Model Output Discussion 12z 08/07/13

[Downpour]

So is Snokwing's technical summary of where we may be headed a bizarre post? The reason I ask is because I happen to agree with much of what he has said. There's really no point in me sitting down for half an hour and typing out a post which, for the most part, would be a carbon copy in terms of where I think we may be headed. I've consistently plumped for a decent summer (since April infact) and I've consistently plumped for an unsettled spell 2nd half of July and perhaps spilling into early August (before a settling down once more).

The NWP I've seen over the last few days has done nothing to pull me away from this prognosis. Some form of Scandi trough looks likely as we progress towards the day 10 timeframe, which is a response to our resident HP cell pulling away further to the S & W. Just how pronounced/ far west this troughing feature is remains up for debate however. We may end up with a deepish trough which is fairly close to UK shores ala ECM

Or we may end up with a fairly weak affair and a mainly fine picture ala GFS

Whatever happens, surface winds look to switch to a N'ly or NW'ly which will make things feel cooler than they do at the moment- also with more cloud floating about.

No-one is screaming 'washout' as far as I can see.

Some people just have to admit to themselves that it's very rare in the UK to get 6-8 weeks of uninterrupted warm/hot and dry weather in summer or 6-8 weeks of cold and snow in winter.

Looks a fairly dry and warm outlook to me in the reliable timeframe. Long range forecasting is guesswork - so no point looking at August at this stage.

[Captain Shortwave]

ECM ens not looking too bad. Looks like it will turn cooler from Sunday onwards but the weather looks pretty good. Both ECM and GFS ens suggesting the potential for the Azores high to push back north eastwards at day 10.

[nitro_deluxe]

Hard to say, with any high degree of confidence as to what may or may not happen next? As HP battles with low.

How often have been here before

Best just enjoy, keep tempers from fraying and just let things flow...over inflated egos in model-chat aren't always the better solution

Over inflated HP another matter..

[J10]

noaa latest update, azores high to west of uk and influencing our weather to some degree.

 

So in a nutshell, not as good as the past few days but better than a few weeks back, in the short term the High retreats back west and perhaps pushes back in to some extent, but never on top of us as per the current spell.

 

 

Edited July 8, 2013 by Jackone

[damianslaw]

Its a very dry outlook - with many places staying dry right through to early next week, so a notable lengthy dry spell.

 

In terms of temperatures, yes a blip will occur mid week but most places will see above average conditions, low-mid 20's before a rise is expected later in the week especially in the south and east with high 20's back on the cards under increasingly humid conditions.

 

However, there is no signal of heights transferring eastwards which is essential if we are to pull in any real hot air.. instead there is forcing taking place from the NW, this will be very evident on Wednesday as we see a cold front move down the NE flank of the high spilling in cooler cloudier conditions particularly for the NE quarter of the country.

 

Longer term - the most plausible development is for a scandi trough of sorts as heights once again retreat back south and west, how far will determine whether we end up with a chilly showery N/NW flow under a trough influence to our NE, or just a less settled cooler and bit showery airflow from NW/W with the high lurking just to our SW.

 

However we look at things we are in very different territory to where were at this stage in the last 6 summers, but we are a long way from a summer like 95,03 or 06.

[Summer Sun]

GFS 12z ensemble is showing this weekend to be the transitional point from Saturday could well be the hottest day of this spell with somewhere in the south hitting 32c even beyond this weekend the outlook looks a lot drier than previous summers

 

 

The ECM ensemble also shows pressure becoming slightly lower for a time before the Azores has a renewed push towards the end

 

 

All in all a pretty good outlook once this week is out the way many places will be in need of some rain so a few unsettled days wouldn't go a miss compared to previous summers this is a major improvement

[samadamsuk]

not wanting to disagree Damianslaw - feels to me a little similar to 95 so far - I remember the Azores building in and then away in in a cyclic fashion before it settled in later in the summer, with highs building up to 27c or so before it freshened each time. Latest GFS out to t108 and more chance of cyclogenesis near Greenland as the 850 temp gradient and jet profile looks a bit more conducive, so less of a northerly a possibility imo - we shall see hey

[Tony27]

bit late for you to be up gavin, don't normally see you around at this time

 

anyway 18z thus far has the azores high ridging in closer to us for the weekend, stays very warm in england 

Edited July 8, 2013 by Tony27

[Backtrack]

18z is much better than the 12z in terms of longevity of this spell. Has high pressure stronger and closer to our shores than the 12z. Troughing seems to be less of an issue also.

 

All in all, a settled outlook is still on the cards for beyond next weekend, although this settled spell has to end some time, I should think it will not be for another 7-9 days.

[Summer Sun]

Every chance that some where in Yorkshire will hit the first 30c of 2013 tomorrow if GFS is correct with its 29c prediction

 

 

Wednesday and Thursday are cooler days in general in the east with the highest temperatures in the west

 

 

By Friday the heat re-builds with another 30c possible

 

 

But come Saturday the heat just gets wiped out from the north with the best temperatures in the south Sunday looks similar to Saturday temperature wise

 

[Captain Shortwave]

Well that's a surprise, I did think the gfs was rather extreme for Sunday onwards with developments over Scandinavia, but didn't expect the next run to back the other models.Net result is the Azores high is closer to us meaning it will be warmer and more settled into the beginning of next week.

[mushymanrob]

We've been chalking up temps in excess of 26-27c every day since it began - in blazing sunshine. Plenty warm enough down here. Lovely set up.

we have had 2days above 25c, despite the models and tv predictions .we got 21c today in a breezy northeasterly.

[Downpour]

GFS 12z ensemble is showing this weekend to be the transitional point from Saturday could well be the hottest day of this spell with somewhere in the south hitting 32c even beyond this weekend the outlook looks a lot drier than previous summers

The ECM ensemble also shows pressure becoming slightly lower for a time before the Azores has a renewed push towards the end

All in all a pretty good outlook once this week is out the way many places will be in need of some rain so a few unsettled days wouldn't go a miss compared to previous summers this is a major improvement

Indeed. The Azores High is the form horse this summer and has been giving us excellent weather - we don't need day after day of 28c plus. Decent outlook.

we have had 2days above 25c, despite the models and tv predictions .we got 21c today in a breezy northeasterly.

So since the high arrived from the SW four days ago you have had two warm/very warm days? Seems a decent return so far!

[Alex]

Quick observation, some have suggested it tonight but I think the ridge will push back westwards by the end of the weekend but probably not as much as progged by the GFS 12z earlier.

The giveaway is the last 10-14 days of the MJO. It settled in phase 1 for the end of June into July so suggest we take into account composites for both June and July.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

June composites suggest trough to NE and ridge over the UK.

http://www.americanwx.com/raleighwx/MJO/MJO/JunePhase1500mb.gif

July composites suggest trough over the UK.

http://www.americanwx.com/raleighwx/MJO/MJO/JulyPhase1500mb.gif

Suggest June composites are closer to the mark but with a marked Angular momentum drop during this last 10-14 day period, this suggests a less amplified pattern so a westward correction i.e Scandi Trough/Atlantic Ridge.

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gi

Unlikely to have a rinse/repeat of this week for forseeable, not unless we at least start to see a upward trend in GLAAM.

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gif

It's not all bad though, suspect a weakening incoherent MJO may mean we get stuck with a similar pattern to the one progged above, therefore more unsettled in north/east, more settled in south/west?

Add me on twitter: @alexbweather

Edited July 8, 2013 by Alex

[Captain Shortwave]

GFS is fine and warm throughout it's high resolution run. Some southern areas will retain temperatures breaking the 80F mark until next Tuesday and possibly beyond.

F.I develops the Scandi trough in the end, but at 11 days away.

Edited July 8, 2013 by Captain shortwave

[Cheshire Freeze]

Quick observation, some have suggested it tonight but I think the ridge will push back westwards by the end of the weekend but probably not as much as progged by the GFS 12z earlier.

The giveaway is the last 10-14 days of the MJO. It settled in phase 1 for the end of June into July so suggest we take into account composites for both June and July.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

June composites suggest trough to NE and ridge over the UK.

http://www.americanwx.com/raleighwx/MJO/MJO/JunePhase1500mb.gif

July composites suggest trough over the UK.

http://www.americanwx.com/raleighwx/MJO/MJO/JulyPhase1500mb.gif

Suggest June composites are closer to the mark but with a marked Angular momentum drop during this last 10-14 day period, this suggests a less amplified pattern so a westward correction i.e Scandi Trough/Atlantic Ridge.

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gi

Unlikely to have a rinse/repeat of this week for forseeable, not unless we at least start to see a upward trend in GLAAM.

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gif

It's not all bad though, suspect a weakening incoherent MJO may mean we get stuck with a similar pattern to the one progged above, therefore more unsettled in north/east, more settled in south/west?

Add me on twitter: @alexbweather

 

Seems reasonable.

 

GFS 18z produces a carbon copy of the ECM 240 hrs chart, just a few hours later at 288hrs......so well into fantasy land.

 

 

I suspect that the ECM may have the eventual solution but it may turn out to be a tad too quick. We'll have to wait and see how it pans out.

Edited July 8, 2013 by CreweCold

[Tony27]

very warm next week going by the GFS 18z, but there is a 10c difference on this run compared to the GFS 12z, so its all guesswork right now for whether or not the heat will stick around, though the east including me aren't in any heatwave atm, hopefully its our turn next week the west has had it all this summer so far

Edited July 8, 2013 by Tony27

[Duane S.]

What strikes me as fairly unusual is that the S / SW / W has been predominately warmer than the SE / E areas of the UK. Looking at the forecast charts again this morning and that is likely to continue for a while as well with a true Azore High influencing our weather as opposed to the more common of recent times Euro High variant.

 

It looks set fair for at least another week with increasing chances of frontal incursions from the weekend, especially if the AH pulls back West, as looks posssible. Thereafter, anybody's guess!

[Captain Shortwave]

GFS shows absolutely no cool down for Yorkshire southwards this weekend with high twenties predicted quite widely on both days and into next week. Ironically the GFS 00z looks better than the UKMO run this morning. Though even the UKMO has quite a lot of the UK very warm and sunny throughout the weekend.

 

[mushymanrob]

Indeed. The Azores High is the form horse this summer and has been giving us excellent weather - we don't need day after day of 28c plus. Decent outlook.So since the high arrived from the SW four days ago you have had two warm/very warm days? Seems a decent return so far!

 

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.

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

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

 

 

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

[TonyH]

Well it's my friend this week!

[Evening thunder]

I'd suggest a set up like we have now with high sat over us can bring more widespread warmth/sun/high temperatures than a high to the east - for example many northern/western parts joining in this time whereas a high to the east could leave these cooler/cloudier and more prone to Atlantic fronts - even here a high to the east will bring winds of the channel meaning for some parts of the SW especially here near the south coast we have cooler maxima than we are getting at the moment.

 

Highs to the east can bring hotter flows of course, though I don't think we need this for 30c or even 90f, 1976 had hot high centered over us patterns, including the end of June when the June record, 36C was recorded in Southampton (and 33C here at Exeter Airport) this doesn't suggest a south or SE flow.I would like a high to the east for the storm risk and also warm temps, and interesting seeing high temps further east perhaps. So I would like both the current set up and a high to the east in summer.

 

Of course it does depend on location, in a country like the UK with coasts in all directions and different influences depending on where you live, you will never get a set up or wind direction that is the best for everyone.

In this particular instance I can see why some near the east coast may not be so keen on this set up though.

 

Nice to see the models this morning maintaining influence from the Azores high even if it stops becoming a displaced/UK high, so remaining more settled/pleasant the further SW you go.. my area looks like being one of the best areas - maybe the 'English Riviera' and surrounding SW will actually live up to it's name.

Edited July 9, 2013 by Stormmad26

[Captain Shortwave]

Not the warmest run from the ECM but it's fine and settled throughout. After last nights limpet Scandi trough run, it's simply disappeared on this run.

[Frosty.]

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.

Edited July 9, 2013 by Frosty039

[Downpour]

Well it's my friend this week!

Indeed. Given that the AH has been giving us the superb conditions we have had for much of the summer this endless "the Azores High is the enemy" schtick from Mushy is becoming increasingly bizarre. Another good outlook on the reliable timeframe this morning for most of us.