Model output discussion 14/04/18

[SizzlingHeat]

Disappointing UKMO when you compare yesterday's 12z Vs today's.

Seems to have backed the GFS and it's more progressive outlook

On the contrary, the GFS 12z is less progressive again this evening. 

Its still all up in the air at the moment and disappointing there is such discrepancy even for the weekend.

Edited July 17, 2018 by SizzlingHeat

[Frosty.]

@SizzlingHeat

I could understand your concern if you were in scotland but for the south it's still looking great with plenty of sunshine and soaring temperatures!

[Djdazzle]

That’s quite shocking disagreement at 120.

[SizzlingHeat]

1 minute ago, Frosty. said:

@SizzlingHeat

I could understand your concern if you were in scotland but for the south it's still looking great with plenty of sunshine and soaring temperatures!

I'm concerned with the evolution of the UKMO though, rather than pleasant weekend surface conditions. It doesn't seem to be leading down a particularly settled route longer term which the GFS and GEM are keen on. 

[SizzlingHeat]

It's a good job these charts are at 186! Way too far out to be taken seriously but shows the potential route in around a weeks time. Lets hope not!

Southerly tracking jet and large low pressure inbound!

[Singularity]

UKMO's been acting a bit odd today; it's making more of the weakening LP brushing past the UK Fri-Sat than the other models, which on the 12z interferes with the extension east of the Azores High over the following few days. The 00z dropped it further south with the ridge building across to its north, which ironically led to some of the highest UK SLP of the 00z runs for days 5-6.

 

Anyway, watching the GFS 12z roll out, I'm being given an increasingly strong impression that the low south of Greenland next Tuesday is the one that ought to bring about the pattern of a mid-Atlantic trough dug a good way south and a ridge from S UK to Scandinavia or thereabouts. The 12z is making a better effort with that than the 06z did but that low moving NE through the UK is complicating matters.

 

Westward corrections of the mid-Atlantic trough are still needed. It will also help if the trough that stretches SW from near Iceland Sun-Mon can reach more west than south.

Sigh. Sometimes I do wonder why I even bother with GFS!

[mb018538]

Looks like models still struggling for the weekend and beyond - thought by this evening we may have a better handle on things, but it’s looking like we don’t! Warm through Sunday and Monday, then it could be a whole heap of options.

[Singularity]

 

Poor performance the models with respect to handling the MJO; yesterday's runs had little movement or even slight reverse movement (back toward 4) for today, but the actual is continued steady propagation east toward phase 6. Really strange how today's runs haven't adjusted for this at all; still predicting little or reversed propagation.

This (and the associated trade wind patterns; stronger in the Central Pacific) seems likely to be the main reason why the modelling for next week just feels strange at the moment; they're not moving the MJO in a fashion that ties in with the overall emerging El Nino trends, so there's a conflict of forcing being fed through (phases 5 and 6 promote lower heights to our E and NE, contradicting with what rising AAM promotes).

So if the MJO continues to propagate steadily east rather than slow to a crawl in phase 6 or decline gradually in phase 5, we should soon see an improvement in UK-Scandinavian ridging being projected for mid-late next week. 

Still possible that the MJO won't behave so helpfully, though - it depends to what extent this behaviour from the models is driven by a genuine counteracting development or confusion as a result of other tropical phenomena.

M. Ventrice's alternate analyses of the MJO suggest it's the confusion - but I'm not sure if the models read-in MJO data in the format used above having processed the raw data through the RMM formulas, or work  without applying such processing. If it's the latter then it shouldn't matter that the RMM approach is making such a mess of the MJO analysis.

 

 

The plot thickens!

I must admit that even knowing the limitations of NWP modelling, I've been disappointed by the way they've behaved over the past few days - I'd hoped to see a clearer trend toward more UK-Scandinavia ridging emerge by now. 

At least the in-house models used by the Met Office seem to be handling things more like I was hoping for, judging by their written updates for days 6-15 and 16-30.

[Fourty Point Three Degrees]

GFS 12 is utterly vile please bin it!!!  I know D8 its long way off but cant help thinking we're back to the flabby Atlantic and low pressure from next week just as schools break up and theres a hosepipe ban on the horizon.    I await the ECM...

Edited July 17, 2018 by 38.5*C

[Mike Poole]

Disappointing 12 set so far as others have said, GFS goes right down hill, GEM not much better, UKMO ok-ish but doesn't go as far as the timescale of interest - which it should be noted is beyond the reliable.  Pick so far is the ICON:

But GEFS mean at T300 suggesting that eventually maybe the coffee is being smelled, if not drunk.

Edited July 17, 2018 by Mike Poole

[Badgers01]

It’s been a common theme for the models to dangle very high uppers and back away - some posters were saying 35c this weekend but it’s looking unlikely,  29/30c for south is great but it’s the same every weekend ! 

[Weather-history]

Last Tuesday's GFS 12z run for today

 

And what actually happened

GFS 12z last Tuesday  suggested a far more unsettled spell for now than is actually going to happen

Edited July 17, 2018 by Weather-history

[shaky]

Much better ecm and continues on from the 00z run!!ukmo has gone crazy today swinging from.one end of the spectrum to the other and gfs has gone trough crazy in fi!!

[Guest]

2 minutes ago, shaky said:

Much better ecm and continues on from the 00z run!!ukmo has gone crazy today swinging from.one end of the spectrum to the other and gfs has gone trough crazy in fi!!

GFS FI can be completely binned of course, whether it showed a tropical paradise or early autumn - it's been all over the place recently 

ECM looking steady and pretty hot for the weekend. UKMO an interesting one purely because of it's difference to the 00z.

[Mike Poole]

ECM looks quite similar to the ICON earlier, here T168:

Great run this, few frames to go!

Edit T192:

Roll on summer! 

Edited July 17, 2018 by Mike Poole

[bradymk]

Will the trough to our west be sharper and dig further south closer to reliable?? 

Here it is at 168 and 192. Wouldn’t take much....

[Tamara]

Further proof that it doesn't matter how many times one writes signals lead models and not the other way around.

Its very odd how in the space of a couple of hours or so having left to enjoy some lovely summer afternoon sunshine how NWP appears to have (allegedly) conspired to re-write the outlook

Genuinely, how does one or two operational outputs promote such knee jerk response both on this and perhaps even more so on the model moods threads? Now, or at anytime.

 I broke a usual habit and looked at them for myself and then, mea culpa, admit breaking another habit that involves not looking at the GEFS ensembles more than once every other day to gauge the non NWP continuity ( that also allows me the added benefit of being blissfully ignorant of the NWP upgrade/downgrade roundabout)

Notwithstanding the GSDM perspective, and having been satisfied quite sufficiently by the evolution of the GEFS 12z ensembles this has left me more bemused than ever what has promoted the hiatus?.

Maybe someone can tell me because I honestly can't see it

Have a nice evening - the exact details are irrelevant of course but if one really needs an operational antidote take the 12z ECM.....

..and breathe... :

 

[Methuselah]

11 minutes ago, Tamara said:

Further proof that it doesn't matter how many times one writes signals lead models and not the other way around.

Its very odd how in the space of a couple of hours or so having left to enjoy some lovely summer afternoon sunshine how NWP appears to have (allegedly) conspired to re-write the outlook

Genuinely, how does one or two operational outputs promote such knee jerk response both on this and perhaps even more so on the model moods threads? Now, or at anytime.

 I broke a usual habit and looked at them for myself and then, mea culpa, admit breaking another habit that involves not looking at the GEFS ensembles more than once every other day to gauge the non NWP continuity ( that also allows me the added benefit of being blissfully ignorant of the NWP upgrade/downgrade roundabout)

Notwithstanding the GSDM perspective, and having been satisfied quite sufficiently by the evolution of the GEFS 12z ensembles this has left me more bemused than ever what has promoted the hiatus?.

Maybe someone can tell me because I honestly can't see it

Have a nice evening - the exact details are irrelevant of course but if one really needs an operational antidote take the 12z ECM.....

..and breathe... :

 

I really don't see how anyone can argue with that, Tamara...anyone who thinks that the models lead the weather is, IMO, sadly deluded...Even the Russian HAARP machines - contrary to what some conspiracists might say - haven't mastered that one yet! 

Anywho - it'll be Christmas soon!

[Mike Poole]

14 minutes ago, Tamara said:

Further proof that it doesn't matter how many times one writes signals lead models and not the other way around.

Its very odd how in the space of a couple of hours or so having left to enjoy some lovely summer afternoon sunshine how NWP appears to have (allegedly) conspired to re-write the outlook

Genuinely, how does one or two operational outputs promote such knee jerk response both on this and perhaps even more so on the model moods threads? Now, or at anytime.

 I broke a usual habit and looked at them for myself and then, mea culpa, admit breaking another habit that involves not looking at the GEFS ensembles more than once every other day to gauge the non NWP continuity ( that also allows me the added benefit of being blissfully ignorant of the NWP upgrade/downgrade roundabout)

Notwithstanding the GSDM perspective, and having been satisfied quite sufficiently by the evolution of the GEFS 12z ensembles this has left me more bemused than ever what has promoted the hiatus?.

Maybe someone can tell me because I honestly can't see it

Have a nice evening - the exact details are irrelevant of course but if one really needs an operational antidote take the 12z ECM.....

..and breathe... :

 

Yes, you are absolutely right, but partly wrong as well.  I think most of us are expecting that something like the ECM 12z is where we're headed, yes, but I've said before model watching is similar to gambling, I relate to it, people need the highs and lows, and when there is exceptional weather on offer, the twists and turns are part and parcel of this rather obscure hobby.  So I won't breathe, not just yet!  Even though I reckon you've got the expected evolution right! 

[Singularity]

A better effort from the 12z ECM:

  

Having spotted Tamara's post from earlier (and oh look, there's another one!) I sense that I may have been worrying too much about interference from the MJO driving the counter-intuitive model behaviour for mid-late next week; with a seasonal wavelength change that supports moving a trough in and counteractive forcing that the models struggle to read reliably, it's really no surprise that some progressive runs are turning up from time to time. Strange thing is, I had that view a few days ago but then lost sight of it. An intense working life can have that effect sometimes .

Even so, I continue to look at each set of deterministic runs out of curiosity as to how soon they can resolve the problem at hand. That's why I look at GFS, as daft as that model can seem sometimes! 

[Mike Poole]

ECM mean as far as I can see sticking to the script.  T240:

heights into Scandi, Azores retreating to maybe allow plume scenarios to develop.  Was where we were wasn't it.

[Man With Beard]

Surprised to see ECM reintroducing rain for the weekend - it had ditched it on virtually every ensemble the past two days 

[Singularity]

25 minutes ago, Man With Beard said:

Surprised to see ECM reintroducing rain for the weekend - it had ditched it on virtually every ensemble the past two days 

Follows UKMO making more of that low too. Still a weakening feature as it heads south but sufficient to make Saturday another ‘small chance of catching a shower’ day for S and SE England. There’s been a number of those down here in the last week or so (but only a few spots of rain so far).

Sunday has for some time looked to be ‘clean up day’ for England in particular with sunnier skies and temps getting back closer to 30 in places having ‘only’ been mid-high 20s during the preceding few days.

 

Nice to have some more summery weather to look forward to even as we wait for mid-late next week to be resolved.

[tight isobar]

All very well...

'However'.. as a reiteration..

The ens start to fall into the pack...

As the ops-etc- start to evaluate.

Members and mean take the contrast and take note of ridging-as once again angular-synopsis chase the tail.

Wide open flow at maritime/pacific..

Allow yet again' the narrow margin on large scale....triangular direct heat evolution...

With the now out suite models decipher.

The raws shall follow there ensembles-and with the angular flow should see-agree...

Its a ridge builder with amp to shut down any complexities of pm airflow/or-no tropical maritime influx.

AZHP-has circular-and sea temps-tresolve... 

August lining as the notable summer month!!!

 

For guidance;..

The ridge miss-placement with overall, miss manage-@short range outs....

Clockwork dymamics...that look likey to fall into favour for the nw euro sector..with non rolling Atlantic micro system's..as the roll will temper-inflow!!

Edited July 17, 2018 by tight isobar

[Cheshire Freeze]

A warm, wet run from the GFS 18z, some much needed rain from day 7

Edited July 17, 2018 by CreweCold