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The outlook remains changeable without anything of any note skulking in the woodshed . The pattern is quite well illustrated using the EPS short term NH 500mb anomalies for last evening. This shows the main vortex lobe N. Canada with subsidiary south of Iceland and with the Atlantic sub tropical high trying to push north this results in a quite strong, but fairly anaemic westerly upper flow with a mainly positive anomaly, But within the main westerly pattern the strong thermal boundary between the air masses (a.k.a the jet stream) will wave as the airmasses phase and thus alternating airmass influences over the UK but tending towards a N/S split and warmer interludes in the south, Thus the changeable weather, The detail of which of course the det. runs sort. Last evening's storms have dissipated as the upper tough moves east and this morning it is mainly dry but with varying amounts of cloud but more so in the north. The story of the day really, cloudy with sunny intervals, but an area of rain will quickly impact N, Ireland and central Scotland as a small frontal system tracks north east leaving a cooler, showery regime in it's wake. Drier and warmer in the south. The system will quickly pass through so a relatively dry and clear night in the north and certainly in the south and east but rapid changes are afoot as the next frontal system associated with quite a deep low south of Iceland bring patchy rain and strengthening winds into NW/W areas in the early hours. Followed by more intense rainfall in N. Ireland and Scotland by 12 as an active cold front arrives on the scene. Drier and warmer south of the front as it tracks south east down the country. (touch of the Foehn Effect in the NE?) The front continues its journey overnight and through Thursday, clearing the south east by lunchtime, leaving much cooler air in it's wake with some quite hefty showers in the north and west on the quite strong NW/W wind. But all the while the next upper low is getting organized and about to track quickly east north of the jet ( pretty much as mentioned in the introduction). On the surface this results in a deepening surface low tracking rapidly east to be 978mb between Iceland and Scotland by 1200 on Friday with heavy rain and strong winds, possibly gale force for a time, effecting N. Ireland and Scotland. with the rain then reaching as far south as the north of England and N. Wales on a generally quite cool day. Quite a messy picture on Saturday as the low has scooted north but with other systems waiting in the wings to the west and a front straddling the country a brief, cooler and showery in the north and cloudy and warmer in the south, description will have to suffice. And the NH profile for T120 which is just about where we came in.

I have to say that looking at my trusty 500 mb anomaly charts there is little sign of any major shift in the upper air pattern in the next two weeks. Of course they may be wrong but it would be unusual for none of the three to not be hinting at some kind of change in the pattern they are currently showing. That is for a fairly benign westerly pattern to persist. Individual days, maybe 48+ hours with a temporary ridge developing close by the UK but no indication of major heat returning. A NW-SE split is likely with the driest and warmest for the SE. The links are below http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Fully agree, I don't think anyone has said there's another heatwave on the way, just occasional azores ridging further south, like the end of this week for example whereas northern uk, especially the far NW bears the brunt of the coolest most unsettled conditions..the predominant very warm settled pattern this summer is well and truly broken but I still think southern uk can look forward to some decent fine and warm spells, especially the southeast corner.☺

Yes that is right, the GSDM is essentially a diagnostic tool to both assist and check the NWP interpretation of global wind-flow (the jet-stream) as measured in both the tropics and extra tropics. As a checking mechanism, it is used in a direct practical reality - and is therefore much more than mere theory I think that separating the tropical element (MJO) and extra tropical element (GWO) as a means to try to debunk the rationale shows an inherent lack of understanding of the actual purpose of the GSDM itself. The GWO, as the extra tropical element of the GSDM takes account of the momentum transport of frictional eddies in the jet stream caused by changes in direction, convergence, speed and velocity of wind-flows, and then the subsequent propagation of these frictional eddies via mountain torques leads into rossby wave dispersion in the extra tropics - that links global >regional scale circulation anomalies. Putting all this into less presentational and simpler terms, it becomes possible from this process to match up the identified circulatory anomaly framework from the diagnostic approach (global and/or regional anomalies) with the one identified by the commonly recognised numerical modelling systems. Hence some extra insight into NWP performance and accuracy. The purpose of the GSDM is not in any way to replace numerical modelling but it is a highly important diagnostic supplement to it. Such a circulation anomaly as above, is a sum of all its parts. With such a critical link in mind, discounting the influence of upstream signals in the Pacific as only having any influence on the US and not the Atlantic /European pattern appears to pre-suppose that the jet-stream ribbon (as measured by GSDM diagnostic) gets off a train at Myrtle Beach and boards a disconnected line somewhere off the Eastern seaboard of the US Its also clear that accuracy and correlation will not be obtained alone through the use of MJO composites, because this is just one element of the GSDM and leaves out extra tropical responses as described above. Rossby wave dispersion from tropical convective activity propagates to the extra tropics according to its wavelength - (i.e how far east and at what amplitude it propagates within its usual 30 to 45 day periodicity cycle) and as "a mini-cycle" in itself that is where the ENSO link is made as determined to where the base standing wave signal exists which the low frequency MJO signal attaches itself to. The relevance to this particular summer is the slow transition that has been underway from La Nina base state towards, of late, a very weak fledgling El Nino state and how the ocean>atmosphere link would evolve according to this. As you correctly say @Singularity much of the focus has been around how fast the transition between Nina towards Nino would occur, but again to re-state, the talk here is not about the base state per say - but about how would the atmospheric relationship to the ocean base state play out in terms of the tropical/extra tropical interactions as described above to link global and regional circulation anomalies. And we think of the Atlantic and European regional circulation anomaly as being as much linked as the Pacific/US regional circulation anomaly is to the global circulation as a whole 'Teleconnections' has become a very overused and over applied word. The diagnostic process of the non numerical model is much more than mere indices teleconnection play-matching. The GWO composites, as a mere end product of that diagnostic process, are made up of the tropical and extra tropical element aggregate of global wind-flow according to the ocean/atmosphere relationship relative to the base state. Whilst its true that these composites can be used more reliably towards a pattern guide than any MJO composite - for the reasons clearly given the emphasis remains firmly on diagnosis rather than pattern match and theory. Certainly for someone like me who isn't at all interested in being any competitive forecaster, but simply looking at what might supplement/influence the direction of NWP and making suggestions according to this. Interpretation is required according to any given number of variables that might be present at a given time - and as such any rolling assessment of a given pattern or change in pattern is taken on its own merits rather than relying on any analogue. Less theory and more reality. I think that any emphasis on this type of model approach being theory rather than having any direct practical approach can be behind the attempts for a few, usually the same few, thinking (wrongly) it is easy to discredit. But, hopefully that is the very last time, any of that needs to be repeated... ….To the present day modelling: The last post on Friday GSDM raw data identified the GWO in Phase 4. Phase 4 of the GWO identifies westerly wind bursts being added to the global wind-flow circulation which start increasing momentum flow across the Pacific and a split-flow occurring downstream of this energy which separates a downstream trough and subsequent ridge. The amount of amplification of this ridge is determined by the degree of split of the flow coming from upstream that determines sharpness of the pattern. In this type of scenario, according to the current seasonal wavelength, increased upstream amplification (lower AAM) will produce greater amounts of directed polar jet flow downstream and provide initiative to the trough and produce a flatter ridge response further downstream from that. The converse holds true. Subsequent update of that raw GWO data (two days + consolidated) has identified the initial calculation as too progressive in upstream momentum (and hence too much downstream split-flow amplification) and the GWO has remained at a lower amplitude and more indiscernible signal Phase 0 than initial raw data suggested. We can only work with the date we are supplied with - that is the same for any computer supplied data. Working ahead from this changed starting data to assess ahead, this will account for the apparent continuing stubbornness of NWP to not amplify the ridging more than seemed logical from the former data The present GWO amplitude is also reflective of the fact that the tropical cycle in late July was the first one to engage the newly developing Nino footprint in the Pacific and it served mostly to wipe out the greater excesses of easterly wind inertia accrued through two years of La Nina lag which has been taking its time to be eradicated completely from the global atmospheric circulation.This is accordingly set against total global atmospheric angular momentum levels which are reflective of the GWO orbit position and has been hovering either side of parity. The GWO vs GLAAM position at any time is an excellent barometer to gauge perspective of how much the tropical cycle may serve to change and evolve the global vs regional anomaly patterns (linked to above discussion) Relative angular momentum tendency has recently stayed buoyed up through the persistence of tropical activity in the Pacific (non low frequency signal). This has been keeping angular momentum in a holding position till the next low frequency tropical cycle arrives as catalyst to boost the extra tropical circulation via another surge of poleward momentum transport and boost amplification of the pattern. Further poleward momentum being a signal for another rise in both relative and total angular momentum and reflecting greater advance of the atmosphere in embracing the growing El Nino signal in the Pacific. A fly in the ointment over the coming 10 days is the passage of a convectively coupled Kelvin Wave traversing the tropical Atlantic (dampening the Pacific storm signal temporarily and providing a window for Atlantic developments) at the same time as the low frequency MJO signal is ending latest cycle in readiness for the next. This will possibly see a short phase of greater trade winds keeping the lid on angular momentum briefly(and facilitating Atlantic tropical storm development before suppression occurs once more). This also means the broad-scale downstream pattern is unlikely to amplify sufficiently in this time to shift the Jetstream further north to encompass the greater part of the UK. It seems this is also combatting a greater temperature gradient relative to late summer polar vs summertime tropical cell Taking all into consideration, not too bad an outlook overall at all further south bar a few days, but something of a frustrating spell for those further north with support for the flatter changeable pattern and the north/south split into the last third of August, It looks to me as if the ensemble data continues oscillating around the position of the jet relative to the restricted amplification equation (for the time being) within a narrow upside/downside pendulum. The 12z giveth and the 0z taketh away etc. . But the lack of faith in NWP picking up signals coherently with poor guidance and continuity in extended data (and professional extended forecasts flip-flopping accordingly), the lack of pay cheque involved in making any suggestions ahead of time (whatever they they may be), and just the plain old devils advocate in me still clearly sees the potential magnitude of the next tropical signal cycle into the Pacific (echoing the synoptic passage of late July) and setting up an end of season plume scenario as discussed in the last post

You just can't beat a man with a good handful.

Impressive girth on your melon !! Must like the heat.

This morning's clusters on the whole favour a delay on next week's trough, generally now reaching us during Wednesday (better chance of heat) The idea of NE heights for the BH weekend has grown, too

Certainly seems that the weather has made fools of us again. A flat zonal pattern seemed like the most unlikely of outcomes a couple of weeks ago, yet here we are. We keep hearing that the models are playing catch up with regards to any ridging, yet this keeps getting pushed back.

Although monthly statistics don’t reflect it, people shouldn’t underestimate how cool some of the Summer months from recent years have been. June 2012, for example, was for the most part very cool, but a hotter spell at the end of the month was enough to drag the monthly figure from well below average to below average. The CET to the 24th was just 12.7°C; had the weather not been as forgiving in the final few days then a sub-13°C finish (like 1985 and 1987, the two coolest of their decade) would have been likely, which would have put it in the top 30 coolest in 360 years of records. In terms of maxima, which is what many people’s subjective experiences of Summer temperatures are based on, June 2012 (17.4°C) really wasn’t that dissimilar to the Junes of 1985 and 1987 (16.5°C and 16.8°C, respectively). July 2012 also suffered a similar fate when a short string of hot days at the end of the month skewed the monthly figures. For the most part, this month was also very cool, with sub-14°C CET daily means occurring frequently throughout. Then the rainfall figures top the 1980s Summers quite convincingly. The Summer EWP figures for England & Wales place 2012 as the fourth wettest Summer in 252 years of records (375.0mm), while 2007 was the twelfth wettest (343.5mm). Summer 1985 was the wettest of the 1980s at 36th wettest (293.0mm). In particular, the Junes of 2007 and 2012 can also respectively boast being the fourth wettest and outright wettest on record. Onto another point, is record-breakingly cool weather still possible in the Summer months? The last record low CET daily mean that occurred in Summer was 25 years ago (10th July 1993). Breaking daily records may be tough, but I believe exceptionally cool weather is still possible. July 2015 managed just that: owing to north-westerlies off a very cold north Atlantic, the mean CET for the final week was just 13.6°C (eight-coldest for this period out of 247 years). That was enough to drag that month down to slightly below average despite the exceptional heat at its beginning. With the potential for a very cold north Atlantic to persist in the years to come (due to a weakening AMOC), then perhaps spells like that of the end of July 2015 could become a little more common?

Just looks fairly average joe really - probably why there’s so little chat in here! The most boring period of the summer for sure. No one (well less people) are really interested in bang average weather, and that’s what we’re getting.

Despite some attempts on some op runs to edge towards heatwave territory early next week, the percentage play remains as it has done for days - a few good days in the south before a front crosses around Tuesday. The clusters last night suggested this front may not actually developing as planned (that's how we might get the hotter runs) but most look like pushing a trough through shortly after this chart, which is for Monday Further out, lack of a discernable pattern change, so still some settled and unsettled spells (the latter most frequent in the NW), but this chart for the Bank Holiday was an interesting first effort, two clusters with heights slightly lifted over most of the UK, and the third with a trough stalling to the SW (thunderstorms!) Little sign of below average conditions aside a say or two in the next two weeks, anyway.

From London this afternoon:

Blown away as always by Tamara's ability to put so much detail together coherently in a single post . That CCKW has been causing headaches but (due to a Tamara post I read last winter I think) I wasn't expecting that to be strong enough to cause much trouble for getting at least a bit more amplification to the flow next week, indeed it seems like the models have been overplaying it - but by the wording of this latest post, I'm inclined to be more cautious now as opposed to expecting the Nino standing wave to essentially 'drown it out'. With a small tropical disturbance having been added to the weekend mix (as if we didn't have enough complications already!), minuscule adjustments to how flat or not the jet stream is will make a big difference to what we experience Sun-Mon. For the south that's mostly how wet or dry it is, while further north it also separates warm from cool. Compare the 06z GFS with the 00z GFS or ECM and you can really see what I mean. Then for the rest of next week, it comes down to CCKW v. Nino standing wave and how fast the next MJO cycle gets going. Ensemble spreads suggest that last player could get going as soon as next Monday, but that has to be seen as an optimistic outlook if it's used. Regardless of next week's timings, though, the prospects for an unusually warm/hot final act to the month are indeed in evidence. 10 days from now - the most delayed scenario in terms of the positive AAM surge - puts us with a week left for August to redeem itself in the eyes of heat lovers. It's been a difficult month, and lately it's been down for most of us, but odds are it's not out for the count.

yeah im looking foreward to mushrooms too.....

Talk about summer of 1986, how many people realise that over a 1/5 of summer's 1986 rainfall total for England and Wales was contributed by the remains of Charley? Overall, summer 1986 was not a wet summer.

Thank you, everything swells in the heat

Sunny and 25c now. Cracking afternoon after a dull start.

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.

Very autumnal here this morning with heavy rain and 14c. Neeps and grass loving it

Last year all the long range models were showing a very mild winter (remember those orange and reds?) but in the end it was not that bad and March delivered the goods.

Modelling pretty agreeable for the weekend (and it’s a shame about the ex-tropical low looking likely to interrupt the drier spell for the central belt), but after that, I find any northward building of ridges west of the UK suspicious; as Tamara detailed yesterday, the interference of the CCKW promotes a flat westerly pattern until a Nino-style ridge can build through the UK and into Scandinavia. Not build west of the UK. Modelling probably trying the mid-Atlantic option due to initiating the MJO too far west. So while cooler air may well cross the UK again next week, there’s a good chance it will be for a shorter time than the morning model runs are suggesting. Leaving the longer-term alone for now; models are yet to coherently move the MJO as far across the Pacific as anticipated. Hopefully they’re missing something there.

18.1 to the 13th 2.1 above the 61 to 90 average 1.2 above the 81 to 10 average __________________________________ Current high this month 19.9 to the 6th Current low this month 17.7 to the 1st

I hope we get some more sunny days. This isn't my idea of one....

If that could be bottled i would buy it... One of the best fragrances around,love it. I can actually smell nature without sneezing through runny eyes!

Daily sun: 14th August 2018 Sunspot number: 0 Current Stretch: 11 days 2018 total: 132 days (58%) The Radio Sun 10.7 cm flux: 68 sfu

The ecm take for the end of the week finds the low 981mb south of Iceland with associated fronts and strong winds already effecting the north west at 1200 on Friday. These quickly clear before a wave arrives over the same area and the west by 00 Sunday.The south/ south east remaining relatively dry and less windy. The 0600 geostationary

Cool and wet here again today. A carbon copy of yesterday though the rain did die down later. A max of 15.2C so not much warmer either.

this summer has been too hot and now it's too cold is that moany enough for this thread?

Florida Gov. Rick Scott declares state of emergency over red tide https://wsvn.com/news/local/florida-gov-rick-scott-declares-state-of-emergency-over-red-tide/

Sunshine here N.

Cgs goin off everywhere... https://m.skylinewebcams.com/en/webcam/italia/toscana/lucca/marina-pietrasanta

In your neck of the woods, August is the sunniest and warmest month of the year on average, as it is in many southern and eastern locations. Admittedly, August has been rather lackluster in recent years but that is a tiny sliver of climatic history. Or perhaps you haven't been alive for very long so recent Augusts constitute most of your living memory? We'll get another 1995 or 2003 in the next few years, then all of this 'what happened to August' malarkey will disappear.

Can we save the autumn talk for the autumn thread? I don't want to read about it in the summer thread.

Nice line of cells over eastern England and frontal cloud gathering west of Ireland on the 1800 geostationary image

Aha football season must have begun, Karlos is back, reinvigorated and prepared for the forays into the MAD thread... welcome back..

Manchester summer index has 2008 and 2012 with lower indices than those 1980s summers.

Some cells around the convergences zones on the 1316 UTC MODIS and some Cbs on the 1300 chart

any signs of summer returning .. or can I expect a Wenger return more likely

The high res. MODIS at 1130 UTC And

Latest update all quiet KILAUEA VOLCANO (VNUM #332010) 19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m) Current Volcano Alert Level: WARNING Current Aviation Color Code: ORANGE Kīlauea Volcano Lower East Rift Zone (LERZ) During an overflight of the LERZ this morning (August 11) two small ponds of lava were observed in the Fissure 8 cone. One pond is crusted over and stagnant, the other is incandescent and sluggishly convecting. A gas plume billows up from Fissure 8; low-level steaming from a handful of the other fissures (inactive) is intermittent. Lava is oozing at several points along the coastline creating wispy laze plumes. Although the lull in LERZ activity continues, it is common for eruptions to go through periods of diminished output, or to pause completely, only to return with renewed vigor days or weeks later, or longer. Resumption of the activity on the LERZ could occur at any time, and residents should remain informed and heed Hawaii County Civil Defense messages and warnings. Kīlauea Gas Emissions SO2 emissions from the summit, Pu῾u ῾Ō῾ō , and the Lower East Rift Zone are all at low levels. LERZ emissions on August 5-6 were ~ 200 tons/day; Pu῾u ῾Ō῾ō emissions on August 6-7 were 200-300 tons/day, and Summit emissions when last measured on July 19 were around 100 tons/day. This SO2 release represents the lowest SO2 emitted from Kīlauea for over a decade. Despite the low emission rates, SO2 plumes were blown toward populated areas in east Hawai‘i by SE winds on August 9, and many individuals reported detecting the smell of sulfur. Weather conditions contributed to this, but in addition, as the eruption vents cool down, small amounts of H2S are generated. The human nose can detect H2S at very low levels, adding to the overall perception of increased sulfur emission. Kīlauea Volcano Summit It has been over a week since the most recent collapse event at the summit on August 2. Summit seismicity continues to be low, with only 2-3 located earthquakes occurring per hour (maximum magnitude of M2.0). Summit deflation is negligible. HVO will continue to monitor Kīlauea closely for any signs of change in activity. The next status report will be issued tomorrow morning unless significant changes occur.

Caught a Perseid on my timelapse earlier this morning.

There was a good display of noctilucent clouds before dawn this morning.

Caught a couple of Perseids on my timelapse the other night

Couldn't have been more wrong if you tried William !! Thunderstorm and torrential rain right overhead of me as I type.

Little capture from yesterday evening lovely storm never really stopped, things ain't looking amazing but we shall see plenty of time for change I'm expecting some downpours to start developing ahead of the main activity around Channel Islands

One of the best Elevated Storms I can remember here in SE Essex hit at 3am, rudely woke me up but these were worth it. Bring on tonight! The last few literally were hitting a few hundred yards away so even I retreated to the Kitchen whilst the bad boys were striking! Paul S

Not a bad night at all!!

This just in,live footage of William's channel crossing....

This explosion here is what we like!