Model Output Discussion 00z 19/07/13

[Gordon Webb]

preety much how id word it, cant rule out a chance of thunder as it will form in an area of high CAPE, but it will be infrequent if at all and more likely the further south you are, how did you deal with any storms earlier in the weem?

 

thanks for the concern

 

not  bad as the very worst of it didn't hit me head on just seem to skirt east and west of me which I managed to deal with reasonably and as for tonight going by what you say I'd might get the odd rumble with the rain so that is also manageable but the Carboot sale I was going to tomorrow might be in jeopardy

[Cecil Hogmanay Melchett]

Lovely ecm 0z with some very warm/hot air sourced from way to the south pushing north as we head through next week,as the trough parked to our west fills the azores high ridges in behind to kill off any storms associated with the plume wjich will mean a modification of the heat but reasonable temps in the low to mid 20's widely.

Whilst we cannot expect the clear blue skies of July as we head into August i think the washouts of the last few summers are not going to be repeated and im sure the vast majority of us sun lovers are especially delighted about that!

Obviously at this range the models cannot be 100% trusted but im starting to think that August might well turn out to be a reasonable month now.I hope so,the kids being off school deserve a good holiday period after years of dross.

[Methuselah]

And, as always, the Atlantic Hurricane Season might cause all sorts of havoc with mid- to long-term prospects...

[johnholmes]

And, as always, the Atlantic Hurricane Season might cause all sorts of havoc with mid- to long-term prospects...

 

that is quite often the case Pete, none of the longer range outputs, good as they are, and I am sure the 'hurricane' factor is in there, seem all that good at predicting the outcome for this area. This even when models show the upper air pattern producing such weather in the far western Atlantic and Caribbean areas.

odd really.

[Frosty.]

And, as always, the Atlantic Hurricane Season might cause all sorts of havoc with mid- to long-term prospects...

Yeah, it could send the jet well to the north with a lot more azores/euro anticyclonic spells for the uk & western europe, a hot mid to late august and very warm september..being of a positive disposition of course.

Edited July 27, 2013 by Frosty039

[Gael_Force]

It is tempting at this stage to claim the forecast from yesterday was all wrong, but this is still a developing situation.

 

The frontal boundary right now has a N-S orientation but upper winds are still SSW so everything is currently shifted further E. But the satellite presentation shows the boundary is forming a wave to the S and storms are still developing just to the E of it.

 

What I find particularly interesting is the huge storm cell that moved up the Channel overnight. It's appearance on satellite gives every impression of it being a meso-cyclone; the cirrus outflow is like a mini-hurricane, so it is so powerful it has created this. I don't recall seeing such a storm in a long time.

 

http://www.sat24.com/en/gb

 

 

Rain seems to be gathering to the S, so anything might happen as the day goes on.

 

The model longer term outlook brings us firmly into Atlantic air, at least for a time, but the prospect remains for another plume situation developing in a few days.

 

Fascinating weather!

 

Well Spotted!

 

Google translated discussion here.

 

http://translate.google.fr/translate?sl=fr&tl=en&prev=_t&hl=en&ie=UTF-8&u=http://www.keraunos.org/actualites/faits-marquants/2013/derecho-mcc-26-27-juillet-2013-orage-violent-rafales-gironde-charente-vienne-bordeaux-poitiers.html

[Frosty.]

Let's zoom in and take a look at this bad weather sweeping in at 3 hr intervals, as per the 6z, I really can't see there being much difference to the reality at this very short range. We are in for a soaking, there could be as much as 50 mm (2 inches) in the worst hit areas which means a strong risk of local flooding, along with the torrential rain there could be cracks of thunder as the mass of heavy rain spreads quickly north across the whole of the uk, the gfs has modelled this event very well over the last few days in my opinion. Looking at tomorrow, for scotland it's a washout with residual rain only slowly clearing in the afternoon but then followed by heavy showers, further south across northern england it will start sunny but heavy showers and storms will then break out widely, the driest part of the uk will probably be the southeast of england with warm sunny spells and temperatures in the mid 20's celsius. Monday and tuesday look unsettled everywhere with sunny intervals and heavy thundery showers, but then it turns drier, sunnier and hotter away from the far north and west with temperatures rocketing into the 80's and low 90's with a few scattered T-Storms developing and or a few severe storms rumbling up from france towards the southeast, but most of the disruptive rain next week looks more likely for the western and northern extremities of the BI but warm & humid with it, for england and wales, it's another scorcher on the way which will probably end with a BANG.

[OldMetMan]

Well Spotted!

 

Google translated discussion here.

 

http://translate.google.fr/translate?sl=fr&tl=en&prev=_t&hl=en&ie=UTF-8&u=http://www.keraunos.org/actualites/faits-marquants/2013/derecho-mcc-26-27-juillet-2013-orage-violent-rafales-gironde-charente-vienne-bordeaux-poitiers.html

Many thanks for that link, I was just amazed at the cloud pattern, clearly there must have been much damage with those wind gusts.

 

Imagine the chaos in London and the SE if that has been further NW in its track!

[Cecil Hogmanay Melchett]

GFS 12z looks OK

UKMO 12z has shifted the heat quite a bit east.

[Captain Shortwave]

GEM is epic, not only do you get the initial two day plume, it then builds heights over Scandinavia

 

Yes temperatures would drop back to around the 30C mark as uppers mixed to around 10-14C, but this is awesome if you want dry and very warm/hot weather.

Edited July 27, 2013 by Captain shortwave

[forecaster]

Whilst that is true, the ECM mean over the past 48hrs have often been much colder and yet the operational runs continue to predict a very hot S,ly plume. I think this is the 4th run in a row to do so. Now in my experience when this happens the operationals are what you take note of. This is even more apt considering the output from some of the other models.

 

The problem is that model run to run consistency does not correlate with accuracy. 

[Frosty.]

The ukmo 12z is still showing a hot & sultry spell later next week, especially the further south and east you are, with that hot continental drift comes a scattering of thunderstorms and the ukmo suggests a proper thundery breakdown next friday. The further north and west you are away from the hot zone, it's progressively less warm and less settled throughout next week on this run.

[Frosty.]

The GEFS 06z mean shows the brief cooler atlantic incursion through the first half of next week followed by the hot thundery plume pushing north from france, then the hot weather is gradually shunted away southeastwards and it becomes relatively less warm, more changeable and fresher, by next weekend it shows conditions becoming a bit more settled across the south with slightly higher pressure but cooler and more unsettled across central and northern areas.

Edited July 27, 2013 by Frosty039

[Captain Shortwave]

No beating round the bush, ECM is pretty poor compared to recent output from all models. Much more progressive with the Atlantic push

 

Very ordinary brief spell of warmth in the south (high twenties) and likely a breakdown of patchy rain.

Suppose with 16C close by you might squeeze 30C if it's sunny

Warmth all but gone by midday Friday.

Edited July 27, 2013 by Captain shortwave

[draztik]

ECM now unsure of the intense heat displayed in its earlier runs, the 12z has this outlook by Friday

[nick sussex]

No beating round the bush, ECM is pretty poor compared to recent output from all models. Much more progressive with the Atlantic push

 

Very ordinary brief spell of warmth in the south (high twenties) and likely a breakdown of patchy rain.

Suppose with 16C close by you might squeeze 30C if it's sunny

Yes its a big downgrade in the heat but so different from this mornings output that I'd wait till tomorrow before having a lot of faith in this operational run. Here theres not enough digging south of the jet to the west of Iberia and the heat heads ene. Plausible but I'd put this at one end of the more likely solutions, I still think a decent chance of some hotter weather effecting more especially the se but either way its looking like a brief hot up.

[Captain Shortwave]

Yes its a big downgrade in the heat but so different from this mornings output that I'd wait till tomorrow before having a lot of faith in this operational run. Here theres not enough digging south of the jet to the west of Iberia and the heat heads ene. Plausible but I'd put this at one end of the more likely solutions, I still think a decent chance of some hotter weather effecting more especially the se but either way its looking like a brief hot up.

Yeah that is true, the models have frequently pumped up the jet only to back down run or two later. Ironically at T168 the later stages of this run may look very good. Nope just a brief ridge then a slack southerly tracking jet.

The plume is still odds on, it's just whether it is a rather ordinary surge of tropical maritime air or a more substantial Spanish plume.

Edited July 27, 2013 by Captain shortwave

[Cloud 10]

Tonight's ECM operational run for the end of next week looks out of kilter compared

to previous runs,certainly when compared with its "shades and shorts" output from

yesterday!

 

yesterday..  today..

[Cheshire Freeze]

Tonight's ECM operational run for the end of next week looks out of kilter compared

to previous runs,certainly when compared with its "shades and shorts" output from

yesterday!

 

yesterday..ECM1-168.gif  today..ECM1-144.gif

 

It's what happens when you take charts at 168 hrs out as gospel.

[Man With Beard]

 

Tonight's ECM pushes the heat of Thursday and Friday away much quicker - perhaps maximum temperatures of 28C. However, this allows a transient HP cell to develop for the weekend and another near-miss of the 20C isotherm

 

 

 

If anything, tonight's output for the Wednesday-Friday period has become less clear. No record breaking runs; 28C-32C the highest likely. But no consensus at all about where things go after Thursday - a cold front will probably move in from the west, but no idea whether low pressure or high pressure will subsequently win out. It looks like we will be on a hot/cold divide, high pressure/low pressure divide and at the end of a bent jet. As a result, model output has become quite volatile. A 200 mile journey could mean an extremely different outcome. 

[Mark Parsons]

Tonight's ECM operational run for the end of next week looks out of kilter compared

to previous runs,certainly when compared with its "shades and shorts" output from

yesterday!

 

yesterday..ECM1-168.gif  today..ECM1-144.gif

I am always cautious when the models throw up such big swings, will be interesting to see what they churn out later!

[Frosty.]

The Ecm 12z is more progressive than the 00z and shunts the hot plume out of the way a day earlier but with a nice pressure rise building in behind it from the west, so not bad at all, it then becomes messy with flabby shallow troughs which indicates sunshine and showers as the main weather type but with respectable temperatures in the low to mid 20's celsius but this run lacks the wow factor of some recent ecm output but it's still much better than the dross we had last summer, and the plume could still be a record breaker as it's still in FI.

Edited July 27, 2013 by Frosty039

[nick sussex]

Yeah that is true, the models have frequently pumped up the jet only to back down run or two later. Ironically at T168 the later stages of this run may look very good.The plume is still odds on, it's just whether it is a rather ordinary surge of tropical maritime air or a more substantial Spanish plume.

To be honest CS the latter stages of the ECM look like another wild goose chase, it has another stab at bringing some hotter air north again but seems to be taking over the GFS mantle for solutions that need to be taken with a huge pinch of salt.In terms of the will it won't it plume the juries still out there, we best wait to the morning to see if this ECM operational run picks up support from the other models upto 144hrs.

[Captain Shortwave]

To be honest CS the latter stages of the ECM look like another wild goose chase, it has another stab at bringing some hotter air north again but seems to be taking over the GFS mantle for solutions that need to be taken with a huge pinch of salt.In terms of the will it won't it plume the juries still out there, we best wait to the morning to see if this ECM operational run picks up support from the other models upto 144hrs.

Ha I realised that after the next frame had come out. I'm already preparing my bed in the moaning thread due to having no storms and constant sea fog today. This run has not made me any happier

[summer blizzard]

Interestingly the ECWMF is the only model to bring back a settled spell even if it is day 8.