Model output discussion - first hot, thundery plume of the summer

[Guest]

Wow, just wow. The back of the ECM builds a significant heatwave across Western Europe, once again temps into the 40s in central France. No plume to speak of as there’s no cut-off but some very hot air drawn in towards to the UK with 850’s into the low twenties once again but this time no nasty easterly undercut.

[Dangerous55019]

Evening everyone 
I just thought I'd shove my two peneth worth into this MOD thread this evening with the weekly anomalies from the CFS.

Week one does to my unprofessional eyes look potentially plumey and thundery... But as always with these scenarios we're gonna have to watch the situation very closely. 
Week two looks potentially hot! with a slack easterly(?) airflow as high pressure is centred more or less right over the top of us.
Week three looks like more of the same high pressure fest, but due to a slight re-positioning of the high, it could drag up some very warm air from the south.
And as for week number four... Well... Just make of that what you will! Lol 

As always, this is the low resolution CFS, so please take these charts with a gritter full of salt, but hey, they are a handy guide. 

[Mike Poole]

I've been absent for a couple of days (cricket - you know!) but it seems that there has been a move in the model output generally towards more potential for heat and plumes.  It's consistent with the latest guidance from GloSea5 for sure, and is interesting to see.  I've not yet had time to fully digest the 12z output today, but the ECM mean surely looks OK:

Edited July 15, 2019 by Mike Poole

[Frosty.]

Great Ecm 12z ensemble mean longer term, especially across southern uk the further s / se the better for increasing warmth / heat..and sunshine, it would never look as extreme as the operational but it still compliments it!!!

Edited July 15, 2019 by Jon Snow

[Methuselah]

2 minutes ago, Mike Poole said:

I've been absent for a couple of days (cricket - you know!) but it seems that there has been a move in the model output generally towards more potential for heat and plumes.  It's consistent with the latest guidance from GloSea5 for sure, and is interesting to see.  I've not yet had time to fully digest the 12z output today, but the ECM mean surely looks OK:

And, with any luck, and in the absence of any pesky Greenland HP (hopefully not famous last words?) the coming push of hot air will win out; we've been on the cusp, of all that European heat, for far too long, methinks!

[danm]

1 hour ago, Captain Shortwave said:

Hmm no real plume set up there (lack of low pressure towards the Bay of Biscay). However the ECM run is getting close to the sort of set up we experienced in August 2003 with that heat dome expanding northwards. Probably overplayed given the other output though and the thought of glancing blows of very warm/hot weather is more realistic.

Would prefer this to a plume personally as it could make any heat last longer. Plumes are often short lived.

[mb018538]

I think more nailed on is our friends in the near continent going seriously into the furnace again in just over a weeks time. Whether we join the party or not is still open to debate, by Spain and France could be looking at another round of 40-45c temperatures. Incredible so soon after the last heatwave.

[Singularity]

Reviewing the ECM D10 for what it's worth, it's actually a properly dangerous-looking setup to me, for western Europe.

Although that little cut-off low escapes from Iberia, it's very shallow and doesn't look capable of deepening soon enough to swipe the heat away from the S. half of the UK. Meanwhile, the heat dome to the south has a bit of a heat low across Iberia and the Bay of Biscay, north of which some shallow ridging would probably develop, trapping the heat in place for longer.

The Atlantic ridge also looks to prevent another Atlantic trough from pushing for a breakdown within at least a few days.

While it's inevitably got a low chance of being close to the actual outcome, the mere existence of such solutions in the modelling is a useful indicator that what's taking place Thu/Fri through Sun/Mon is likely to be building a foundation conducive to some manner of high-calibre W. European heatwave next week.

It just remains to be seen whether it'll be a skyscraper or a flat that's built onto the foundation .

[Don]

4 minutes ago, mb018538 said:

Whether we join the party or not is still open to debate, by Spain and France could be looking at another round of 40-45c temperatures. Incredible so soon after the last heatwave.

Heatwaves are becoming more and more frequent, so not really a surprise and only a matter of time before the UK is in the firing line!

[SLEETY]

amazing how many times the UK just misses out on extreme heat or cold for that matter with it staying on the other side of the channel in France etc,maybe just once we will hit the jackpot

[Man With Beard]

1 hour ago, northwestsnow said:

Hotter still by day 10 !!

Jeez i'm of work end of July i hope it sticks around!!

ECM temperature charts for D9/D10 are a couple of degrees higher than the June 29th ones... Still a long way out though. If these charts are showing at D6/D7 then time to start considering them more seriously. However, the ensembles this morning did not paint tonight's run as an outlier by any means, and tonight's mean still looks hot especially in the south. 

[Frosty.]

The cfs is looking nae bad in late August and even better in late January!!!!!!

[Djdazzle]

Back to models - a really positive day overall. Hoping the overnight runs build on it. I’d say 25% chance of significant heat next week.

Edited July 15, 2019 by Mapantz

[Downpour]

1 hour ago, danm said:

Would prefer this to a plume personally as it could make any heat last longer. Plumes are often short lived.

Raging heat, humidity and instability not my cup of tea although accept other members relish it. My interpretation of the models is that France will go into the cooker again but S/E borrowing the heat, with several warm days possible. Think a full blown heatwave is odds against, but in the mix certainly. 

[Mapantz]

Quote

I’d like to think the mods just haven’t spotted it yet.

I'm here, at just the right time as well. 

[knocker]

The North Atlantic 500mb and surface analysis for midnight.

Quite a clear start to the day in most places with the odd mist patch around but frequent showers will quickly spread into N. Ireland and Scotland courtesy of a trough embedded in the circulation of the low south of Iceland. And then showers will also pop up in Wales, the midlands and East Anglia as the sun gets to work on a generally warm day.

The showers will fizzle out this evening leaving a clear night for most with again the odd mist/fog patch forming. But to the west a new wave has tracked north east and merged with the low south of Iceland and the associated fronts bring cloud and rain into N Ireland and western Scotland by dawn

The wave completes the merger with the main low on Wednesday and the fronts continue to edge south east across the country bringing rain, with some heavy pulses, into northern and western regions whilst the south and south east remain dry, sunny and warm with a marked NW/SE temp contrast

Overnight and through Thursday the occlusion and band of rain continue south east clearing in the early afternoon leaving sunny intervals and showers in their wake. But things are gearing up to the south west with a new trough appearing on the scene.

By Friday the new trough has also merged with the main low and the surface wave and associated fronts are tracking north east across the country bringing with them rain and quite gusty winds.

The front(s) and rain will clear into the North Sea around midday on Saturday and there could well be some thundery showers in their wake with the odd trough i the circulation.

[knocker]

So according to the gfs the NH profile at T144 is thus with some frontal rain encroaching western regions

Twenty four hours later a new upper trough has tracked east creating a new and elongated positively tilted trough in mid atlantic which starts to stir the subtropical high in the vicinity of the UK where showery rain still effects the NW Temps creeping a tad above average

By T192 the trough is becoming more neutrally aligned as this continues to promote the ridging of the subtropical high. Still some showery stuff effecting the far north but generally a dry and quite warm day but only south of the border

 

 

 

Edited July 16, 2019 by knocker

[Methuselah]

Well, not being one to get over-excited, here's a frame from the GFS 00Z:

   

And so, on to the mighty ensembles: and WHAT A STONKER!

   

    

As I've been 'expecting' (or, rather, hoping for!) a wholesale northward-migration of the European heat, for some weeks now, I guess I'm happy that it might actually happen...But, I do have a question: would I be right in thinking that, as the Southern Oscillation signal approaches neutrality, we in the UK, become more subject to the vagaries of local phenomena than earlier in the Summer?

Also, when is the QBO expected to turn easterly? Thanks in advance...

[mb018538]

ECM blows the Atlantic low up much more than GFS today, with the net result being that it pushes through and prevents the ridge from building in like the GFS.



You can see from a comparison of the big 3 at 144 hours that the ECM has the low much closer to the UK by day 6, with less of a ridge being thrown up ahead of it. It's a perfectly plausible solution, just perhaps not the one that many want. This is the key area to keep an eye on. If the ridge build in ahead of the low, we get heat. If the low dominates, it's a glancing warm blow to the SE and more unsettled towards the NW. 

[knocker]

The ecm T144 > 192  The difference from the gfs is of course the alignment of the upper trough in the Atlantic which slowly becomes positively tilted and thus does not initiate subtropical ridging to any great degree. Fronts crossing the country during the three days so periods of rain, showers and sunny intervals with the south east, as usual in this pattern, receiving the best of the weather. The detail is of course still subject to change

[Singularity]

ECM progresses the trough as if it was November... so, I find it hard to take seriously until it and when other models align with it.

As often, UKMO occupies the halfway house position that feels easiest to believe.

[knocker]

The EPS mean anomaly this morning pretty much as it's been indicating for a while. And NOAA not adverse to this

[Frosty.]

The Ecm 0z ensemble mean turns into a stonker next week with high temps and sunshine, at least for southern uk, the highest temps further s / se!!

Edited July 16, 2019 by Jon Snow

[shaky]

Anyone else notice that when the gfs looks good for hot weather then the ecm goes the other way around and dont look as good!!when ecm looks good then gfs does not lol!!ukmo always looks a halfway house!!maybe its just me!

[mountain shadow]

25 minutes ago, Jon Snow said:

The Ecm 0z ensemble mean turns into a stonker next week with high temps and sunshine, at least for southern uk, the highest temps further s / se!!

Is that really a stonking mean? Even for the South East?

There would be plenty heavy showers around and perhaps even longer spells of rain.