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

[knocker]

Over the next three days the gfs has the upper trough to the west continuing to realign as it is 'fed' by energy exiting the north east seaboard until it eventually deconstructs with a trough over the UK. This of course amplifies the subtropical high further to the east and thus the WAA as well. All of this is still a long way from a done deal as the models get to grips with the energy distribution

 

[mb018538]

1 hour ago, northwestsnow said:

UKMO looks very warm/hot 120-144, esp for the south.

GFS still flapping around like Rod Hull and Emu.

Wouldn't worry about the GFS OP this morning @northwestsnow, big stinking cold outlier. Still a lot of GFS members going for the plume - perhaps starting to develop like the one in late June. UKMO and GEM look very hot for a time, but until the ensembles tighten up and we get some agreement it could still go either way.

[northwestsnow]

EC looks more UKMo than GFS at 144-

Its warm/very warm but not sure how this run will pan out..

[northwestsnow]

Oooooo lala !!

EC takes us into the furnace next week with uppers of 20 across the south- will look forward to reading the maxima on the 168!

I will take a stab at 31 in the SE of England..

Edited July 17, 2019 by northwestsnow

[northwestsnow]

And the one man commentary continues lol..

Day 8 is just silly , the uppers are even higher, lol again.

34/35 deg perhaps??

[mb018538]

Well ECM is bonkers and brings in 22c uppers again, much like the 12z. This will either be epic or a massive fail. Trying not to hype this up...

[northwestsnow]

1 minute ago, mb018538 said:

Well ECM is bonkers and brings in 22c uppers again, much like the 12z. This will either be epic or a massive fail. Trying not to hype this up...

Ahem, uppers are TWENTY-THREE..

[mb018538]

The main difference (and a huge one at that) with the GFS vs ECM today:



Notice how ECM creates a cut off upper low down towards Biscay - which helps to draw the really hot uppers out of Spain & France and send them our way. GFS just ploughs the trough straight through instead. Features such as this are tricky to model reliably at such long range, so it's no surprise we have lots of variation at this range.

[northwestsnow]

8 minutes ago, mb018538 said:

The main difference (and a huge one at that) with the GFS vs ECM today:



Notice how ECM creates a cut off upper low down towards Biscay - which helps to draw the really hot uppers out of Spain & France and send them our way. GFS just ploughs the trough straight through instead. Features such as this are tricky to model reliably at such long range, so it's no surprise we have lots of variation at this range.

I agree, from my perspective its as exciting seeing these extreme uppers in summer as it would be if they were -22 uppers in Winter.

We are edging into the reliable now, if the EC output remains consistent then confidence will grow , i think we will see a plume, still not sure it won't be a 2/3 day event.Maybe CS will be able to tell us what sort of temps EC det is progging, the day 8 could be really really hot, mid /late July is a good time for some high temps i would say.

edit or MWB perhaps wrt the temps..

Edited July 17, 2019 by northwestsnow

[Man With Beard]

10 minutes ago, northwestsnow said:

Ahem, uppers are TWENTY-THREE..

I believe this is now 4 out of the last 5 runs from the ECM that bring the 20C uppers line to the south coast. The UKMO has been in agreement with the general progression up to D6. Here we go again folks... 

[northwestsnow]

1 minute ago, Man With Beard said:

I believe this is now 4 out of the last 5 runs from the ECM that bring the 20C uppers line to the south coast. The UKMO has been in agreement with the general progression up to D6. Here we go again folks... 

Yep, EC with 2 consecutive DET runs bringing the furnace , perhaps even more interesting another run cancelling any breakdown.. 

The latter charts on EC would surely have the July record under threat?

[knocker]

Interesting ecm next week in the unreliable time frame

It has the upper trough and the energy battling against the ridge so that eventually the trough disrupts whuch allows the hot airmass in the south to move over the south of the country

The end result being the stabilizing of the high cell to the SE

 

 

 

Edited July 17, 2019 by knocker

[Singularity]

Well, IMO, that ECM run is how 40*C gets reached in London or thereabouts - unless thunderstorms kick in of course.

Raw numbers should be of interest - could well  be higher than the 37 max of yesterday’s 12z.

 

So what of FV3? It seems at odds with the GEFS (which are still old core) so that’s intriguing. For reasons we can only imagine, the new core is causing FV3 to put a lot more into the arm of the jet heading ESE into Iberia than the one heading past the W/NW of the UK Tue-Wed. This spins up a low to our S that quickly lifts N and interacts with the Atlantic trough.

This appears as if it might be a major disagreement driven more by model physics than uncertainty in trough behaviour. If so, it’s going to be a huge deal which side is victorious; the old gang or the half-new guy?

Edited July 17, 2019 by Singularity

[knocker]

Here you go. An ideal chart for the many on here who are in receipt of a stipend from the southern tourist board

[Methuselah]

48 minutes ago, mb018538 said:

The main difference (and a huge one at that) with the GFS vs ECM today:



Notice how ECM creates a cut off upper low down towards Biscay - which helps to draw the really hot uppers out of Spain & France and send them our way. GFS just ploughs the trough straight through instead. Features such as this are tricky to model reliably at such long range, so it's no surprise we have lots of variation at this range.

There is also some huge disagreement within the GEFS ensemble-members themselves: about a 20C (T850) disparity between the op and control, with the op being very-much at the cold end of the pack?

   

   

So, I suggest we are nae much nearer a resolution today, than we were at this time yesterday: heat of some sort arrives on the 23rd, and then all bets are off...?

Edited July 17, 2019 by Ed Stone

[Guest]

Well once again GFS and ECM Ops couldn’t be more different. ECM is again staggering and would deliver 100f in the south east. 

[knocker]

7 minutes ago, Singularity said:

This is a major disagreement driven more by model physics than uncertainty in trough behaviour. It’s going to be a huge deal which side is victorious; the old gang or the half-new guy?

Could you expand on that please because I'm sure I'm not the only one who is not well up on model physics. And who are the old gang. The ecm had a major upgrade last year?

I ask because to me, and I'm a million miles away from being very knowledgeable, it looks like uncertainty of trough behavior and energy distribution

[Singularity]

11 minutes ago, knocker said:

Could you expand on that please because I'm sure I'm not the only one who is not well up on model physics. And who are the old gang. The ecm had a major upgrade last year?

I ask because to me, and I'm a million miles away from being very knowledgeable, it looks like uncertainty of trough behavior and energy distribution

Good point regarding ECM, I suppose older gang is more accurate (grouped with UKMO and GEFS).

I think GEFS are due a long-awaited upgrade within the next year. Perhaps? Not 100% on that.

 

As for it being model physics, this is a deduction based on the existence of such a stark disagreement between FV3 and the other modelling, with not many overlapping ensemble members.

Not yet checked the individual EPS mind; some presumption there on my part, I will admit.

The quick breakdown GEFS solutions are mostly driven by the Atlantic trough being too positively tilted as we saw with yesterday’s ECM 00z. This remains a very possible derailment method.

I’m not entirely keen on seeing multiple days in the mid-30s or so such as today’s ECM 00z sets in motion, so it’s reassuring to see this scope for something briefer (albeit probably less extreme for the peak max if so).

Edited July 17, 2019 by Singularity

[Man With Beard]

23 minutes ago, knocker said:

Here you go. An ideal chart for the many on here who are in receipt of a stipend from the southern tourist board

35C the day before and the day after, too.

Of course we saw how easily the surface heat was modified on the models last month, so this is all still FI. Though, with the bulk of the ridging coming from the south rather than a build from the north west this time, I don't think we'd miss out on the exceptional temperatures if the current position remains fairly similar. 

[knocker]

26 minutes ago, Singularity said:

Good point regarding ECM, I suppose older gang is more accurate (grouped with UKMO and GEFS).

I think GEFS are due a long-awaited upgrade within the next year. Perhaps? Not 100% on that.

 

As for it being model physics, this is a deduction based on the existence of such a stark disagreement between FV3 and the other modelling, with not many overlapping ensemble members.

Not yet checked the individual EPS mind; some presumption there on my part, I will admit.

Unless one has an in depth knowledge of the model physics I would have thought this a dangerous route to go down. It is not that unusual to get big model differences in the latter half of the run when some minor adjustments with the energy distribution quite early on can make a huge difference later. Just my opinion of course/

Edited July 17, 2019 by knocker

[Singularity]

Fair enough - I’m not expecting serious decisions to be made based on my estimations on this informal forum.

Next time I’ll go with ‘appears as if it might be’.

 

A further note - FV3 also has a big retraction if the subtropical ridge while ECM and UKMO displace it across Europe. Suggests there may be some uncertainty of tropical forcing involved.

Edited July 17, 2019 by Singularity

[knocker]

Although of course it's impossible to deduce worthwhile detail from the EPS mean without the clusters the mean at T192 would appear to mute the heat somewhat

Actually on further reflection this should filed under 'another pointless post '

Edited July 17, 2019 by knocker

[Downpour]

21 minutes ago, knocker said:

Although of course it's impossible to deduce worthwhile detail from the EPS mean without the clusters the mean at T192 would appear to mute the heat somewhat

Actually on further reflection this should filed under 'another pointless post '

If members could talk only about certainties, it would rather defeat the object of this forum. I think speculation about the veracity of ECM’s Day 9 heatwave is valid. It’s been showing on the last two runs now. 

[Summer Sun]

00z ECM has significant rain for some northern and western parts could easily be seeing flooding if it were right by mid next week whilst the South beaks in the heat

[Osca31]

8 minutes ago, Summer Sun said:

00z ECM has significant rain for some northern and western parts could easily be seeing flooding if it were right by mid next week whilst the South beaks in the heat

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