a waving front is straddled across N. Ireland and southern Scotland. During the day the front will move slowly south east but during the afternoon a more substantial belt of rain will arrive over N. Ireland and Scotland and also travel slowly south east. Meanwhile the south/south east is in the more humid and warm air and where the cloud breaks it will be quite warm/ The front(s) will continue to track south east overnight and through Thursday and there could well be some moderate rain in the areas along the track, before clearing the south coast by early evening. The passage of the fronts introduces much cooler, unstable, air in it;s wake resulting in frequent showers that could well be quite substantial in the north west as embedded troughs within the circulation of the main low pass through. The showers will continue overnight in Scotland but, keeping in mind the opening charts of the post, a deepening depression tracks rapidly east on the jet and is 983mb south of Iceland by 1200 Friday with the associated fronts bringing strong winds and rain to the north and west of the country. The scenario over the weekend is quite complex, albeit fairly quiet, as a waving front trails from the low, now over Scandinavia, down through the UK and out into the Atlantic. One such wave will bring showery rain across an area north of the Midlands through late Saturday and through Sunday whilst it will be quite warm in the south east. And the NH profile at T120 is just about where we came in but the jet is a tad further north

And just to show how balanced i am, here's the Gem 12z, should please the heat haters!

Just been speaking to an old acquaintance, weatherman and author of weather books, Ian Currie. Ian has kindly agreed to perform one of his weather talks, at our over-50's Church Group, in Lee. He actually lived in the Lee area, when he was a very young boy. He may perform his talk on Frosts, Fairs and Freezes ( based on his book, of the same name.), Weather Lore (Also based on his book) or London's "Hurricane" ( based on his book of the October, '87 storm and others, locally.) He now lives in a very picturesque part of our region, Storrington, West Sussex. He's recently opened another weather station there and sends data, to the Met Office. Asked him on his views for the rest of August and the early part of Autumn. He thinks we're likely to see a wet start to Autumn, as happened in Sept.1976. He thinks we're still likely to see occasional warm spells and convective potential, especially for our south coast regions, due to the above normal Channel temperatures, after such a hot Summer. Regards, Tom.

Quite a variation for Sunday forecast . Distinct deepening low on GFS or flatter solution on MR

Indeed, the Ecm 00z ensemble mean makes for pleasant viewing with a strong azores ridge extending across southern england from the weekend and well into next week with predominantly fine and warmer weather..fingers crossed for some decent sunshine, with uppers (850's) like that it would become very warm further south!☺

A handful of photos from this year's Arizona chase, the first chase I've actually bothered with my camera!

Well unfortunately for heat lovers the ECM moves towards the GFS for late next week. High centred to the west of the UK rather than the east. Still largely settled but much cooler than the 0z.

And as usual way more than forecast. I know I mention it a lot but it’s shocking how bad cloud forecasts have become in this era of so called progress.

Here's the weekend troublemaker. As for that next possible system of similar nature, 06z GFS got closer to the 00z ECM but still trapped the low west of a ridge in the end. I expect that either the trend of GFS will continue all the way to a solution very close to the 00z ECM, or ECM will meet it somewhere in the middle (the most uncertain outcome in terms of effects on the UK).

Sigh....default British skies have returned. How I’ve missed the gloom (not). I suppose grey is very on trend now, so not all bad.

Lights on in the kitchen at 6am - here we go !!!

Good Evening Everyone, Re last Friday's thunderstorms, I thought you may wish to read the article I have attached from my local newspaper's website. https://www.essexlive.news/news/essex-news/ball-fire-spotted-floating-outside-1902507 Kind Regards Dave

I suspect that was down to how hot and dry it was!! Picking holes in this Summer is interesting,we've not had this for over a decade yet some still try and find fault with it.

There's actually plenty of warm / very warm and fine weather for southern uk on the Ecm 12z operational after the current cooler blip before it potentially cools down again from the NW later next week (some cool clean fresh polar maritime would be pleasant actually) and the atlantic high stays close and then builds in again..towards the end of August could yet be warm and anticyclonic.☺

@192hrs GFS/ECM/GEM all go rather autumnal.

UKMO looking set to pump up a ridge at T144. Could be the end of the Atlantic train for a while.

In a nutshell, the Gfs 12z operational shows a north / south split for most of the run, most of the rain and cooler temps further north, the best of the fine weather and warmer temps further south but even the south has a few cooler unsettled days too..but then, as we have seen with recent gfs runs, high pressure becomes dominant towards the end of August and this run, as with the 6z shows a lovely end to summer.☺

Hope he's right mate. We need a good soaking autumn and early winter then bitterly cold mid/late winter.

Below I've listed all the days of the top nine Summers (all those of 17.00°C and above) that have exceeded 2018's highest daily mean of 22.5°C on the 27thJuly. 1826 (rank = 2) 27th June (22.8°C) 1846 (rank = 6) None, highest was 22nd June 1846 (22.0°C) 1933 (rank = 9) None, highest was 4th August 1933 (22.2°C) 1947 (rank = 8 ) 3rd June 1947 (23.0°C) 1976 (rank = 1) 28th June 1976 (22.6°C) 1st-7th July 1976 (22.9°C, 22.8°C, 24.6°C, 24.7°C, 23.9°C, 23.3°C, 22.6°C); part of a 12-day run from 26th June – 7th July above 22°C 1983 (rank = 7) 12th, 13th July 1983 (22.6°C, 22.7°C) 1995 (rank = 3) 31st July – 3rd August 1995 (23.4°C, 24.9°C, 24.6°C, 23.4°C) 2003 (rank = 4) 15th, 16th July 2003 (22.6°C, 22.7°C) 5th August 2003 (23.1°C) 9th August 2003 (23.9°C) 2006 (rank = 5) 2nd July 2006 (22.7°C) 19th, 20th July 2006 (24.5°C, 22.7°C) 25th, 26th July 2006 (22.7°C, 23.2°C)

Day 1 Convective Outlook VALID 06:00 UTC Wed 15 Aug 2018 - 05:59 UTC Thu 16 Aug 2018 ISSUED 21:11 UTC Tue 14 Aug 2018 ISSUED BY: Dan Subtle forcing aloft may be enough to release pockets of marginal mid-level instability, and hence a risk of isolated lightning, along the cold front as it continues to slide SE-wards from Irish Sea / NW Wales / N England initially to Lincs - Dorset by Thursday morning. Most areas of England and Wales will remain lightning-free, however. Strong deep layer shear could produce some elements of line convection at times. Some model guidance suggests the potential for showery rain and perhaps some embedded isolated lightning during Wednesday evening over southern Scotland, running NE-wards across eastern Scotland and out to the North Sea. Otherwise the main risk of lightning during this forecast period will be western Scotland (Highlands and islands) and western portions of Ireland, especially later on Wednesday night as steepening lapse rates overspread the area courtesy of cold air aloft associated with an upper trough, atop warm SSTs. Skinny CAPE, weakening shear and limited convective depth prevents an upgrade to SLGT for now. http://convectiveweather.co.uk/forecast.php?date=2018-08-15

Goes east at 1200 UTC We might cop some nifty sunsets from this dust

Annoying amounts of cloud today.

i put it in a pot so it can be moved indoors in october when it snows

was expecting a better day to be honest given the forecast - 21.3c and completely overcast if the cloud cleared you would imagine it would be very warm... still its dry at least I guess another typical August day.

You may need to move it indoors now, especially if it’s a watermelon or it won’t ripen

Same here. The sun tried to come out earlier but the vile grey cloud has completely covered the sky, now Am missing the sunny skies, too. But it’s dry and usable weather, again, so it could be worse. And grey is so on trend at the moment. Currently 22C with moderate SW’ly winds.

Interesting how the ecm promotes and develops the low that starts life over the eastern US at T72. See how this goes this evening

Those fantastic nights in in front of the fire are just around the corner,can't wait!

Very noticeable the loss of light on an evening now. Looking forward to cool September evenings and misty mornings

The track of the little weekend wave

January and December 2010 are probably my two favourite months winter wise. December 2010 was in fact stunning for its rime frosts and then its snowfall just before Christmas. Christmas day 2010 itself was stunningly beautiful with sunshine against a white, snowy landscape. I will count myself extremely lucky if I get to see another winter month like that before I pop my clogs.

mine is in a pot in the garden

Thank you Going to try it tomorrow. It’s much bigger than a tennis ball, smells good. How was your carrot? Hope your melons keep swelling!

Synoptically perhaps not....but when you have the driest first half of summer recorded, the third warmest July on record and one of the warmest may and June’s too it makes up for it!

WOW.

I don't disagree with anything you've said, but I think you've missed my point somewhat. Apologies for not making myself clear. My point was about people's perceptions. Someone on here commented that people nowadays would really have struggled in the aforementioned 1980s Summers given that the overall temperatures were that much lower. My point about the short strings of days that skewed the overall figures in the cases I mentioned was that the monthly statistics are not representative of people's perceptions of how the months actually were. When most people judge a particular month or season they will do so based on the dominant theme, and not on the few oddball days that were different. Based on CET figures, June 1985, for example, was cool from start to finish. But the actual daily means were comparable to those of June 2012, barring the hotter days that the latter saw towards the end. Thus, when people compare the two months, their perceptions of temperature may well be very similar, despite the disparity in the monthly figures. Don't get me wrong, in most scenarios I'd quote the monthly figures. But the comparisons that people are making on here seem largely to be based on their subjective experiences.

You only need to check this site for the record flooding of that strange period from 2007. Worst summer flooding in living memory.exceptional flooding http://www.trevorharley.com/weather_web_pages/2007_weather.htm Going back to july 1980 that was pretty cold going back to the 80`s.

I would say it's an outlier, the GEFS 6z mean in that timeframe looks benign..back to the more reliable, this coming weekend and early next week looks better for southern uk as the azores ridge builds in across southern england so becoming predominantly fine and warm further south and then late august indicates increasing chance of high pressure becoming centred close to or over the uk..inbetween, more changeable with temperatures close to average..best chance of fine and warmer spells further s / se..most unsettled and coolest far NW.

Nice solar flux drop.

So not "barely above 17C by Wednesday" then? Calls of this August being poor are premature. There's only been 11 Augusts above 17.6C in the entire CET series and we're looking to be at around 18C with less than 10 days of it left.