Model Output Discussion 18z 28/07/13

[Frosty.]

Let's start with some good news, the GEFS 00Z mean looks generally settled from start to finish, especially for england & wales where the azores/atlantic ridging looks strongest, due to the ebb and flow of the azores ridge, scotland, and in particular the further north you go, has a risk of some less settled interludes but in general the weather is becoming set fair, however, we still need to keep an eye on a trough digging southeast from iceland by the end of the week ahead, it will probably be a near miss or just graze across the far northeast of the uk mainland and before that, later tomorrow, a band of thicker cloud with patchy outbreaks of rain edging southeast through scotland and into n.ireland but as these weakening fronts bump into the higher pressure further south, the ppn should die out and even the band of cloud will break up, so for the southern half of the uk, the front should have little or no effect as the azores ridging pushes in even more strongly from midweek. It looks like warm and sunny weather will dominate the week ahead, especially the further south you are but tomorrow am there could be some mist around which will need a few hours to burn off..it's a very good looking outlook, the PFJ remains well to the north of the uk for most of the time, along with it's autumnal weather, the uk stays in summery weather.

 

The Ecm 00z op turns into another horror show...after a week of fine and warm weather.... but again I think it will be very wrong, but its something to think about.

Edited August 25, 2013 by Frosty039

[Yarmy]

ECM takes the low straight through Scotland next weekend:

 

http://www.meteociel.fr/modeles/ecmwf/runs/2013082500/ECM1-144.GIF?25-12

 

UKMO/GFS keep it further N through Iceland:

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013082500/gfs-0-144.png?0

 

http://www.meteociel.fr/ukmo/runs/2013082500/UW144-21.GIF?25-07

 

 

Either way, pressure starts to build again over the UK after the low moves through and decays.

[Jezzer]

Morning all, I see that Matt Hugo is getting very excited on twitter about prospects of  a "possible cool/unsettled NW'ly next wkend" 

 

He appears to be siding with everything but the GFS which still looks good for the south of the UK

Edited August 25, 2013 by Jezzer

[mushymanrob]

If we were to believe the means all the time then the last 2 weeks at least should have seen us in heatwave conditions with no rain. But yet we have barely above ave temps and torrential rain in some parts today. Seeing is believing. And all this memorable summer malarky, really ?, yeah its been nice for the most part but memorable hmmm

 

agreed.... 3 weeks of good weather in july does not a memorable summer make... unless we remember it for not being as dire as the last 6 ! outside those 3 weeks its been pretty average at best.

 

i see this chart

 

 

has caused abit of a stir... coldies starting to get their hopes up whilst those of us still in summer mode suggest theres no support for it (in denial?)

as i see it, its perfectly feasible and doesnt really fly against what the upper air pattern the anomaly charts suggest. those charts still keep the azores ridge firmly to our southwest

 

... and thats where its expected to stay

 

 

so this morning theres no support for the azh to displace and track to our east (resulting in warm/hot weather). as per the gfs in fi

 

 

and this synoptic chart is typical of what we can expect over the next week-ten days, possibly further.

 

 

so warm in any sun, cloud will be an issue especially in the northwest, best sunshine/warmth in the southeast, mainly dry, but with the chance of a cooler northwesterly if the high retreats abit and allows a coldfront to sink across the country....before the high ridges back.

Edited August 25, 2013 by mushymanrob

[bluearmy]

there is more than the sniff of a trend towards ecm's 12z solution of yesterday. however, what we should now be looking for is if the ens on ecm trend the same way. the gefs have drifted a little in that direction although they are flatter with the spread pattern and as mentioned above, the southern half of the uk stays reasonable in general throughout. as tamara has said, the ecm op remains prone to over amplification post day 6.  is this the time it will verify ?  at the moment, i'd say somewhere between with a depression tracking iceland/shetland/denmark looking favoured. the ecm 00z op approx 150 miles too far south for me.

[draztik]

The GEM seems to endorse what the ECM started to show last night, only is a lot more unsettled as its run continues. as has been suggested, when you have an ensemble mean with the core of the HP out to our west, these incursions were always possible. The models once again paint a very different picture than that of 2 runs ago, with a more Autumnal feel to things. You couldn't make it up!

GEM at @150 216 & 240

Edited August 25, 2013 by draztik

[tinybill]

http://www.meteociel.fr/modeles/gefs_cartes.php?code=16&ech=192&carte=&mode=0

 

morning  after yesterday  monsoon weather here in the  east its dry!!  , and looking deep in to  fantasy  world its looking  like BBQ season is over  cooler  weather is heading our way

Edited August 25, 2013 by tinybill

[Frosty.]

The fax charts look nice and settled through the second half of next week, only the far northwest corner of the uk having weak fronts brushing around the top of the strong azores/atlantic ridge..set fair and warm for most of the uk is how I see it.

[Polar Maritime]

I see the ECMWF  is still sticking to it's gun's for a cooler Northerly flow during the turn of the season. As pointed out a few days ago.

 

 

 

 

Although the GFS has the Low further North, it would feel much cooler. We shall see..

 

Edited August 25, 2013 by Polar Maritime

[Frosty.]

I see the ECMWF  is still sticking to it's gun's for a cooler Northerly flow during the turn of the season. As pointed out a few days ago.

 

 

Although the GFS has the Low further North still, We shall see..

 

come on gfs..I have faith in you

[shedhead]

If we were to believe the means all the time then the last 2 weeks at least should have seen us in heatwave conditions with no rain. But yet we have barely above ave temps and torrential rain in some parts today. Seeing is believing. And all this memorable summer malarky, really ?, yeah its been nice for the most part but memorable hmmm

Absolutely right, had the models verified as shown at times a week of so ago we'd be in the middle of a protrated hot spell now, but not all of us bought into it of course. Summer 2013 has been considerably better than many recent ones, but only memorable for what I'd describe as the number of 'usable days' i.e those that have not been overly cool, overly wet or overly hot.  Looking forward, the model suite suggests the final week of the summer offers more of the same, with a good deal of usable weather for most, but still no sign whatsoever of the much vaunted hot spell/heatwave..call it what you will.

[draztik]

Absolutely right, had the models verified as shown at times a week of so ago we'd be in the middle of a protrated hot spell now.

the ensembles didn't indicate heatwave conditions tho, it was the ops that certain members jumped all over to proclaim a hot spell.

[Frosty.]

Although the Ecm 00z looks absolutely rancid next weekend, a few days later it comes bouncing back with this peach of a chart, only the Gem 00z descends into a tailspin of unsettled and cooler weather that it never recovers from, the gfs, ukmo & navgem show a glancing blow from that trough which only briefly affects scotland before pressure rises again. 

[Milhouse]

Well, its looking dry and settled today and much of the upcoming week. Not bad to get 2/3 decent days in a bank holiday weekend. Friday looks like it may mark the beginning of a cooler spell of northwesterlies but the mean outputs this morning show it as a temporary blip before warmth comes back in off the Atlantic.

[snowking]

Shorter term it certainly looks like becoming settled and pleasant for much of the UK once again to end the month.

 

Longer term, in terms of the debate on the reliability of the EC32, thats one that could go on for weeks and weeks. What I must say is that I can't disagree too much with its suggestions beyond the opening days of September.

 

Pretty solid agreement on a phase 1 MJO setup:

 

 

These signals can always be slightly lagged, and indeed I suspect thats what we will see here. But when we look at what phase 1 brings us in to September:

 

SeptemberPhase1500mb.gif

 

So, are there any signs of such a signal yet from the 'standard' NWP as it were?

 

Well, as of yet actually no. I suspect this is a signal that will gather pace in the coming week. We can see some very small signs of a trough digging in to Europe on the NAEFS anomalies this morning:

 

 

But ultimately its a very weak signal and the trough shown there is far enough East to leave the UK under the influence of the azores ridge instead. Of course we may well end up with such a scenario - those MJO composites are far from full proof, but beyond the 5-7th September as a rough guide, I would be looking for a troughing signal to gain momentum at the moment.

 

SK

I havn't got much time this morning but needless to say these thoughts still stand this morning, with gathering momentum for some form of troughing close to the North of the UK - though much sooner than I had expected I must say.

 

I suspect, as has been alluded too already by Tamara and others, that the amplification in the pattern depicted by the ECMWF may still tone down somewhat for this period, and adjust to something closer to the GFS solution. However, what is clear is that medium-range NWP is now picking up on the MJO phase 1 signal, and will likely drive with that pattern as a basis through the FI period in the coming 10-14 days.

 

SK

[Scorcher]

Morning all, I see that Matt Hugo is getting very excited on twitter about prospects of  a "possible cool/unsettled NW'ly next wkend" 

 

He appears to be siding with everything but the GFS which still looks good for the south of the UK ukmaxtemp.jpg

 

Why would anyone get excited about that at this time of year, it would only bring temperatures in the mid teens. And people say Matt Hugo doesn't have a cold bias! I see the thread is coldie-dominated this morning for the most part- surprised really as it looks dry and warm for most over the next few days. Don't be misled and enjoy the warm weather that's coming is what I say.

[Frosty.]

Why would anyone get excited about that at this time of year, it would only bring temperatures in the mid teens. And people say Matt Hugo doesn't have a cold bias! I see the thread is coldie-dominated this morning for the most part- surprised really as it looks dry and warm for most over the next few days. Don't be misled and enjoy the warm weather that's coming is what I say.

Exactly, only the Gem 00z goes pear shaped, the ecm has a rapid recovery and let's not forget the most important thing here, the week ahead looks warm and sunny with light winds, if next weekend is unsettled, it should only be a blip in an otherwise summery pattern.

Edited August 25, 2013 by Frosty039

[Jezzer]

Why would anyone get excited about that at this time of year, it would only bring temperatures in the mid teens. And people say Matt Hugo doesn't have a cold bias! I see the thread is coldie-dominated this morning for the most part- surprised really as it looks dry and warm for most over the next few days. Don't be misled and enjoy the warm weather that's coming is what I say.

Yep, always baffles me. I can understand that some people may find temps in excess of 30oc too much for a number of reasons, notably health. But seeking the sort of dross that the South East experienced yesterday in the summer months does seem odd.

 

Anyway, I'm just glad that I've got three days off starting tomorrow and the forecast is looking good for the south. As far as next weekend is concerned it looks like it's still all to play for.

Edited August 25, 2013 by Jezzer

[draztik]

 

the ECM ensembles for Glasgow, shows a declining theme in terms of temp, most pronounced around the weekend of the 31st. Conditions improve thereafter, with a return to above average temperatures, and falling precipitation.

 

(thanks Summer Sun for the graphics)

[Mr Frost]

Why would anyone get excited about that at this time of year, it would only bring temperatures in the mid teens. And people say Matt Hugo doesn't have a cold bias! I see the thread is coldie-dominated this morning for the most part- surprised really as it looks dry and warm for most over the next few days. Don't be misled and enjoy the warm weather that's coming is what I say.

Yes, how dare anyone post/talk about anything other than heatwaves or high pressure dominated charts.People can discuss anything the charts show, it is the model output discussion after all. I prefer Winter but I love Summer also. How about a bit of realism on outlooks and respect for everyone who makes a contribution to this thread? You can't label someone a coldie just because they have posted a chart that is not banging on about fantastic Summer weather. Great posts from John Holmes and Bluearmy last night that showed facts on model verification and the definition of a meaning. Edited August 25, 2013 by Mr Frost

[Summer Sun]

Here is Gibby's unbiased view on things this morning with his high detailed analysis

 

Good morning everyone. Here is the detailed weekly report on the model outputs of GFS, UKMO, The Fax Charts, GEM, NAVGEM and ECM for today Sunday 25th August 2013.All models show an area of flat synoptic conditions across the UK as Low pressure exits the far SE. With a Northerly tendency for the wind it will be largely dry and bright across the UK apart from a few scattered showers this afternoon. It will feel quite warm in places. Bank Holiday Monday will see a ridge across the UK with fine and dry weather for many with sunny spells. An old upper trough in the SW could give rise to an isolated shower here otherwise a dry bank Holiday Monday is likely for all. Tuesday shows a weak front crossing South over the UK with a band of thick cloud and light rain moving SE too across all areas clearing again in the NW later. This clearance travels SE to all areas Tuesday night and sets up a strong ridge of High pressure across the UK on Wednesday and Thursday with sunny spells and warm conditions for all.

 

By Thursday the ridge will of slipped a little South and progressively cloudier conditions will reach the NW as an increase of Atlantic Westerlies is shown here. The South though should maintain fine and dry conditions until the weekend.GFS then shows a weak trough sliding South over the UK next weekend with a further band of cloud and light rain, clearing later as cooler air follows down behind it. High pressure is then shown to build strongly over the UK during the course of the following week with warm and sunny conditions likely for all. By midweek the cell elongates north/South down the north sea and eventually Scandinavia allowing more of a Southerly or SE breeze to develop by the second weekend ahead of a trough which moves into the UK and brings some showery rain before we end up where we are now with High pressure NE and SW of the UK killing the trough and leading to quiet and benign conditions to end the run.

 

The GFS Ensembles show a period of sustained normality in uppers across the South over the coming week while the North sees more variability as weak fronts cross by. The general consensus remains for the weather to remain on the warm side of average in the second half of the output even in the North with little rain in the South throughout though at least some will affect the North at times, especially the far North.The Jet Stream continues to show the flow riding High over the Atlantic well away from the UK. It does occasionally turn South down over the UK as troughs sink down the North Sea with a slow trend to sink the flow slowly South on a West to East axis towards the UK right at the end of the run.

 

UKMO today shows High pressure to the West of Ireland with a NW flow over the UK. benign and settled conditions look like continuing towards the South and West though cloud amounts could be quite large at times. The north and East could see cloud thick enough at times to give rise to a little light rain over the far North with temperatures just on the warm side of average in the South and close to average in the North.The Fax Charts show a trough slipping SE midweek weakening to nothing as it reaches the South with another set approaching NW Britain later in the week. With shallow high pressure close to the South of the UK the weather should be fine away from the NW where a little rain is likely by Thursday. Cloud amounts could be rather large at times as the cloud from the old trough from midweek is likely to be caught up in the airflow but temperatures in the South should remain good.

 

GEM today shows a vigorous Low developing to the North of Scotland at the end of the week and spreading it's influence towards the South and East over next weekend as winds freshen from the West or NW over all areas. This would inevitably bring cooler conditions first for the North and then for the South too by the end of the run as bands of cloud and rain on Atlantic gradually push further and further South to all areas in association with Atlantic fronts.NAVGEM today shows pressure falling to the North as well by next weekend with something of a trough making it's way SE across all areas at some point next weekend with at least a little rain in the South and maybe more in the North. It would gradually become cooler everywhere with a freshening West or NW wind especially in the North.

 

ECM today shows this same deep Low up to the North of the UK at the end of the week before it sinks SE down the North Sea with an Autumnally cool  and strong NW flow affecting the North and East next weekend with showers in places with even the South and west seeing a notable drop in temperatures for a time. ECM then redeems the situation at the start of the week that follows with High pressure building across the UK again with fine and warm weather returning for all with chilly and misty nights likely.In Summary today there is a mish-mash of outputs this morning. If it's fine weather your after then GEM isn't for you as it's the most extreme in bringing cooler and almost Autumnal conditions across the UK next weekend and the following week as it shows the Jet stream pulled South.

 

All other output does indicate the chance of a deep Low developing to the North of the UK by next weekend with ECM too bringing this into play for the UK too with cool and strong NW winds and showers for a time next weekend as it moves it down the North Sea. There is then some redemption for fine weather fans thereafter as both GFS and ECM bring High pressure back across the UK with fine and sunny weather developing for all with warm days and chilly, misty nights. It has been a trend over the past few days for the models to move away from the mouth watering charts of a few days ago with days of endless blues skies the only prospect to something more moderate in nature but in all honesty there remains a lot of dry and fine weather still to be enjoyed in today's output, especially if you live towards the South and SW. We just have to be prepared to expect more cloud and a little rain now and again and realise to ourselves that we are now entering the Autumn season so must expect some rather cooler weather at times when some rain is possible and the ever darkening mornings and evenings are gathering apace. 

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

Edited August 25, 2013 by Summer Sun

[Frosty.]

 Bluearmy last night that showed facts on model verification and the definition of a meaning.

whilst not mentioning all the overwhelming support for a warm settled outlook.

[Bottesford]

Lets keep it on topic and about what the models are showing please chaps - keep the preference chats to other threads!

[Jezzer]

Yes, how dare anyone post/talk about anything other than heatwaves or high pressure dominated charts.

People can discuss anything the charts show, it is the model output discussion after all.

I prefer Winter but I love Summer also. How about a bit of realism on outlooks and respect for everyone who makes a contribution to this thread? You can't label someone a coldie just because they have posted a chart that is not banging on about fantastic Summer weather.

Great posts from John Holmes and Bluearmy last night that showed facts on model verification and the definition of a meaning.

I'd agree, that's what makes this forum so interesting, there's a real mixture of weather fans with totally different preferences (I love cold snowy conditions in winter and love heatwaves in summer) but I think Scorcher has a point re. Matt's comments, throughout the summer I can't recall seeing him tweeting with excitement about high pressure, he does seem to prefer cyclonic conditions.

 

Anyway, all good fun this model watching. 

Edited August 25, 2013 by Jezzer

[BLAST FROM THE PAST]

Hi folks

Back from my sabbatical, camping trips and fabulous holiday in Menorca.  ECM looks like bringing a very autumnal feel end of the month but GFS doesn't want to buy it.  So good to see that nothing has really changed on here model and coldie/warmie camps wise :-) 

Anyway looking forward to the months ahead.  Will pop in during the week but got a lot of resumez de normal to do !!!

 

BFTP