Model Output Discussion - 1st July Onwards 18z--->

[knocker]

This morning's GEFS is pretty much in agreement with the 8-14. A look at the latest EC32 update makes rather more of the Greenland trough travelling east during this period probably impacting the UK, certainly the north. but the month progresses and into August it's looking at more influence from the Azores and would be a fairly pleasant prognosis if it comes to fruition.

http://www.tropicaltidbits.com/

 

[Frosty.]

The best thing I can say about the Gem 00z this morning is that it becomes warm for most of the run and occasionally very warm / hot in the south/southeast, temps next week generally mid 20's celsius across the southern half of the UK but high 20's c for a time in the SE later next week. It's not a settled run, humidity increases at times but there would be spells of very warm sunshine but also with outbreaks of rain / showers, some heavy and thundery.

Edited July 10, 2015 by Frosty.

[Summer Sun]

UKMO shows the potential for some thunderstorms next week with pressure fairly slack

 

 

Fairly warm in the south but more average the further north you go

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 08:00 ON FRIDAY JULY 10TH 2015.

 

THE CURRENT GENERAL SITUATION A cold front will move East over the UK late today and tonight with a SW flow across the UK tomorrow ahead of more troughs approaching the SW late tomorrow.

 

http://www.wetterzentrale.de/pics/Rtavn001.gif 

 

MODELS-2 WEEK HEADLINE Changeable with some rain at times but driest in the South with some short warm spells at times.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast continues to show the flow between 50 deg N and 55 deg N over much of the coming reliable period mostly West to East across the UK. It blows quite strongly for a time through the weekend and start to next week before weakening slightly and tilting more NW to SE for a time. There is then some suggestion that the flow may become more disorganized and less potent late in the period.

 

http://www.netweather.tv/index.cgi?action=jetstream 

 

GFS OPERATIONAL The GFS Operational Run today could be a lot worse given the Jet stream synoptics. The general theme of High to the SW and South and Low to the North and NE remains with Westerly winds veering NW next week. Some rain from passing troughs will inevitably occur with the North being affected by these most while the South only sees occasional and small amounts of rain. Then later in the run pressure builds strongly from the SW to cover the UK with fine and very warm or hot conditions extending to all areas to end the period.

 

http://www.wetterzentrale.de/pics/Rtavn1441.gif

 

http://www.wetterzentrale.de/pics/Rtavn3841.gif 

 

THE GFS CONTROL The GFS Control Run is rather different with regard to later next week hence Week 2 being rather different too. There is more development of a wave Low later next week which crosses NE over the UK giving rain and showers for all before the pattern resets with High to the SW and Low pressure to the North. The South would then become largely fine and bright with some warm weather at times while the North continue with Westerly winds and occasional rain.

 

THE GFS CLUSTERS(14 Days) The GFS Clusters at 14 days this morning remain indignant that High pressure will be the dominant factor with regard to the UK weather in two weeks time, centred down to the SW with varying degrees of extent of a ridge from it across the UK giving weather ranging from fine and warm conditions by the vast majority of members while others show a stronger NW flow with some rain or showers chiefly across the North

 

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

 

UKMO UKMO this morning shows a Westerly flow over the weekend giving way to very slack pressure gradients across the UK next week. With Low pressure aloft there could well be some heavy showers and thunderstorms breaking out almost anywhere. It should be quite warm in the South and less so in the North

 

http://www.wetterzentrale.de/pics/Rukm1441.gif 

 

THE FAX CHARTS The Fax Charts show troughs crossing East over the UK in the coming days with some rain at times. A chain of trailing fronts then look like affecting the UK to start next week with rain coming and going with generally very changeable conditions, even in the South.

 

http://www.weathercharts.org/ukmomslp.htm#t120.

 

GEM GEM today shows a slack pressure gradient too early next week before a developing Low pressure to the SW moves North and deepens and resets the generally NW/SE split later in it's run with SW winds for all and rain at times in the NW while the South and East see more dry, bright and at times quite warm weather late in the period.

 

http://www.wetterzentrale.de/pics/Rgem2401.gif 

 

NAVGEM NAVGEM today shows no governing weather feature across the UK next week with slack Low pressure and equally High pressure ones floating about around the UK delivering some dry and bright weather but as with UKMO some heavy and in places thundery slow moving showers too, almost anywhere at any time.

 

http://www.wetterzentrale.de/pics/Rnvg1681.gif.

 

ECM ECM today also delivers a period of fairly slack pressure early next week and with warm air close to the South and instability aloft some thundery showers could occur on this run too. Later in the week a more distinctive and cooler NW flow takes hold with further showers in places but mostly through the daytime's and in the North and East with some reasonable conditions then likely across the South and West.

 

http://www.wetterzentrale.de/pics/Recm2401.gif

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last evening looks broadly similar to the evolution of this morning's operational run for 10 days time so one should assume that many members support this type of evolution.

 

http://www.wetterzentrale.de/pics/Reem2401.gif 

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS There is still no definitive trend detected from this morning's output with all models playing around with rather complex and often slack synoptics.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM. This morning's verification statistics show ECM leading the way at 3 days with 96.0 pts followed by UKMO at 95.2 pts and GFS at 94.7 pts. At 5 days ECM is stll king at 85.1 pts followed by GFS at 81.9 and UKMO at 81.3 pts. Then at 8 Days ECM still leads at 53.9 pts over GFS's 50.0 pts. Finally at Day 10 ECM leads GFS at 32.7 pts to 30.2 pts from GFS.

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png 

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.prig

 

MY THOUGHTS There still remains a lot of uncertainty between the models in the exact details of the weather through next week and beyond. A lot of the problem lies as I have said before with a Jet flow that ebbs and flows far further South than is normal or ideal for this point of Summer. In addition the weather features affecting our weather are generally quite weak and when they are weak their movement and track is less predictable and it's that models are finding it difficult to pin down at the moment. It is further complicated next week as the Jet flow looks like weakening making incoming weak Low pressure stagnate near the UK which could throw up some days of strong convection next week with very slow moving showers for a time. GFS is quite keen on developing a stronger and deepening Low pressure as it transfers NE across the UK next week with wind and rain for all as it goes before pressure builds from the SW with the chance of some fine and warm weather for the South at least and if the operational is to be believed all areas later when it would become very warm or hot. The other models look less interested in this move with ECM just gently feeding the UK back into a somewhat showery NW flow late next week and weekend with the South and West seeing the best weather away from the daytime convection and thundery showers which could continue across Northern and Eastern areas each afternoon. So a complex set of charts lead to very difficult forecasting with confidence still very low in any one interpretation verifying. Nevertheless, there is something for everyone in todays output but which areas end up having which weather type shown remains a lottery at the moment but all I can say again this morning as I have for many days past recently things could be a whole lot worse, especially in the South where there still looks to be some good weather to be found at times. 

 

Next update from 08:00 Saturday July 11th 2015

[Frosty.]

The Gfs 00z looks much more settled through low res with high pressure having the upper hand and only a brief interruption to the settled picture, the run ends on a high note with an intensifying anticyclone over the top of the UK bringing perfect summer weather..and speaking of perfect weather, for England and Wales today it's perfect summer weather with warm / very warm and sunny conditions and temperatures in the mid to high 20's celsius, warmest in the SE.

Edited July 10, 2015 by Frosty.

[knocker]

There isn't good agreement between the anomalies this morning so confidence is low vis the evolution. The GEFs paints a better picture because in the ext period the ECM tends to deepen the trough Greenland/Iceland and run it east thus not allowing the Azores ridge as much room for expansion as the GEFS. The EC32, also takes this line which is not perhaps surprising. Having said that I'm looking forward to a cracking last week July and first week of August.

http://www.tropicaltidbits.com/

Edited July 10, 2015 by knocker

[Tamara]

As the Pacific signal fades, and there is de-amplitude in the MJO signal, we can expect the extra tropical Global Wind Oscillation to accordingly de-amplify from its Phase 5 to 7 orbit and head back towards Phase 0. This is the phase of greatest uncertainty - much as it was in June

 

Much like during the middle of June, when the synoptic pattern was fairly similar to the coming week to 10 days, there is little point in examining NWP intra day output in too much detail - as uncertainty clouds the precise pattern in the post MJO spike period.

 

What is unlikely is any widespread sustained cooler unsettled spell.

 

A boundary will continue to exist just south of the upper trough that divides the cooler North Atlantic air and the very warm and humid continental air. Another warming trend is not meant to automatically imply a return to heatwave conditions, but this boundary is never going to move very far, and as and when eventually the upstream pattern slows and stalls just a little, it will be enough to bring very warm conditions back to the south

 

 

No apologies for quoting this particular relevant section of a previous post because 5 days later things are moving on as anticipated above

 

The period of indeterminate tropical and extra tropical forcing on the NH pattern is coming right towards the 10 day radar. No surprise to see something of a dogs breakfast synoptically in the various models, which, as suggested would probably be the case, is not worth analysing in any great detail

 

Global Wind Oscillation and MJO both on their way to the inner circle - ahead of next MJO convective wave cycle

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfsgwo_1.png

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_small.gif

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/NCPE_phase_21m_small.gif

 

This puts us back to a similar situation to a month back and the shoal of fish analogy wrt NWP.

 

Some of the modelling is playing around with further potential plume situations. Until we see the way ahead, with greater confidence, from the inner circle weak signal forcing on the NH pattern we are unlikely to see anything meaningful however with the pattern probably remaining too flat until there is further upstream forcing.

 

This means that another watching brief is in progress over the next week to 10 days to see how things look to re-set themselves on the other side of the global hemisphere.

 

The height anomalies to the north are likely to fade with time, as the high amplitude phases 7 and 8 give way to an eventual weak signal picked up towards the Indian Ocean - MJO Phase 1/2 as the next tropical forcing cycle begins.

 

It is a minefield trying to predict future MJO activity for the professionals, let alone any of us ordinary folk - but, applying a splash of credible meteorological logic, the basis of the now solid Nino ocean/atmosphere coupling on weather patterns makes it likely, the next time around, the signal response will rather by-pass the Indian and Western Hemispheres and transpose onwards and strengthen in amplitude as tropical thunderstorm activity progresses eastwards towards and through the Pacific.... - with renewed positive frictional torques and Atmospheric and Angular Momentum spiking upwards again.

 

The GWO at the same time responding and emerging from the inner circle and towards Phase 4/5.

 

What does all this mean for us in simple terms synoptically? 

 

Further sharpening out west of the Atlantic trough and another downstream Euro ridge. Those JAS GWO composites previously linked give some confirmation of the corresponding likely upper height anomaly pattern to shape this

 

GEM likely too progressive with its heat-seeking, but quite conceivably on the right track for the extended period later this month - timing far too early to know.

 

More confidence required on all this - we await developments, which will be better known about a week or so from this time  .

[Man With Beard]

Quite a few hotter runs for this time next week on the latest GEFS (mostly brief hot spells):

http://www.meteociel.fr/modeles/gefs_table.php?x=306&y=141&run=6&ext=fr&mode=0&sort=2

[Frosty.]

The Gfs 6z has an Epic low res with high pressure gradually building in with dry, sunny and increasingly warm weather followed by a lovely spanish plume with another heatwave as the jet buckles, much as it did recently. I firmly believe the last 7 weeks of the meteorological summer will produce more plume events and plenty of high pressure.

Edited July 10, 2015 by Frosty.

[mushymanrob]

Gfs 12z looks very very average. An unsettled, mixed bag, some warmth, some cool, some rain but not overly wet, some dry.

Not too bad but nothing special.

[Milhouse]

A short spell of heat has appeared on the GFS 12z, and was there, to a lesser extent on the 6z too. So perhaps something of interest to come mid week. Generally a warm but changeable/unsettled outlook sums up the coming week with Wednesday looking the best day for dry weather.

 

[Frosty.]

The Gem 12z shows some fine and very warm / hot conditions at times, especially for the south and east with high pressure building to the east. I think there would be a chance of T-Storms in the s/e as well as the best of the sunshine and dry weather.

Edited July 10, 2015 by Frosty.

[cheese]

A short spell of heat has appeared on the GFS 12z, and was there, to a lesser extent on the 6z too. So perhaps something of interest to come mid week. Generally a warm but changeable/unsettled outlook sums up the coming week with Wednesday looking the best day for dry weather.

 

That chart looks horrid for our part of the world Milhouse - but I was trawling through GFS max temps and in general it shows highs of 20-22C most days with only one or two days below that, so just what you would expect from July here. Nothing much to complain about IMO.

[Milhouse]

That chart looks horrid for our part of the world Milhouse - but I was trawling through GFS max temps and in general it shows highs of 20-22C most days with only one or two days below that, so just what you would expect from July here. Nothing much to complain about IMO.

 

The GFS has a big blob of rain and very suppressed temps for northern England next Thursday, and infact it does look dire for our part of the world. But as its too early to tell where any rain would be, expect the temperatures to be different to whats being shown. The general idea is for a warm up of sorts from midweek.

[Milhouse]

And the ECM 12z is going the same way too. High pressure initially over the UK on Wednesday, followed by low pressure to the west sending some heat northwards for Thursday.

 

[Frosty.]

The Ecm 12z is warmer than the 00z, especially further out and its only the far n/nw which has any cool conditions between T+96/120 hours. The s/e look warmest with a pulse of very warm and humid air from the continent pushing up across the s/se later next week, close to 30c 86f for a time, the southeast is warmest and also looks like having the best of the sunshine. In my opinion the Gem 12z is the best run with HP building strongly to the east (charts I posted on previous page) with the hottest conditions but I think a plume is looking a good bet, at least for the south during the second half of next week.

[knocker]

Just out of interest the Latest North Atlantic SST anomaly

http://www.tropicaltidbits.com/

 

[bluearmy]

Last few runs of the extended ECM eps show the western extent of the scrussian trough engulfing nw Europe . That's keeps the theme going of systems running across us form w to e. Whether that can be more sw/ne or ends up w/e will dictate if the se of the UK can escape the worst of things.

Edited July 10, 2015 by bluearmy

[damianslaw]

Approaching what I call peak summer period and the charts are showing very average standard summer fayre, in what so far barring the oddity of 1 July is turning into a very average standard summer.

Edited July 10, 2015 by damianslaw

[knocker]

The GFS has the depressions tracking NE into the UK next Weds/Thurs dragiing some hot air into eastern France once again.

http://www.tropicaltidbits.com/

 

[Frosty.]

The Ecm 00z shows the south hotting up for a time later next week, next Friday looks a scorcher with low 30's celsius for the s/se and still very warm in the SE into next weekend...and then the ecm says hey..let's have another reload of heat, nice charts

Edited July 11, 2015 by Frosty.

[mushymanrob]

Approaching what I call peak summer period and the charts are showing very average standard summer fayre, in what so far barring the oddity of 1 July is turning into a very average standard summer.

 

true.... but to be fair, 'average' isnt bad!

[Frosty.]

The Gem 00z also has a surge of heat later next week, slightly delayed compared to ecm but thereafter becomes more mobile although still warm in the south. The gfs 00z is not interested but the Ecm 00z is very interested in reloading the very warm / hot and humid continental conditions into the following week. It's a potentially very interesting set up next week imo.

[Captain Shortwave]

This coming week is a strange one, a weather front will persist over the south during the first half of the week. To the north it will be brighter and cooler with showers, the south seeing a lot of cloud, but with 850s of 8-10C then it will feel warm and humid, if the sun breaks through then it could get very warm at times.

The latter half of the week offers something much warmer and more widespread as low pressure upstream tries to sink further south towards the south west of the UK, offering a southerly flow briefly before that very low pushes north eastwards giving the risk of thunderstorms as it passes through. The ECM looking most bullish about this evolution.

Cracking little chart if you like your plumes, the 20C isotherm approaching the UK again  with low pressure ready to push northwards through the UK on Friday bringing the risk of thunderstorms.

 

Other models vary on this

UKMO

Flatter hence less heat 

 

GFS

The solution is much quicker, that said I am unsure on how well the GFS is going to handle these delicate features.

 

GEM

Looks a little over the top in the blocking which could skew the evolution somewhat.

 

At the moment I think a middle ground between the UKMO and ECM is likely for the end of this coming week. Interestingly the ECM wants to repeat this set up during week 2.

 

So overall the coming week looks warm in the south, with a mix of warm and humid but fairly cloudy days, but also a couple of sunnier and very warm days. The north sees more of a traditional mix with near normal temperatures.

[Man With Beard]

Not sure I agree with this "average" summer idea, not if the GEM/ECM are onto something. There seems to be something in the atmosphere that is conducive to mid-Atlantic troughing - this week, its almost as if the models have defaulted to that position (at times) in the absence of other strong drivers. We know that the route to extreme heat over the UK is this very scenario as it creates a southerly pull from the regions like Spain. So whilst sustained heat is not as likely as if we had a July 2013 style UK high, extreme heat becomes not a certainty but more of a risk.

The current charts from ECM, both 12z and 00z, show scenarios not far off bringing those mid-30s to the UK again. Certainly the French will be wondering what on earth is up with the weather this summer.

So average? maybe it will be, but plenty of room in the models for something more exceptional, yet again.

Edited July 11, 2015 by rjbw