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looking at the 3 500 mb anomaly charts I use for trying to suggest what the upper flow will be is not easy at the moment, if indeed possible. Two suggest one thing the third shows nothing much like the other two. The odd one out is NOAA which is 'usually' nearer the mark to what the upper flow turns out to be in the 6-10 day time frame. Currently is keeps its idea of several days, a broad westerly Atlantic flow which turns S of W over the UK ahead of a broad trough close into NW'ern areas. Beneath this in the right exit of the flow it does suggest a very slight indication of +ve heights with a slight ridge from the bottom of the trough into western Europe, see below http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php Its 8-14 version is pretty similar. So this could give a possibility of surface pressure rising in this right exit area from the upper trough. The ECMWF-GFS version is much more definite over the past 2-3 days for height rises coming out of Europe from about the meridian eastwards over the UK, especially GFS which keeps showing quite marked ridging from western Europe over the UK towards Greenland. http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html Usually I would stick wuth NOAA but as it does give the slighest hint, no more, of that idea and the similarity of the other two to each other over a couple of days then conditions may be right for some build of heights at 500 mb and beneath this at the surface over western Europe and possibly over the UK (could even be centred over the UK). If we look at the link below. UK Fax charts, scroll to T+120 first and notice Exeter show a high tending to build from the actual for today over western Europe. Scroll down further to see how thie own 500 mb prediction looks. It shows a definite change from a trough dominated chart just east of the UK to a ridge type in 5 days time. So this idea of heights building at 500 mb and subsequently at the surface may prove correct. We should all know 120 hours down the line. How long this might last or indeed how much dry and warm weather this may produce is a bit problematical as well as how far north this pattern might extend its influence. All in all a very interesting set up.

Models finally working themselves into a typical early September pattern, which is lots of sunny weather - and increasingly looking like Northern areas will indeed join in. I still have a sneaky eye on developments at T144 — the GFS idea of the splitting Biscay low is not too be ruled out, and could lead to a little heatwave at the start of next week is verifies. Slight outsider at the moment.

That was a barnstorming ECM run for a late summer special. High pressure reaches the UK by, well, 48 hours time, and bar a couple of dead fronts, that's how it stays throughout the run. Good to see northern areas looking in the mix for summery weather too, though don't tell the kids This morning's ensembles finally banished any thought of unsettled weather returning quickly to northern areas - actually a bit of a turnaround on 48 hours ago - but the overwhelming backing for UK-wide settled spell is difficult to argue against when you have two clusters so emphatically in that direction even by T192 and T240 (5th Sept and 7th Sept) So I'd suggest anyone with a UK holiday booked next week won't just benefit from cheaper prices but very good weather too, probably all week. This is the absolute earliest that we see any sign of unsettled weather possibly returning from the NW, and that's on a 31% cluster (so 70% still very settled) - and we're out to 10th September here in any case: Maximum temps - well, we're out of high summer so need to be realistic, but still some hot feeling days with Sunday/Monday up to 25C ish, low 20s for much of the week but creeping back up towards the end of the week. The only way to beat that is to see the stalling low to the SW that the GFS has suggested on occasion, which may allow us to approach the 30C mark once more.

Interesting to see the GFS 06Z following the idea of the earlier run with that low over Biscay still there- it would certainly be a notably warm start to September if that came off. With that continental flow it would also be very sunny for most as well. Promising signs.

That's a very sweet finish to a nice Ecm 12z run dominated by high pressure..wonderful NH profile at day 10..now that's what I call finishing on a HIGH note!☺

Howzat! ECM T240, country wide!

Great- Fits in nice with the September forecast & anomaly chart....

@damianslaw - I think the heat chasers got model fatigue this year, it's been a cataclysmic season! So I think it's going to be a slow month on here! MWB and Frosty are hardcore though Right back on topic... ECM ensembles look pretty much unchanged - settled, warmish daytime, keep a jumper handy first and last thing.

Oh its September looming and once again, high pressure on the scene. Indeed early September on average is the quietest time of year weatherwise, atlantic often goes into a slumber.. so many times - any reason why this keeps happening? Alas, a very pleasant outlook for all, though western parts will see a rather drab dank weekend ahead, and will have to wait until next week - just in time for the schools going back (I feel for the kids this year, it was a shorter holiday locally here, 27th July and ever since its been a gloom fest with plenty of rain and consistently underwhelming temps, they go back early next week - and the weather reverts again, becoming a common theme..) September is a great month for outdoor activities, humidity begins to ebb, and maxes in the low 20s under a blue sky and sunshine don't roast you unlike in June and July, you can just about get away without suncream, though can burn still. However, I've found myself quoting the title of the song 'wake me up when September ends' many a time in recent years - it can be an ever so dull month weather watching / model watching, and I suspect I will quoting it again this year...

What next, people filling net weather with winter forecasts?

Last evening’s EPS mean 500mb short range anomaly indicating some retrogression of the trough to the north west that would tend to back the upper flow a tad further west and thus facilitate the Azore’s HP ridging north east and the influence of high pressure over the UK albeit still tending towards a N/S split to some extent. Temps would then rise a little from just below average to just above but perhaps with a fair bit of regional and diurnal spread and generally quite dry. This should become apparent on the overlap at the end of the short range if the prognosis is on the money. Back to the here and now and not a bad day in prospect in most areas with some early morning Sc tending to break up during the day so a fair bit of sunshine and feeling quite warm in the light winds. But during the afternoon a band of rain from the front associated with the low south of Iceland will edge into N. Ireland and western Scotland and progress slowly south east. Apart from the cold front continuing to track south east overnight and through Wednesday, weakening en route, a further complication is the thundery outbreak (mentioned in earlier posts) over France that is likely to track north east during the early hours of Wednesday and impact the south east. Apparently there is still uncertainty about the detail of this. Behind the front in the north cooler and showery weather. By Thursday the weakening front is away to the south east and a ridge quickly builds over the UK portending a not unpleasant day with broken cloud and sunny intervals with temps around average. But it worth noting here (as mentioned last evening) the arrival of another lobe of the vortex over southern Greenland with a lot of energy flowing east to the south of it. Thus by Friday the pressure on the ridge is slowly taking it's toll and although another pretty good day is on the cards with again broken cloud and sunny intervals after a chilly start, cloud and some rain will arrive in the north west from a plethora of fronts associated with the deep surface low in the Denmark straits. And on Saturday the aforementioned fronts will track south eastwards down the country, weakening against the ridge as they go, so probably only light, patchy rain and staying dry and quite warm in the far south. And so to the NH profile at T120 and to the question posed yesterday evening, are we going to get agreement on the evolution of the developing Atlantic trough?

Evening All - Its been a long long time since I opened a thread - So I will try to make it interesting... The first dip of the toe into Autumn is for many of us the change in mindset away from summer heat & into the ever shortening days & colder weather... Traditionally as we head through September & especially October the vortex & westerly jet increases to a point where the probability of southerly warmth is significantly reduced in probability- Notable dates in the diary for this is around the 10th of October onwards where the winter time Stratospheric vortex is ~ half of its winter peak speed @ ~ 16-20 M/S Westerly. Shapes of high pressure through 40- 50N should be flat & the mode of the AO / NAO historically reads as a positive... There is one other important Teleconnection that I never hear anyone ever mention but Ive kept revisiting it each winter for about the last 5 / 6 years is the POL ( the polar eurasia pattern ) The loading pattern for POSTIVE PHASE is measured across Northern Russia down to about Mongolia & is a similar measure to the NAO - The more POSITIVE the phase the lower the geopotential heights are over Norther Russia supporting a westerly circulation So + AO + NAO + POL all indicate a traditional zonal flow. To emphasise this the 90s was where the jet was roaring & the AO & POL certainly in autumn months peaked heavily positive So all said & done taking into consideration natural variation between occasional stronger & weaker years & of course ENSO phases we generally see a uniform process to our weather through Autumn which decends into 'westerlyness' - & this years Autumn forecast would seemingly be very straight forward if you wanted to pluck out things like matches from ENSO state & QBO phase & of course they 'could' still play their part however ENSO will be solid Neutral for SON & QBO will be dwindling Easterly - Anyway- What changes do we see potentially impacting our weather & the imposed 'Westerlyness' ... Pattern Induced Climate change is probably a phrase thats not bantered about to much but it certainly will be in the coming years- The globe is warming however the poles are warming much faster than the average annual rate - this is creating a NEW ( circa 2007 onwards ) feedback loop over the polar cell & * SOME * of the mid lattitudes - It is causing autumn tropospheric decoupling from the stratospheric vortex & it occurs in the low sea ice areas ( or more specifically the areas with the biggest negative anomaly to the norm ) What we have seen since 2007 is not only the decadal average of sea ice decline ( especially August / Sept & Oct ) but also focal points of significant negative anomalies in areas close to where the POL teleconnection is measured. The Barents / kara & laptev seas have all been in the 'ice news' for the wrong reasons & the graphs below show how this summers ice coverage has taken a real beating - The 3 above are in Anticlockwise order from Scandi Eastwards - Notes being * Barents melting out early like the decadal Trend * The next in line Laptev taking a further hit this year - being probably the worst on record * Kara as well - under the decadal ave & close on record lows - - Its also worth noting how far away they are from the 70s / 80s are - imagine how far they would be from the 50s & 60s ! The net fallout from this is the amount of residual latent heat in these areas through Autumn & *Possibly* now Early Winter & what the net fall out is - the creation of a new feedback loop of Positive heights In Northern Russia. This is also probably the net reason 'globally' why there is a reduction in the overall jet speed & depth of negative geopotential heights because of the reduced Thermal Gradient.. This illustrates well if you chunk up Sept & Oct 500 height anomalies charts for 1948 -1990 The base period 1990 - 2006 a fairly significant 16 year phase of ice loss 2007 -2017 the last 10 years in ice loss creating this new feedback loop & pattern change. We see a CLEAR Modal change in the height field over the pole - especially concentrated over the 3 weak ice areas. Lets reintroduce the POL teleconnction to include the last decade The mode has swing to a very sharp -POL especially in Autumn but not exclusive. The data indicates ftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/poleur_index.tim That 2007-2017 Sep / Oct / Nov 20/30 months have been negative with 9/9 on the last 3 Autumns !!! 100% Its also about the 'negativity' of the mode as well - going off the scale more recently.. So Bringing that back to this Autumn & NW Europe the net effect is that the eastward propergation of the atlantic is expected to be weaker & weaker - so for Western Russia we could be promoting an earlier signal for Colder weather developing - This signal fades as we come SW towards Norther & Central Europe, however the extent of the high promotes higher probability of early warmth from the south but again later into Autumn could also promote Colder air filtering through - The UK sits as ever at the end of the blocking - & whilst its immediate impacts may be slightly tempered its still expected to impact us ... but how? I would consider the following in terms of probabilities !!! NOT forecasts... * Higher probability of warmer phases in Sept Oct in particular from the south & East * Higher probability that the atlantic jet will be displaced further NW towards Greenland ( although occasional split jets towards Spain & portugal as well ) * Rainfall - Probability should be that its drier however we could up in the unique scenario where the westerly jet runs out of puff over the UK & its very wet ( the weather becomes stationary ) - this would be very unlucky. Also short periods of very high rainfall could occur * Whilst the probability remains high that it will be warmer than usual - the locality of that blocking high means that as we transition through Oct & Nov the chances of early season chill & cold could also be higher- We could see drastic swings in the weather from extreme Mild & warmth to Cold as the jet flow will be buckled... - Also there could well be some overlap into December in these conditions - Highlghted below-- The transition from Autumn & Winter this year will see the usual array of teleconnections to measure up- Currently - ENSO appears to be Neutral out to December, possible low end El Nino, critically here the lower we stay the weaker the impact will be - QBO - decending Westerly at the moment, whilst this isnt great in the long run the effects of the 'westerly' are unlikely to impact until the late part of winter perhaps reducing the prospects of a SSW ( other factors like MJO activity may support either way ) - Sunspot activity continues to be at a low point in the cycle which is a huge positive- - The troposheric disconnect that may well run through sept > Oct could Extend to Nov > Dec for 2 reasons * The feedback from the ice anomalies is so significant that if on average the signal in the last decade is muted out mid Oct - then how long will the new record low take to mute out ?? Another 4 weeks ?? Plus the wildcard this winter may be that theres support for the feedback from greenland in the form of more warmth due to record low ice here as well Plus the stratosphere is being modelled to be weak- The mean of the all the CFS runs should be taken with a pinch of salt - however its modelling significant weakness as we head through Oct & Nov - Further delaying the onset of the westerlies... So there we go as I see it - Autumn - Blocking to the East supports weaker westerlyness - although the UK could sit on the periphery where the jet holds stationary - ( worst case scenario ) Best case scenario >> Jet up to iceland & warmth Winter - Everything is in place to positively support a blocked winter - however the last peice being the strat will only become clearer in another 8-10 weeks ... Best S

Well i am looking at a blocked scenario here,whether it materialises we shall see because as i read it we have a blocking hp cell/signal over Scandinavia a look at the cpc 500mb outlook from NOAA day 6-10 and 8-14 shows the Scandi ridge exerting itself further west and including the Uk holding atlantic systems at bay the reason i mention this is the AO and the NAO(forecast)looks to go negative for the first time-circa -2 ,well since back in March i think,now with a slowdown in the jet would mean more of a meridial pattern(amplified slow pattern) where troughs in the Atlantic would dig further south enhancing more of a plume type scenario,and i would not rule out a thundery breakdown from the south/southwest can we have this in a few months it has been a great summer which followed a very cold winter/spring,well spring got sprung.

Day 2 Convective Outlook VALID 06:00 UTC Wed 29 Aug 2018 - 05:59 UTC Thu 30 Aug 2018 ISSUED 19:46 UTC Tue 28 Aug 2018 ISSUED BY: Dan Showery bursts of rain continue across SE England and East Anglia on Wednesday morning as a piece of upper forcing clears to the NE. Lightning activity is questionable given weak instability (more likely over France / Belgium etc), with some rather heavy rain possible over Kent/Sussex in particular. Any rain should clear to the North Sea by early afternoon. Farther north cold mid-levels, associated with the upper trough, atop SSTs will generate a few hundred J/kg CAPE with several showers affecting NW Scotland and the Northern Isles. Some isolated / sporadic lightning will be possible here. http://convectiveweather.co.uk/forecast.php?date=2018-08-29

The GFS continues to show some warm humid air waft in off the continent from the S/E into next week, With some spots possibly touching 26/27/28c and scope for thunderstorms to push North.

Yes the well-known self-appointed experts I could get a more accurate forecast from my goat

The ones in which world-renowned 'experts' anticipate what's going to happen in six-months' time?

Another grey and dreary start here, but not unpleasant at 18C with light winds. Am noticing how quickly the days are drawing in now. Must be nearly time for school to begin again, according to Facebook

A unusual sunrise this morning, the cloud cover being just sufficient to make the sun appear as a orange disc (photo taken around 8am). Temperature up to 13C already so should be a pleasant day for working outside.

Summers in order with the best at the top 1976 3011995 2981983 2781955 2771911 2742018 271 (up to 27th August)1984 2711959 2691975 2681949 2671989 2621947 2551933 251

Looking towards the Gross Glockner Range/Moltaler Glesher this afternoon on the borders of Salzburgerland/ Carinthia. C

So I asked a simple polite question and my post has been deleted with no explanation at all???? What a joke.......I assume from that response then that nothing contradicting "global warming" can be posted.....thats truly shocking really!!

No. The Northwest Passage is not open. It is blocked in 3 places. It's a huge blockage of mixed concentrations of old ice at Alaska so won't melt much now but could easily move if wind and currents change. https://www.weather.gov/afc/ice It might ease to 1 blockage, given fair weather, but the Franklin Straight's old ice does not look much like giving way and some pleasure craft that had queued up for a week or two, waiting for it to melt, have started turning back as the usual navigable window starts to close and winter weather has started early (as per previous post). https://ice-glaces.ec.gc.ca/prods/WIS38CT/20180822180000_WIS38CT_0010195609.pdf https://saildogbark.com/2018/08/22/dogbark-turns-back/#more-1200 There is another pleasure craft that looks to have managed to trap itself for several days in the Franklin Straight but I have no detail. The Northern Route/Northwest Passage along northern Russia only opened last week, so that's pretty late and might not be open very long this year. You can just see a sliver of ice peeping out over Russia in the link above where you'd normally expect plain sailing. That and the first snows in Siberia hint at an early freeze up. There seems to be dispersed ice floating about here and there that flits in an out of charts. (The image in the previous post only seems to show 90%+ ice which hides the overall amount of ice as it seems to be generally more dispersed this year. The links in this one show lower concentrations which is rather more expansive - and too much if you are a sailing captain. It's worth noting that older ice is harder and does more damage!)

Estimate from the 06z is a finish of 17C before corrections, but could be 17.0 or 17.1C. No realistic chance of ending up below the 81-10 average at this stage. It's mainly been the maxima, keeping the CET up slightly higher than was forecast last week.

There's been fairly widepread snow in Idaho, Montana, Wyoming and even Colorado but NOAA hasn't caught up yet. There are, though, about a dozen new pixels below Canada if you look closely! Meteociel 6-hour forecast shows better where it has been snowing http://www.meteociel.fr/modeles/gfse_cartes.php?mode=16&ech=6&carte=1 Meteociel suggests winter stops teasing us and starts moving in properly in a couple of days.

Yes. If I wasn't so busy with work in the spring, I'd ideally take a week holiday in May while the UK weather sorts itself out, be here in peak summer (late May, June, July and occasionally early August), then another holiday in September when the weather's passed its best here but still good elsewhere.

I’m glad to took my uk holiday in early June. And no later than late July for most years, as it seems August is the worse month of summer to have a break in the UK. The weather seems to deteriorate back to low 20s and unsettled cloudy weather by the time we reach mid August. Even in the best summers like 2013, the weather was slowly going downhill by the latter part of August, in the London area. Glad I’m off to Spain in two weeks, to enjoy the warm and sunny days.

Overall we had an amazing summer, a bit too amazing for me at times I will admit. (Had to buy an AC unit to avoid melting lol) If we get a nice "Indian summer" that will be the icing on the cake for heat fans surely!

Aye, it's about watching reality rather than guessing with hypotheses....

it's been cold the past couple of days and my roast still went off when i forgot to put it in the oven

Not too bad a day today, mostly cloudy but the sun did make a few appearances and it still felt pleasant enough. Can’t complain really after probably the best summer since 1976 and September is looking rather dry and pleasant, if not hot.

Our Great Poplar, which is late into leaf and early to fall compared to other trees, was quite early last year. Leaves began to fall at the start of September and it was nearly bare at the start of October. It's currently about 10-15% golden brown and started dropping almost a week earlier this year. We had the first ripe blackberries in the first week of July and they are done now - too shrivelled and mushy to pick any more. What we've had have been smaller and made lovely intense jam. We already have ripe apples falling - though rather small. They are redder than normal - the reddest skins taste of strawberry/raspberry - and intensely sweet but quite acidic as well. They are already nice to eat but are a bit "pithy" after a bit of chewing - to be expected from smaller apples. The acidity and pithiness should fade into September when they more normally turn good for eating. We have a few plums but most still green. The early ripe ones are small but very sweet and more intense, with no acidity. I like them and I've never liked plums! Our pears were running 2 or 3 weeks early but were destroyed by wasps - lots of wasps - after the weekend of sharp showers that ended the drought. Our raspberries were good In June and early July but they got watered. We've had a second round come into flower a couple of weeks ago. I expected them to be green and shrivelled but a few are swelling and ripening so we look like getting a few in early September, which seems odd. Overall, fruit suggests summer ran anything from 2-4 weeks early and autumn leaf-fall seems to be a few weeks ahead encouraged by the recent couple of grey, dampish weeks and a couple of chilly days and nights. The trouble is last year's early seasonal changes brought a cold November, December, February and March (average Jan) that made for a very long winter. I hope the one month spring, and very early summer, and now, possibly, autumn does not mean an even longer winter in store but that is what I would guess at. By the way, cheeky_monkey - Meteociel is forecasting widespread snow for NW Canada at the weekend, although that may change. It seems rather early if it comes.

UKMO and GFS at T144: Pretty similar for next weekend. High pressure dominated,settled and warm for much of the country. GFS through to T240: I can't see what's not to like if an extension to summer is your thing.

The Ecm 00z looks a good run and ends beautifully..the Gfs 00z also looks summery through early september, there's plenty of high pressure and warmth, even some plume potential!☺

Thoroughly miserable all day here,rain from the moment I got up , this time next week i'll be in SE Spain ...can't wait

Ice always moves though whatever weather patter so nothing new there but I just think looking at the ice maps with concentration and compactness etc then Imo it seems we are heading to a total to last year. I must admit giving the highish compactness I thought we would see a bit more of a slow down than we seen so far but I'll be surprised if we got to 2007/16 levels but you never know with the Arctic. Speaking of the weather a huge cyclone could hit the basin quite widely soon although at this stage perhaps not very deep but if it sets up right it to could start forming the PV more widely but I do think the models and especially the ECM overdo cold temperatures in the medium range but one to watch.

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?

Some pictures from today...

Great day sledging with the boys. They were over the moon with it!!

Euro4 and ECM both wanting to go for a repeat performance for this evening from today, just a little accelerated. We see the streamer re-establish across Eastern-most parts of Essex running into Kent But then, a little quicker than today, we see the flow switch to more of an Easterly once again, pushing the formed precipitation westwards: So some heavier falls once again in the east but the chance of another covering into the London area by morning too. Perhaps a greater chance of a covering in East Anglia tonight as well. This is pretty unanimous across most hi-res models too: Thursday and Friday is then our next watchpoint - very uncertain even at this stage. Initially we have a warm front head North - this won't warm things up at the surface and will produce snow but it's tricky to tell just how much precipitation it will have on it. Here it is shown on the FAX charts: Most of the precipitation will be ahead of this first front. The latter frames of the Euro4 not that keen to introduce too much precipitation to our shores: However, it could be that it picks up more precipitation than expected as it comes across the channel and especially into the estuary with a strong flow in association with this. ECM and ARPEGE similar too: So some patchy outbreaks of snow I would expect through Thursday - we can all hope that it's a little more intense than currently modelled. ECM continues to bring in spells of snow through the day though with Eastern parts generally remaining drier. ARPEGE and ECM much keener on some more significant precipitation on Friday: As you can see, whilst the ARPEGE a little more keen on rain close to the coast, the ECM brings an all day snow event, which could be rather fun. So lots to keep an eye on for the rest of the week - Friday is the day with most potential beyond the next 12 hours and could give much of the region a very decent covering indeed. All to play for.

Amazing! Heaviest snow in years I’ve seen. Pic doesn’t do it justice . You were spot on mate. 1 inch in 35 mins!

I have to say, snow or no snow, this weather system has led to some incredible clouds and sunsets so far. Not sure if any of you have seen this tweet and picture of London from the police helicopter. Stunning.