Model Output Discussion 12z 08/07/13

[ANYWEATHER]

Just look at the difference between last nights 12z ecm and this mornings run at T+240! Gfs is similar to last nights ecm out at that range. Just shows the pitfalls at looking out that far out, but always good for a bit of a laugh though!

[johnholmes]

2/5 days with temps over 25c, when at least 4 of then supposed to be?

 

lets get this straight...im more then happy with the weather we have got, its still the best spell most of us have had for 7 years. my gripe though is how WRONG the temp predictions have been. 21c yesterday when even on the tv that morning we were promised 27c?...  plus those temp prediction charts posted here also wrong by 6c .... so yes its a very nice spell, but not what was promised.

 

this mornings models seem to be struggling to handle events after saturday, but it appears that the high will drift back to the azores, which will return us to those cool northwesterlies. this mornings anomaly charts support this in the medium range. so the azores high once again becomes our enemy.

 

 

 

as for the mjo... i cant take it seriously as i cant see any agreement between the various predicted tracks, nor any correlation between the phases and the composite charts to what we actually get.

JulyPhase3500mb.gif

this phase (3) is the closest to what our current synoptics look like... but..

ALL_emean_phase_full.gif

which predicted model do you chose to believe? only the ecm suggests a breif phase 3.

 

Recm1922.gif

 

the retreating high displaying why the azores high isnt our freind.

I am unsure as to why you make such posts mushy

re the predicted max temperatures, for eastern England the models, last week, did not show N Sea low St for Monday, most outputs suggested it for Wednesday. Thus the max prediction even yesterday was wrong as they did not evne then get the St clearance time correct. No need to make so much about it-it happens, look for the reason rather than carping on about it, lesson learnt perhaps for next time for us?

re the MJO, not sure how 'up' you are on this topic as I find it very hard to really grasp. However most folk accept that when it is in low orbit, actual or predicted the 500mb charts can often be quite different. Best to remember that I suspect?

It really would do your status on here a power of good if you showed a bit more objectivity mate, I know you are not the only one but it needs saying.

looking at the ouput last evening from NOAA on the 500mb charts and it has started to show, especially on the 8-14 another build of heights over the Atlantic extending towards the UK, not too different from how it showed this current spell 10-12 days ago. This idea has been picked up on the ECMWF output this morning although not on the GFS. So, 'maybe' another build of pressure in about 10 days time. Certainly no sign of a repeat at the moment of wash out summer weather like last year.

Edited July 9, 2013 by johnholmes

[Frosty.]

Pretty fair 00z output overall this morning, at least for the south with high pressure or at least a strong ridge holding across the south with fine and warm weather in control, the gem 00z has an unsettled and cooler blip next week but then shows a recovery as high pressure builds in again, the navgem and gfs are looking good for the south but the north of the uk will probably be turning more unsettled at times but for the south there is little or nothing to moan about really, plenty for folk in scotland to moan about though as time goes on.

[Frosty.]

Tomorrow is looking pretty groovy across the uk.

[Skeggy Winter Storm]

Pretty fair 00z output overall this morning, at least for the south with high pressure or at least a strong ridge holding across the south with fine and warm weather in control, the gem 00z has an unsettled and cooler blip next week but then shows a recovery as high pressure builds in again, the navgem and gfs are looking good for the south but the north of the uk will probably be turning more unsettled at times but for the south there is little or nothing to moan about really, plenty for folk in scotland to moan about though as time goes on.

mornin Frosty just quick question on the last map where it shows numbers over sea are they the actual sea temps or air temps

[chionomaniac]

I am unsure as to why you make such posts mushyre the predicted max temperatures, for eastern England the models, last week, did not show N Sea low St for Monday, most outputs suggested it for Wednesday. Thus the max prediction even yesterday was wrong as they did not evne then get the St clearance time correct. No need to make so much about it-it happens, look for the reason rather than carping on about it, lesson learnt perhaps for next time for us?re the MJO, not sure how 'up' you are on this topic as I find it very hard to really grasp. However most folk accept that when it is in low orbit, actual or predicted the 500mb charts can often be quite different. Best to remember that I suspect?It really would do your status on here a power of good if you showed a bit more objectivity mate, I know you are not the only one but it needs saying.looking at the ouput last evening from NOAA on the 500mb charts and it has started to show, especially on the 8-14 another build of heights over the Atlantic extending towards the UK, not too different from how it showed this current spell 10-12 days ago. This idea has been picked up on the ECMWF output this morning although not on the GFS. So, 'maybe' another build of pressure in about 10 days time. Certainly no sign of a repeat at the moment of wash out summer weather like last year.

 

 

Would agree on this point. With the MJO decreasing in amplitude - it will be less of a player. You are right to urge caution, John, with those looking into too much from the MJO composites - those should remember that the MJO is just one component of the Global Wind Oscillation that measures transfer energy momentum from the tropical regions to the mid latitudes and also from the earth to the atmosphere up to the stratosphere. Without taking all of this into account one could get led up the garden path by looking at the MJO in isolation.

 

FWIW I see a re-ocurring displaced Azores high being the main theme throughout July without a major increase in any MJO wave amplitude.

[UV-RAY]

A generally good Ecm 00z operational run, at least for the south of the uk, high pressure throughout and only very brief interruptions to the sunny and warm / very warm conditions, for scotland & n.ireland, more changeable with some unsettled weather but fine and pleasantly warm at times.

Indeed Frosty, I can't see why one or two are despondent really. Too me it looks a fantastic outlook for the next 10+ days, granted it may well be less warm but come on compared to the last 6 summers its a belter, besides that its the UK not the Bahamas.

[Cecil Hogmanay Melchett]

Yes i think those trumpetting a pattern change  are going to be backtracking very soon.

[Summer Sun]

00z ensembles show the possibility of another rise in the uppers at the end of the run this morning

 

 

Even when they do fall next week they never get lower than average so we can't complain really this is one of the best July months for a number of years

[Summer Sun]

Look at the models we could see some thunderstorms breaking out in parts of the south on Saturday

 

[Frosty.]

mornin Frosty just quick question on the last map where it shows numbers over sea are they the actual sea temps or air temps

2m air temps, sea surface temps nearer 10 to 12 celsius I would think.

[shedhead]

The overnight GFS appears to have backed away from it's previous weekend evolution and is now showing maxima of 15-20c on Sunday across Scotland, rather than the 11-15c it was touting yesterday. That said I would still expect a steady cooling off next week as the air becomes increasingly Atlantic influenced, indeed if you look at this mornings ECM that trend is rather more pronounced, ditto UKMO. So nothing has really changed overall from yesterday, what we have seen across the last 24hrs is nothing more than typical inter model variability in the T+120-144hr range, so for me the only real questions remain how pronounced and how long will the breakdown be.

Edited July 9, 2013 by shedhead

[Scorcher]

2m air temps, sea surface temps nearer 10 to 12 celsius I would think.

 

Actually Frosty they've risen recently, I think the North Sea temps are mostly 14-15C off the coast of Eastern England so those air temperatures are pretty close to the sea surface temperature. 

[Scorcher]

The overnight GFS appears to have backed away from it's previous weekend evolution and is now showing maxima of 15-20c on Sunday across Scotland, rather than the 11-15c it was touting yesterday. That said I would still expect a steady cooling off next week as the air becomes increasingly Atlantic influenced, indeed if you look at this mornings ECM that trend is rather more pronounced, ditto UKMO. So nothing has really changed overall from yesterday, what we have seen across the last 24hrs is nothing more than typical inter model variability at the range in question, so for me the only real questions remain how pronounced and how long will the breakdown be.

 

But there is a change in the sense that the weekend is looking very warm/hot for most of England now whereas before the GFS wanted to bring the cooler air in earlier. It means many could still have a hot weekend when it looked last night like that might be restricted to the south of England. Big change as far as I'm concerned.

 

Also for me there are big changes from last night further ahead with that trough over Scandinavia not really influencing us at all- I can't really see a breakdown at all this morning from the GFS. Slightly cooler uppers moving in for early next week but many places will have average to slightly above average temperatures with nothing particularly cool on the cards.

[Captain Shortwave]

Well yesterday there was good support for conditions to turn cooler nationwide on Sunday, now that's been moved back to Tuesday and any cooling down further north after the cold front moves through is less severe. All in all good progress this morning.

[Downpour]

Yes i think those trumpetting a pattern change  are going to be backtracking very soon.

There was certainly some premature self back-slapping going on last night. We shall see, but the Azores High is the form horse this summer. 

[shedhead]

But there is a change in the sense that the weekend is looking very warm/hot for most of England now whereas before the GFS wanted to bring the cooler air in earlier. It means many could still have a hot weekend when it looked last night like that might be restricted to the south of England. Big change as far as I'm concerned.

 

Also for me there are big changes from last night further ahead with that trough over Scandinavia not really influencing us at all- I can't really see a breakdown at all this morning from the GFS. Slightly cooler uppers moving in for early next week but many places will have average to slightly above average temperatures with nothing particularly cool on the cards.

That was exactly my point, I only referred to Scotland as that is where temps were shown to be significantly lower on Sunday this time yesterday. Agree that GFS has also unwound any breakdown to a degree next week, but at the same time UKMO and ECM have ramped it up a bit, but as I keep saying things have to be kept in context here.  No one as far as I'm aware is talking about a breakdown in the sense of a return to nationwide cool, wet and windy weather; any breakdown has and still looks to be most noteable from a temperature perspective, with the vast majority of the UK remaining significantly drier than average.

Edited July 9, 2013 by shedhead

[Downpour]

The overnight GFS appears to have backed away from it's previous weekend evolution and is now showing maxima of 15-20c on Sunday across Scotland, rather than the 11-15c it was touting yesterday. That said I would still expect a steady cooling off next week as the air becomes increasingly Atlantic influenced, indeed if you look at this mornings ECM that trend is rather more pronounced, ditto UKMO. So nothing has really changed overall from yesterday, what we have seen across the last 24hrs is nothing more than typical inter model variability in the T+120-144hr range, so for me the only real questions remain how pronounced and how long will the breakdown be.

What "breakdown" would this be then? And to what? Very good outlook for most of us in the reliable timeframe. 

[Frosty.]

Actually Frosty they've risen recently, I think the North Sea temps are mostly 14-15C off the coast of Eastern England so those air temperatures are pretty close to the sea surface temperature. 

That's good to know scorcher, since sea surface temperatures, especially the north sea, were significantly below average not so long ago, at least that's one less reason not to have more hot spells this summer.

Edited July 9, 2013 by Frosty039

[lorenzo]

What a cracking spell of weather, dare I say it - too hot for some !! Am not complaining. We have waited for what seems like ages for a UK High to be parked over us and it's great, obviously buoyant as am off work today - frazzling.

 

Interesting charts about too. For posterity love the Old school wetterzentrale view of current preceedings, crimson galore.

 

In relation to the MJO, the 8th July update shows some less coherent influence with the feature dissipating over the maritimes, how much Typhoon Soulik, predicted to bomb in next 24hrs demises / changes things who knows. MJO phases looking more interesting for Hurricaine season to start moving along..

 

One thing for sure the July phase 1 analog is ugly, GFS wandering there eventually.

 

UKMA - the control run has an analog much easier on the eye ( these out to 22nd).

 

GWO still in low circuit which can only be a good thing and this supports the idea of the Azores ridge meandering west a bit to then re-establish itself, some June / July / August analogs from Nick Schiraldi page, At Last Analog sets for GWO. One of the holy grails of long range forecasting cracked?

 

Finally, GEFS reforecast product V2, like this one as it strips out the anomalies, that trough can stay up North of us as long as it likes please..

 

Am hopeful that we can eek out some more ridge action, wouldn't it be great if just finally this pattern echoed into high and later summer, we seem to get stuck in a rut with everything else on occasion. Why not the good stuff for once !! 

 

 

 

 

 

[Frosty.]

Although the Ecm 00z ensemble mean shows a very slow decline in the overall pattern, the south remains generally warm or very warm until at least the middle of next week, only the north of the uk gradually becomes cooler and fresher with a slow increase in unsettled weather as time goes on, for most of the uk it still looks very reasonable, especially when measured against the dross we had for most of last summer, and the azores anticyclone is well placed to make a comeback once the more unsettled weather has pushed away to the northeast later next week but southern england in particular is set to have a lot more sunny and very warm weather during the course of the next 7-8 days, tomorrow we have a tiny blip in the gorgeous weather with more cloud and less warm weather spreading southwestwards across the uk but southwest england still looks very warm and sunny tomorrow with temperatures of 25-27 celsius, around 80f, temps elsewhere tomorrow closer to the low 20's celsius but then warming up again.

Edited July 9, 2013 by Frosty039

[shedhead]

06 GFS very much more in line with the overnight ECM and UKMO with regards to Sun/Mon, meaning confidence in the overall evolution continues to firm up. So things still look set to become noticeable cooler and fresher for Scotland, NI and N Eng early next week, while the south also becomes cooler and fresher, but not to such a large extent. Despite the change however rainfall is still expected to be patchy, even negligible for many away from the far NW, but the main question imo remains where do we go after midweek?

Edited July 9, 2013 by shedhead

[Buzzit]

Interesting pattern of output from the GFS operational in last 24hrs.

8/7 6z showed 5' 850s for London on 14/7

8/7 12z showed 8' 850s for London on 14/7

8/7 18z showed 8' 850s for London on 14/7

9/7 0z showed 12' 850s for London on 14/7

The rise in 850s was also reflected in the range of the ensemble output which narrowed spread and lifted temperature over the 24 hours.

9/7 6z showed 8' 850s for London on 14/7

It will be interesting to see whether today follows the same pattern as yesterday with respect to the expected 850s, through the last 24 hours we have seen an overall increase in expected 850 temps for London and parts SW for Sunday. Am also wondering whether initialisation conditions as the day warms up is having an effect - though unlikely I guess.

 

The other thing that is baffling me with output at the moment is how quickly the GFS takes a Greenland area with low pressure everywhere and replaces it with 1024+ high pressure within two days ? Witness the 6z it has 1008mb slack pressure over Greenland on the 17th July and then within 24 hours it has a big fat high with solid 1024mb high pressure = bonkers

Edited July 9, 2013 by Buzzit

[Suburban Streamer]

Great link Lorenzo thanks for posting

[Weather Boy]

Interesting pattern of output from the GFS operational in last 24hrs.

8/7 6z showed 5' 850s for London on 14/7

8/7 12z showed 8' 850s for London on 14/7

8/7 18z showed 8' 850s for London on 14/7

9/7 0z showed 12' 850s for London on 14/7

The rise in 850s was also reflected in the range of the ensemble output which narrowed spread and lifted temperature over the 24 hours.

9/7 6z showed 8' 850s for London on 14/7

It will be interesting to see whether today follows the same pattern as yesterday with respect to the expected 850s, through the last 24 hours we have seen an overall increase in expected 850 temps for London and parts SW for Sunday. Am also wondering whether initialisation conditions as the day warms up is having an effect - though unlikely I guess.

 

The other thing that is baffling me with output at the moment is how quickly the GFS takes a Greenland area with low pressure everywhere and replaces it with 1024+ high pressure within two days ? Witness the 6z it has 1008mb slack pressure over Greenland on the 17th July and then within 24 hours it has a big fat high with solid 1024mb high pressure = bonkers

 

Have a question; half rhetorical, half not, but why is it bonkers?

 

I'm not saying that it's likely to verify or anything, but synoptics can change dramatically in 48 hours, so why not that?  Do you mean lack of background signals in support?

Edited July 9, 2013 by Weather Boy