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

[SMU]

Things becoming 'interesting' overnight on the 00z UKMO & ECM-

Without being accused of 'sensationalism' there really are records tumbling daily across the globe -

June - hottest June on Record with 3 notable anomalous heat expanses across the globe - 

Note the heat to our south ( more so South & East )

In terms of rankings for monthly values you can see the concentrations-

Most of central Europe Rank 1 warmest on record.

-So we have a heat anomaly to our south circa +4/5C

- A persistent -NAO pattern that will promote stationary blocking in which a deep southerly flow may well develop.

The risk of the UK breaking its all time record is not 'HIGH' but probably significantly higher than usual....

This time around we don't get the chilly airmass ahead of the hot uppers - A few days of +20C uppers & slack SE winds would throw us a chance...

 

[tight isobar]

4 minutes ago, Steve Murr said:

Things becoming 'interesting' overnight on the 00z UKMO & ECM-

Without being accused of 'sensationalism' there really are records tumbling daily across the globe -

June - hottest June on Record with 3 notable anomalous heat expanses across the globe - 

Note the heat to our south ( more so South & East )

In terms of rankings for monthly values you can see the concentrations-

Most of central Europe Rank 1 warmest on record.

-So we have a heat anomaly to our south circa +4/5C

- A persistent -NAO pattern that will promote stationary blocking in which a deep southerly flow may well develop.

The risk of the UK breaking its all time record is not 'HIGH' but probably significantly higher than usual....

This time around we don't get the chilly airmass ahead of the hot uppers - A few days of +20C uppers & slack SE winds would throw us a chance...

 

no sensationalism at all Steve. ..

an accurate account. ..

the UK  record  looking  under increased threat  through  next  week...

 

*we are going to hell*..

[Summer Sun]

14 minutes ago, Osca31 said:

I hope notAren’t these accumulated rainfall totals for a certain period tho ,whereas the temp charts are from single days?

Correct the 24hr periods for early next week

Edited July 17, 2019 by Summer Sun

[mb018538]

The ecm op run well above the mean and sitting outside the ensemble spread again as you’d expect.....but what’s with noting is that the mean now goes above 15c - a day or two ago it sat at 12/13c.....perhaps indications that the heat is the more favoured option as we draw into the reliable. Fascinating watching!

[Catacol]

On 15/07/2019 at 19:48, Singularity said:

Quality from Tams as usual - atmospheric disconnect from the ocean doesn’t always work against us

 

Yes - clearly true. I wonder at the number of times in recent times that we have noted a "disconnect" between the oceanic signal and the atmospheric response. I haven't charted it on a spreadsheet or anything like that....but anecdotally we have described a disconnected state often. Genuine question - is our understanding/modelling of the "connect" between ocean/atmosphere too simplistic in terms of the current GSDM interpretation, or are conditions becoming generally less predictable in our modern climate context? Where, in all this, do the changing conditions in the arctic sit? 

[Frosty.]

There's good support from the GEFS 0z mean for a hot spell developing next week, at least across southern uk, there is even a chance of 38c 100f on one of the most extreme members and several into the mid 30's celsius range...I would be very surprised now if the south / southeast doesn't become very hot and humid next week!

Edited July 17, 2019 by Jon Snow

[Singularity]

  

Here's GEM providing an example of the flatter solution that could sweep the heat away in a different way to how FV3 keeps doing it - but interestingly, it doesn't fullu succeed on this run, with a push back of the heat dome on Friday.

My comments on the FV3 model physics aren't entirely based on the divergence of its solution; since it was introduced, I've noticed that for a given broad-scale setup, it really does tend to do different things with the energy distribution within the troughs. I can't think of many times those differences have proved nearer to the mark, but there are still enough that I'm not going to go and throw its runs out the window.

It's really something that FV3 sweeps the intense heat fully out of France by Thursday afternoon, while the other models are building to increasingly extreme levels there, with varying degrees of extension across the UK.

[Frosty.]

I should also add that there are quite a few GEFS 0z members that don't show any heat as such next week, some show a fresher NWly breeze..just for balance!!!!!!!!!

[Singularity]

6 minutes ago, Catacol said:

Yes - clearly true. I wonder at the number of times in recent times that we have noted a "disconnect" between the oceanic signal and the atmospheric response. I haven't charted it on a spreadsheet or anything like that....but anecdotally we have described a disconnected state often. Genuine question - is our understanding/modelling of the "connect" between ocean/atmosphere too simplistic in terms of the current GSDM interpretation, or are conditions becoming generally less predictable in our modern climate context? Where, in all this, do the changing conditions in the arctic sit? 

Hi Catacol . Good points and great question!

Away from the GSDM, I believe that understanding/modelling is suffering a bit for being heavily rooted in our past experience when the climate wasn't been destabilised so much.

A possible explanation that warmer SSTs permit more in the way of atypical tropical convection flareups, reducing the success rate of assumptions and parameterisations that were once reasonably effective.

The GSDM actually provides a means to find ways around this if interpreted correctly, thanks to the fact that it depicts not only AAM anomalies, but tendencies with time that can reveal atmospheric cycles of Nino or Nina-like state independently of whether ENSO is aligned to them or not.

 

p.s. don't bother with GEFS-based GWO/AAM plots; they've gone off the rails again. Not sure why this keeps happening. A few months back they were off the top of the scale, now they're off the bottom! This must just be a processing error from the model output though; if it wasn't, the weather patterns from GEFS would be persistently heading in very different directions to other modelling.

 

[Methuselah]

I'm guessing here but, based on our species's problems with scientific enquiry, if what many call a 'disconnect between ocean and atmosphere' is actually a glaring hole in our understanding?

As fast as one hole is 'plugged' another one rears its head?

Meanwhile, back on Terra Firma, many of us might even see some much-needed rainfall, later this week?

   

[Frosty.]

I think balance is very important regarding next week, there is support for hot weather, especially for the s / se but there is also support for no hot weather as such next week so certainly nothing is in the bag as of yet!

[Connor Bailey Degnan]

Gfs operational sticking to its guns now, gfs legacy similar, think we can be safe to say itll be very warm/hot across eastern and southern areas on Monday and Tuesday but then its anyones guess. I'd take a stab at the ecm and UKMO backtracking towards gfs solution.

[Djdazzle]

4 minutes ago, Connor Bailey Degnan said:

Gfs operational sticking to its guns now, gfs legacy similar, think we can be safe to say itll be very warm/hot across eastern and southern areas on Monday and Tuesday but then its anyones guess. I'd take a stab at the ecm and UKMO backtracking towards gfs solution.

Actually the 6z has moved slightly more towards the ECM / UKMO. I’d never back GFS after its past disasters!

[Downpour]

1 hour ago, mb018538 said:

The ecm op run well above the mean and sitting outside the ensemble spread again as you’d expect.....but what’s with noting is that the mean now goes above 15c - a day or two ago it sat at 12/13c.....perhaps indications that the heat is the more favoured option as we draw into the reliable. Fascinating watching!

Yes, it is rather odd behaviour from the ECM op run, sending out consecutive hot outliers. But, as you imply, the trend might well be the friend of those hunting for heat. 

[mb018538]

GFS doesn’t want to know again - turning very unsettled and forcing the trough straight through like the 00z op. Probably a cool and unsettled outlier again to be honest, looks quite extreme.

[Downpour]

At work so short of time, did this morning's GFS op go with the ECM (I assume so by the posts above)? 

[Methuselah]

Tuesday could be quite hot, at least darn 'ere in ver sarfeast'? Unless things have changed since the 00Z, this is also the point where the ensembles all go haywire...

   

 

[shaky]

29 minutes ago, Djdazzle said:

Actually the 6z has moved slightly more towards the ECM / UKMO. I’d never back GFS after its past disasters!

Yup was gona say the same!!looks like its moved towards ecm around 120 hours!!i think its gone be one of those embarrassing crawl backs towards the euros once again!

[Frosty.]

Certainly the Ecm 0z ensemble mean hasn't downgraded our chances of a very warm / hot spell next week, at least across southern uk but even scotland would become preety warm too..the s / se could be looking at a scorcher, into the 30's celsius!

[Captain Shortwave]

It seems very subtle but the major difference the GFS has occurs around the day 4/5 mark where the ridge towards Greenland dissipates allowing a stronger jet stream to rush east through the Atlantic. Compare this to the ECM/UKMO which maintain this feature which allows the downstream amplification to occur, building that Euro high as a result, with most of the UK under its influence and the associated potential heat it could bring.

The ECM May be an outlier, but has support from the UKMO out to day 6.

Edited July 17, 2019 by Captain Shortwave

[Methuselah]

Well, the GFS 06Z certainly ends on a rather idiosyncratic (for want of a better word?) note. Is one of our closest teleconnections, the Arctic Oscillation, threatening to flex its muscles? I do hope not!

  

[Frosty.]

Certainly the Gem 0z ends on a distinctly hot and sweaty note down south..phew!!!

Edited July 17, 2019 by Jon Snow

[MATTWOLVES 3]

Just to take a look at some of the main models out to day 6 regarding next week's heat... Looks like a warm up for sure... How warm and how long is another question!! Looking at the next few days we have some rain later today, clearing tomorrow... Thursday looking mainly fine in the midlands. We have periods of rain pushing NE on Friday, this clearing to sunny spells and showers for saturday... The south looking to become increasingly warm and settled on Sunday. Next week is where the fun and games start. The heat may build to extreme proportions in places, will it be displaced by cooler conditions from the NW, or remain in situ for a while longer... Not a done deal from a long stretch at this stage.... Expect upgrades and downgrades over the coming days!!! As per winter set up really... 

Edited July 17, 2019 by Mattwolves

[Singularity]

       

 

I can't see any FV3-style displacement of the heat in these clusters for D7 & D8 respectively, but it looks like just over 15% do so using the main Atlantic trough instead on D7, with nearly 22% having done so in that way by D8.

Aside from that, a strong heatwave signal for W. Europe and S. UK, with the operational in the majority cluster.

As long as FV3 keeps following a very different route though, it's hard to have much confidence in conditions past Monday.

[weirpig]

Some stonking  runs in there    and some stinkers     Opp and Control  really going off on one    both sides of the extreme