stodge

Rather depends on position and orientation of course. An intense HP centred just to the south of the UK can be quite clear and leave southern areas cold, frosty and foggy. Ideally, you want the mid latitude block to the east so cold SE'ly air is drawn in from a frigid continent but that tends often to be a cloudy airstream. An HP directly over the UK centred over central or northern England, while technically mid latitude, can often produce a cleaner solution but you do get areas of cloud trapped which circulate so you might get frost one night but not the next. The other aspect of my comment is that very cold scenarios can result from the HP over Iberia transferring NE into Scandinavia That is one of the three ways you get a Scandinavian HP - the other two are a) the Eurasian HP building west or WNW or b) the Arctic HP building south or South-South-West. The latter is extraordinarily rare, the former less so and you can have an intense HP (say 1050MB or higher) controlling our weather but centred over Finland and building a strong ridge westward. The famous 1962-63 winter cold spell started from the Iberian HP moving NE. If you look at the Archive charts on Meteociel, you can see how from 20-22 December, the Iberian HP moved NE over the British Isles and phased with an HP to the east to create an intense block which was centred to the east of Denmark on Christmas Eve and immediately retrogressed as a strong Arctic storm containing a portion of the PV moved ESE near the Pole. By the 27th, the HP was over Greenland and a frigid NE'ly was impacting on the British Isles and the rest is history. It's also worth noting where the core PV was at that time.

Morning all Without wanting to sugar coat it too much we are looking at 7-10 days of Atlantic-dominated weather from the middle of next week. We shouldn't be surprised or assume it's the end of winter or anything like that, We often get a milder spell at the beginning of December so this is just normal pattern shifting and changing. As to what happens before, we'll start seeing some tantalising offerings in the very far reaches of GFS FI before long - my money (and very nice money it is too) is on a pressure rise from the south and mid latitude blocking in the vicinity of the British Isles so not brilliant for fans of snow but fans of cold and especially frost and fog might get a decent spell under a classic winter inversion. The PV profile is very different to some more recent winters and that has to be of interest though my concern as always with those who want everything to happen in Greenland is the risk of the west based negative NAO which killed the 2010-11 winter at New Year. For now, the Atlantic will do its thing until it stops doing it and then we can see if we can get anything out of the next amplification.

Morning all Both GFS OP and UKMO suggest we may squeeze another 24-48 hours of chilly weather out of this spell but it's hard to see how it is extended much beyond this time next week. The problem is the ridging from the south pushing the LP to the NE seems stronger than the ridging from the north pushing the LP to the SE. GFS OP puts the LP over us or through southern Britain and UKMO might do the same but there's nothing for me showing a clear slide SE into Europe keeping the UK on the cold side of the fence. Looking at GFS OP, Parallel and Control all bring some form of PV into its usual place above NE Canada though interestingly at the very end of FI both Parallel and Control suggest any Atlantic-driven quasi-zonal flow could be short lived. We often see a milder Atlantic flow at the end of November and into December and with that you can see some very high temperatures under Foehn conditions in N Wales and the Moray Firth. I'm not seeing that this time. Parallel suggests HP building from the south will eventually displace the jet north and allow HP to set up close to or over the British Isles - a good old fashioned winter inversion, anyone? Control sends the PV energy back west over Canada which could allow for new height rises over Greenland into December which would interest many on here but I think that's a longer shot though the idea of a "cold" anticyclone dropping SE over the British Isles has a lot going for it if snow doesn't float your boat. We will have to endure 7-10 days of milder Atlantic-driven weather before the next opportunity for amplification comes along.

Oddly enough, I think it's a very good run. Yes, there are no screaming NE'lies with -20 uppers heading toward us but the one thing the GFS 06Z OP isn't is raging zonality. It's unsettled and often cold condition to the north of the British isles and plenty of rain for all parts (which is badly needed). Looking at the NH profile, the attempt to build the PV back over Greenland fails and the PV ends up right over the Pole which you don't see every day of the week. It's a plausible scenario going into December and the possibility of heights rebuilding is clearly there. Control and Parallel will no doubt look very different.

Afternoon all Just a couple of general observations/thoughts from me at this time: 1) The seeming inevitability of the west-based negative NAO which killed the 2010-11 winter stone dead just after Boxing Day always makes me think that those wanting a Greenland HP should be careful what they wish for. 2) We are also seeing the rise of pressure through Iberia as the Atlantic LP throws energy to the east. The only hope is if that ridging merges with the sinking Scandinavian HP (as shown on the 00Z Parallel) and re-enforces a Baltic/mid latitude HP. Otherwise, the ridging goes into central Europe and there we are. UKMO and GEM try to dissipate the energy east but neither ECM nor GFS seem that interested so it's an outsider for me at this time. 3) Looking to the outskirts of FI, the OP, Parallel and Control of the 06Z are all trying to rebuild the PV in its "normal" place and the PV dissipates out of Siberia. Now, this doesn't happen because of a cross-polar transfer as we often see from a Wave 1 attack on the PV from the Eurasian side but it just happens. 4) Many winters have a colder spell late November followed by a much milder interlude in early December (I think 15-18c is entirely possible in early December under Foehn type conditions in places N Wales and the Moray Firth) before a second colder spell in mid December and that's been hinted at by MetO in recent times. An evolution to a short-lived Atlantic spell followed by a renewed build of HP across the British Isles from the south or south west doesn't look unlikely. Mid December HP doesn't mean snow but can mean inversion with fog, frost and ice days.

Evening all Thought I would post this here rather than in the bearpit. My take on far FI is signs of the PV re-establishing so we aren't going to have three months of northern blocking and its' going to be a 7-10 day spell of below average temperatures before a reversion to something more "normal" but we'll see.

Afternoon all Well, it's been hard to believe some of the charts coming out in past days - I still wish we were seeing these four to six weeks down the road with a frigid Europe but there you go. The NH profiles are remarkable and are more reminiscent of a post-SSW phase than early winter when you would expect the PV to be ramping up and a stream of LP systems to be forming and deepening as they move NE on a powerful jet stream.

You have to remember many on here want snow while a small minority are happy with cold and don't care much about snow. As I often have to remind people, it's perfectly possible to get an ice day in London with an inversion - under fog the temperature is suppressed but not a flake of snow.

Evening all I don't normally think about winter until mid January but it's hard not to get wrapped up in what may be something we've not experienced for years - a decent spell of fog and frost and an inversion. I've always gone with the adage "the road to extremely cold starts from extremely mild" - cold spells often materialise as the air flow flips suddenly from south or south west to east or north east. The classic is the Azores HP moving NE from the SW approaches to Scandinavia. I don't know if we will see anything remarkable from this at this stage but, as others have said, it makes a change from some late autumn/early winter charts when a 12-hour transient N'ly at T+360 is all we saw.

Afternoon all I'm not wholly convinced at this time. I'm still seeing a lot of FI output dragging us back into a more zonal picture with HP sinking SE into Europe as the jet fires up. To be fair, the 06Z Parallel is a very different animal: Obviously a ridiculously long way away but in tune with some of the LRF signals. It should also be stressed none of this means three months of storm force easterlies and -20 850s for the UK (I'm fairly confident about that).

Very interesting weather over France and western Europe today which will impact on the UK tomorrow and Wednesday. http://vigilance.meteofrance.com/Bulletin.html?a=dept2B&b Red warnings over Corsica for a storm called "Adrian" which has developed to the east of Sardinia as part of the "Genoa Low" we often get when an HP builds over Scandinavia and we get a NE or E'ly flow over the southern British Isles. This segment of the LP is going to move north over Corsica and transit up eastern France, through Belgium and continue moving north through the North Sea to the east of the British Isles. It's not going to deepen much further (around 984MB) but it will lead to very strong winds and thunderstorms over Corsica and the south of France (hence the warning). For the UK it will probably only mean a spell of rain for eastern coastal counties tomorrow.

Evening all A rare early season visit from me but the ECM 12Z evolution tonight is fascinating. The Azores HP heads to New York for an early dose of Christmas shopping and the eastern Atlantic is left to LP forming to the NNW and coming SE across the British Isles and into NW Europe.

Afternoon all Completely FI and probably completely unsupported but: This would probably bring the colour back to your cheeks !! Chilly spell following: It won't happen though.

Morning all It is of course taking longer for the houses and the brickwork to release the heat so another warm night last night but the hope with today's rain and cooler air and some open windows we'll continue the return to normality. The weather though looks uninspiring - currently only light drizzle here in East London. but I note ther current NW radar showing some heavier rain in the Channel and some lively storms around Guernsey and Alderney.

Morning all General agreement (though not on the detail) of LP encroaching from the NW and crossing the British Isles through the second half of the weekend and into early next week so a disappointing few days after the spell we've enjoyed or endured (delete as appropriate) with temperatures closer to what we would expect and some of the wet stuff though not perhaps in the quantities some would like. After that (really from this time next week) it becomes much more confused - ECM settles us into an uninspiring westerly so average for all but GFS 00Z OP tries to build back in the Azores HP in various ways as does GEM but it's a little uncertain and half-hearted at this stage but obviously more runs are needed.

Looking at the latest Arpege and Hirlam models I'm not convinced the temperature record will go tomorrow or even Sunday. It looks as though the Spanish-Portuguese border will top at 46c but I don't see a 48 or 49c on offer though it may be someone somewhere gets very close.

Morning all :) Not sure about wading into this bad-tempered bear-pit today but I'm past caring. Some of the more outlandish 850HPA charts when this coming weekend was in low-res haven't materialised and we're back to the dilemma we've always had with two competing scenarios. In Scenario A the HP builds across the country then breaks from its parent Azores cell and meanders east into the North Sea or Scandinavia. This allows a S'ly or SE'ly feed of hot air to come from the Continent but pressure falls to the west and we get a thundery breakdown as the trough crosses the country easy to west before HP builds in again from the SW and the process re-starts. This is the traditional "three fine days and a storm" scenario with a period of building heat reaching a crescendo before storms and fresher air cause a re-set. In Scenario B the HP stays out to the west and never encroaches or the ridge builds across the UK but never breaks from the parent cell. This keeps us dry, warm or very warm but doesn't allow for the encroachment of hot air as the feed is from a N'ly or E'ly quarter across the south. This is our "fine summer spell" weather - lovely for the holidaymakers with onshore breezes but no exceptional heat or storms. There were and remain charts showing renewed northern blocking and retrogression and this would ruin August as we'd get the trough dropping into Scandinavia and a cool N'ly setting up down the North Sea. However, theses are far from certain but the truth is that old modern wives tale I've just made up: "if the core of the High be in the west neither heat nor storms will we get" "if the core of the High doth move east there'll be too much heat for man and beast" (I know, needs some work). Both GFS and GEM play to Scenario A but Scenario B has its supporters too keeping the heat well to the south. "

Here in lowland East London I'm showing 33c which is blisteringly hot. City Airport is 34c which is just off Heathrow - will anywhere reach 36c today, not sure ?

Afternoon all I don't see this concensus for heat at the end of next week and the beginning of the following week that some can see from the 06Z GEFS. First, it's low-res and FI when we're talking T+276 charts or beyond. That's not to say they can't or won't verify but nothing can be taken for granted at this stage. Looking through the members, yes, there are a number which bring the 20c 850HPA up to and across southern parts but there are a good number which don't. Yes, the heat builds to the south and through Iberia, no question, but it's far from clear to this observer that the hot air will reach our shores at this time. Yes, it might still be fine but more in the realms of very warm than very hot. As ever, more runs are needed.

Late morning all :) One of the runs yesterday showed a classic retrogressing HP into Greenland - a beautiful thing though not for fans of heat as the NNE air flow introduced would cool things down significantly. The modelling of next weekend's push of heat remains from clear - the 06Z OP looks to be heading down a very toasty route with the 20c 850HPA reaching the SW on Monday 7th: http://modeles.meteociel.fr/modeles/gfs/runs/2018072606/gfs-1-276.png?6 Two points though a) the heat keeps getting delayed and hasn't made it into low-res and b) there remains considerable variation (compare with a relatively cooler 00Z). If you want heat, the HP has to disrupt east to bring up the hot air from Iberia - if it retreats west, the flow will be from the N or NW and the hot air stays to the south. The former offers much more storm potential, the latter would likely see a quieter transition to cooler conditions.

Evening all Have to say it looks like a step or two back from the heat-topia of earlier runs. Thursday and Friday this week look hot for the SE and certainly 33c looks likely but a significant breakdown through the weekend with much cooler air pulling temperatures back to a much more agreeable 25c or so. The end of next week remains in low-res so forecasting very difficult - the signs for a new thrust of heat north from Africa and Spain across France are clear but from previously looking as though Friday 3rd would be the climax of the heat with the 20c 850 crossing England, it now seems to be Sunday 5th and Monday 6th which could be the hottest days but the 20c 850 doesn't quite make it before the Atlantic pushes cooler air back in. This is from the 12Z GFS OP - the 06Z parallel was underwhelming but the 12Z Control kept the heat through to the end of the week after next especially, oddly enough, in the SW. More runs are needed but I don't see records in danger just yet.

I certainly think we could have some short-term pain for some longer-term gain if the longer-term signals are correct and the pattern shifts to HP developing to the east rather than the SW or NW. As the Azores HP slackens and LP moves in, a longer or shorter spell of more unsettled conditions looks feasible before the new pattern establishes but that might mean LP sitting over the British Isles with the attendant poor conditions.

Afternoon all The 06Z Parallel is also pushing the idea of a breakdown from the NW from mid month Parallel FI not one for the sun-worshippers, almost autumnal with LP in charge. The 06Z OP tries to build heights to the far north which pushes the jet back south and pulls the Azores HP back SW. Well, maybe, but I'm not convinced and it's all FI for now but certainly perhaps a sign the light at the end of the tunnel is the Breakdown Express.

Morning all :) Apologies for invading this thread but Mrs Stodge and I were touring round southern Ireland last week and it was absolutely phenomenally magnificently glorious. A noticeable Easterly wind in Dublin and Waterford and along the southern coast tempered the weather slightly in the early part of last week but we got to Killarney last Tuesday and enjoyed two fantastic days in Kerry. Slightly hazy and cloud came in one evening to spoil the sunset over the Lakes but the temperatures were in the mid 20s so very pleasant with low humidity. From Killarney we drove north to Galway and spent two days in what I can now describe as Ireland's Oven. The Cliffs of Moher were scorchingly hot with temperatures pushing above 30c and a hotel room in central Galway without air conditioning almost unbearable. In Connemara last Thursday we were over 30c but I think Shannon Airport hit 32c on Thursday as well. Driving back across to Dublin, the Midlands were warm but back on the coast the refreshing breeze made for a pleasant evening strolling around Temple Bar. Fascinating to see the synoptics favouring the heat for the west so strongly and no surprise but the thermal gradient even on such a small land mass was interesting. Galway and Connacht were much hotter than Dublin and Leinster. While the temperature record was set at Kilkenny, I think a station like Shannon Airport, Athenry or Mullingar must be favoured next time. A beautiful country and a wonderful week but a sense we can never go back as it will never be that good again.

Morning all A return for the morning medium term analysis from me. After a synoptically fascinating late winter and spring with the latter starting with an incredibly cold spell and ending with one of the warmest and sunniest May months for decades, where does summer go from here ? It's actually quite cool and uninspiring in London Town this evening but where will we be on or around Midsummer (at least in solstice terms) ?: ECM 00Z at T+240 (Friday June 22nd): A typical summer chart for NW Europe with the Azores HP ridging strongly NE and a weak jet held well to the north. Decent conditions - warm but not hot with a gentle NW'ly flow and always the risk of damper and murkier conditions on western coasts and hills. GEM 00Z OP at the same time: Much more solidly anticyclonic with the ridge over Ireland and NW Britain so a cooling NE'ly breeze for southern and eastern areas meaning it's pleasant rather than oppressively hot. GFS 00Z OP at the same time: The Azores ridge has a more easterly tilt so crosses southern parts with most of the British Isles covered by a balmy WSW'ly flow. Fine and warm especially in the south but cloudier and mistier to western coasts and hills. GFS 00Z Parallel at the same time: Not hugely different from the OP. GFS Control at the same time: Closer to the GEM. In summary, it's quite settled vs very settled as we move to the end of next week and those attending the last couple of days of Ascot should be fine in their finery (so to speak) with comfortable to warm temperatures but nothing excessively hot or humid on offer. Dry for many if not most but western coasts always vulnerable to a muggier Atlantic and some drizzle and low cloud at times, It's not very interesting synoptically in all honesty but it's summer weather - beyond that the question is whether the ridge relaxes back SW or cuts away to the NE and that might be of much more interest.