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

[johnholmes]

Why are the 500 mbar anomaly charts never available? No matter when I check, it always has the usual message about updating etc

Are they now only available if you pay?

Is there another place to read them?

 

i use these links

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

and 

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[Dean E]

All models are pretty much in line with the midweek set up of Low pressure crossing to our north bringing some rain and/or showers to most areas. Temperatures around average across the board.

 

However, the late week 'plume' is still showing with both GFS 12z and ECM 12z both toying with the idea around the 10th now.

 

GFS 12z

 

 

 

ECM 12z

 

 

 

Both producing another southerly plume with 16c uppers just reaching the South Coast. So from this we could expect temperatures returning into the very warm category.

 

Beyond next weekend and into FI, GFS hints at a 'rinse and repeat' with ridge moving across the Atlantic and cooler conditions, then another shot of warm continental air. ECM goes with sticking with the warm theme and throwing in some Lows towards the south over the near Continent.

[knocker]

The GEFS anomalies tonight. After next week retrogress the Atlantic trough and then disappear it leaving HP over the Pole and a very flat pattern, apart from a ridge western Canada and weak HP over the UK, from the Pacific to the UK. Indications of a fairly benign, pleasant outlook, but why do I have feeling of waiting for something to happen?

http://www.tropicaltidbits.com/

Edited July 4, 2015 by knocker

[Man With Beard]

Latest NOAA 8-14 dayer:

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

Still strongly suggesting an Atlantic trough up against a Euro high, like last night. Which is pretty much at odds with the ECM op, which ends very flat. Will be interesting to see how the ECM ens sits later, as I would expect more buckling in the pattern close to the UK if the NOAA has got it right.

[Frosty.]

The Ecm 12z gives the south a brief plume later next week with temps around the mid 80's F for a time and widely into the mid 20's c across the rest of England and Wales. Looking at next week in general, Monday will see a band of rain pushing in from the west followed by sunshine and showers in a breezy and fresh Atlantic air flow, similar bright and breezy showery mix on tues/wed and feeling cool out of the sun but a ridge of high pressure from the west brings a more settled Thursday and HP to the east of the BI by Friday enables the very warm continental air to drift north, it's brief but Saturday is very warm too in the east/southeast and further ahead, the south does best for largely fine and pleasantly warm conditions with temps into the low 20's c on this run.

[Frosty.]

The GEFS 12z mean doesn't look too shabby at all, at least across the southern half of the UK as it indicates the Azores high ridging across the south at times with plenty of fine and warm weather and potential for very warm air from the continent to make occasional inroads into the south, generally less settled and less warm further north/northwest.

[knocker]

Major differences between the anomalies tonight so confidence not high. The ECM is favouring the NOAA take on it so the more likely outcome with the upper trough to the NW meaning LP will probably be more influential in the westerly flow backing NW in the eastern Atlantic. Needless to say although the likely outcome it still remains to be resolved.

http://www.tropicaltidbits.com/

 

[knocker]

An overview of this mornings GFS

 

Quite an interesting run because although the overall pattern is still rather fluid after the midweek cool period high pressure, except for a short period is far more influential. except for the NW of the British Isles. Thus from next weekend temps tend towards the warm, sometimes very warm, until the end of the run. The exception to this being the north west. A snapshop with a couple of charts courtesy weatherbell but note this is just a snapshot of one run.

 

Regarding the GEFS anomalies it has backtracked completely on yesterdays 12z and retained the trough to the W although it still loses it later.

http://www.tropicaltidbits.com/

Edited July 5, 2015 by knocker

[knocker]

Needless to say the ECM is not happy with the GFS and continues to track the depressions further south thus far more unsettled, As mentioned last night there is still uncertainty concerning the evolution and one suspects it centres around the upper trough to our west.

[Man With Beard]

Bit of a split in the models today - a shorter warmer spell still on for the weekend - beyond that, UKMO and ECM look as if they will go flat - and combined with heights to the north, that may mean the trough being forced straight through northern parts, so I'd be a bit concerned about the mid part of July if you live there and are hoping for some summer weather.

There is some hope for northern areas in the GFS, though - a more buckled pattern means the summery weather reaches these areas at times too. Not masses of support in the ensembles, but it does have the support of the control run on warmer incursions nationwide:

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=264&mode=0&carte=

Edited July 5, 2015 by rjbw

[johnholmes]

The 3 main anomalies are not idential with EC breaking ranks and showing no ridging or +ve heights with upper troughing the main feature and air being sourced from the Gt Lakes area. The other two (NOAA and GFS) are more alike and would suggest a better outlook. No consistency means no major confidence in the 6-10 day outlook for now. The betting must be on the two against the one but on a synoptic level EC generally wins out at 6-10 days over GFS?

[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 SUNDAY JULY 5TH 2015.

 

THE CURRENT GENERAL SITUATION An unstable SW flow covers the UK with showery troughs spreading NE through the day and more Atlantic fronts reaching the West tomorrow moving East.

 

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

 

MODELS-2 WEEK HEADLINE Changeable with some rain at times especially in the North and West. Warm in the South at times.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the Jet Stream flowing NE or East over the UK for the next few days before veering NW to SE midweek. Having ridged North over the UK later in the week the flow then settles further too the North on an easterly track between Scotland and Iceland. At the end of the period the flow breaks up and become ill defined.

 

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

 

GFS OPERATIONAL The GFS Operational today is best described as showing a very changeable period over the next few weeks with some more unsettled and cooler phases with rain at times mixed with some fine and warm periods under High pressure crossing from the SW or West on several occasions through the period. The most unsettled weather will be in the North and the warmest conditions will be in the very warm category at times in the South.

 

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

 

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

 

THE GFS CONTROL The GFS Control run although slightly different in day to day events maintains a very similar and changeable picture. A lot of dry and occasionally very warm weather looks likely in the South but this will be interrupted by showery and perhaps thundery troughs displacing the warm conditions at times for something somewhat cooler with the process repeating again thereafter especially over the North.

 

THE GFS CLUSTERS(14 Days) The GFS Clusters today show a split with some showing a slack northerly with High pressure out in the Atlantic with some heavy showers floating South while the remainder maintain High pressure to the SW with some fine weather while a few bring Low pressure closer to the North with the westerly flow brisk and unstable across the UK.

 

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 today shows a cool phase of weather between Tuesday and Thursday with a mix of sunshine and showers, heavy and thundery by day. A ridge of High pressure is then shown to build on Thursday and Friday with warm and sunny weather for a time especially in the South before another thundery trough moves East into the warm air next weekend returning cooler air off the Atlantic once more behind it.

 

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

 

THE FAX CHARTS The Fax Charts show a series of troughs crossing West to East over the UK this week with progressively cooler and breezy weather in two. Pressure builds through Thursday and Friday as a ridge crosses East with a warm front approaching the West of the UK from the West by the weekend. 

 

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

 

GEM GEM today looks quite good for the South as a lot of warm continental air periodically wafts up across the UK but made temporary by troughs of potentially thundery Low pressure soon following each surge of warmth. The North lies in the more changeable and traditional Atlantic air for most of the period with rain at times.

 

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

 

NAVGEM NAVGEM also follows a similar theme of warmer and drier weather late in the week following the early to midweek rain and showers. It too then brings a potentially thundery trough East to give some rain for all at the weekend before fine weather returns soon after.

 

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

 

ECM ECM today shows nothing really significantly different than the rest with very warm air over the continent tantalizingly close for all of the time and occasionally wafting up into Southern Britain only to be met by occasional opposition from Atlantic breezes and fronts with potential rain, thundery at times.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart this morning looks like bringing the influence of Low pressure up to the North and NW of the UK rather closer in giving a greater risk of rain and showers across the UK with warmth still holding on in the SE.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend today looks in favour of South and East as best for warmth and occasional thundery rain while the North and West stand greatest risk of Atlantic borne rain at times.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The current verification statistics for the past 31 days shows ECM leading the way at 3 days with 96.0 pts followed by UKMO at 95.1 pts and GFS at 94.8. At 5 days ECM  leads GFS at 84.8 pts with GFS at 81.8 pts and UKMO at 81.8 pts too. At 8 days ECM clocks in ahead of GFS at 47.7 over 46.1. Then at Day 10 ECM remains ahead of GFS at 31.2 pts to 26.2 pts.

 

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 We appear to have become in a set pattern across the UK for the coming two weeks. The basics of this is Low pressure to the North and NW far too close and very warm air locked in over Continental Europe and this pattern looks like persisting for some considerable time. Of course this doesn't mean that the same weather will occur over the UK day to day as the boundary zone between the heat of Europe and the cooler unstable Westerlies undulates across the UK for much of the period. So it looks like being cool and breezy for a time this week with some heavy showers before High pressure builds later in the week allowing some of that warmth over nearby Europe back up over the UK. It quickly becomes attacked by either thundery Low pressure from the South or West as the Atlantic winds regain some territory again next weekend. The longer range charts show little sign of altering this battle over Week 2 either with further pulses of warm and fine weather especially over the South before the next push of Atlantic air brings another threat of thundery rain through most parts. The one thing of importance to note as despite some negativity shown in my report this morning for much of the time in any one place the weather should not be that bad especially in the South with thundery rain possibly heavy though brief with a lot of fine weather in between. In the North things might be a little too much Atlantic based to share in much of the South's warmth but even up here some decent days are possible and indeed more than likely. Overall I think that temperatures will remain near average in the North after a cool blip in the middle of this week while the South sees the near average temperatures up to the middle of this week rise into the warm and very warm category again towards next weekend and probably again on occasion through Week 2.

Edited July 5, 2015 by Gibby

[knocker]

The 3 main anomalies are not idential with EC breaking ranks and showing no ridging or +ve heights with upper troughing the main feature and air being sourced from the Gt Lakes area. The other two (NOAA and GFS) are more alike and would suggest a better outlook. No consistency means no major confidence in the 6-10 day outlook for now. The betting must be on the two against the one but on a synoptic level EC generally wins out at 6-10 days over GFS?

 

The GEFS seems very unsure how to play with this trough John if the last few runs are anything to go by unless I'm missing something.

http://www.tropicaltidbits.com/

[Tamara]

The overall outlook is not really changed much at all since the last post a few days back.

 

In response to a record July high amplitude Phase 7 MJO convective signal in the East Pacific, a broad belt of zonal westerly winds has been added across the Equator and sub tropics. Atmospheric and Angular Momentum consequently driven poleward with net easterlies set to be added at higher latitudes in the Northern Hemisphere.

 

This supports the synoptic pattern indicated for the coming week with an increased height anomaly to the north of a broad Atlantic/Scandinavian trough and the cooler rather more Atlantic influenced set-up as discussed recently.

 

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

 

Updated GWO forecasts continue to look very plausible in this respect

 

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

 

This in turn still supports the sequence suggested in recent posts of a similar passage of weather to what was seen during June, prior to the heatwave plume.

 

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.

 

Essentially though the most likely evolution continues to be the cooler more changeable theme this week, followed by something of a N/S split, and another warming trend gathering pace from the south as time progresses.

 

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

 

The GFS is often very good at picking up extended trends, and I think is anticipating that next re-set phase. Any suggestion of return back towards GWO Phase 5/6, which is quite possible, will increase support for stalling the Atlantic trough further west more and across the board ensemble support for another warm-up will appear very quickly.

 

Therefore Knocker is correct in saying that that the Atlantic trough is the key. Much like the trough was during June when at face value it seemed that the pattern was destined to stay rather flat....

 

Whilst anticipating a very logical longer term evolutionary signal, the mistake the GEFS anomalies might be making is being rather progressive with holding back the Atlantic trough, but at the same time I would not be taking the Euro stance of the flatter more progressive eastward trough pattern currently suggested as any signal for prolonging the cooler and more changeable interlude beyond the sort of transition phase we saw during June.

 

Its worth remembering that the ECM operational, and to a degree the UKMO, were the most progressive with an eastward upper trough pattern during June and the GFS was first to spot the trough backing NW away from the UK

 

Edit: ECM operational a wetter and breezier solution to the mean on the updated London ensembles. This supports the idea that it is probably too progressive with the extensity of the trough to the north around days 9 and 10.

 

http://www.weathercast.co.uk/meteo/eps/ensemble-rrrcum-london.gif

 

 

http://www.weathercast.co.uk/meteo/eps/ensemble-ff-london.gif

Edited July 5, 2015 by Tamara

[bluearmy]

The extended ens anomolys seem uncertain in our locale. Blocking north and nw of Greenland. Troughing Eastern Scandi and into Russia. Mainland Europe seems to stay with reasonably high heights. As others have mused above, how the Atlantic trough interacts with the scrussian trough will dictate how far se its influence affects. The safe prediction would be changeable on a nw/se basis.

[Polar Maritime]

Yes the Models have been showing a N/W S/E split for some time now. And this broad brush theme continues this morning with some quite warm days for the South with showers at times as High Pressure continues to wax & wane, While the North remains a little cooler and unsettled at times, Overall a standard British Summer pattern.

 

[phil nw.]

Many posters this morning highlighting a return to more normal UK conditions going forward as the last of the almost sub-topical heat and storms of the last week finally move away into the continent.

The Atlantic trough becoming more influencial now and a glance at the latest fax for mid-week shows a much cooler spell as low pressure extends towards Scandinvia turning the winds more north of west briefly.

 

however the heights remain close enough over Europe and ridging from the south should still give us enough decent weather from time to time so not the worst outlook for many-just not the heat we have had recently and more what we would expect in an average Summer.

A look at the Naefs and ECM height anomaly forecasts for day 5 and  10

 

would suggest little change well into July with, as others have said,a north/south split ongoing.

The Arctic ht anomaly and the Azores/Euro heights locking in mean -ve pressure across the E.Atlantic towards Scandinavia to the north of the Uk for the foreseeable.

Edited July 5, 2015 by phil nw.

[Frosty.]

There is no shortage of fine and very warm weather on the Gfs 6z, especially for the south and east with regular incursions of heat from the near continent and generally fine and warm at other times. The north west of the UK is more unsettled and cooler but occasionally warm and fine. This is a very acceptable run with plenty of warmth and sunshine.

Edited July 5, 2015 by Frosty.

[Methuselah]

Indeed, Karl...Plenty of opportunity for plumes (plumelettes,? minor plumescences?) to bring some added interest to the SE especially. Next Friday night - Saturday morning might spring some surprises?

 

In other words: The interplay, between the hotter-than-average air to our south and the product of the relatively cold North Atlantic SSTs, has the potential to provide some quite campanologically exquisite skirmishing along the boundary layer between two so starkly contrasting airmasses as seem likely to pertain; and all this the vicinity of the UK??

 

In yet more other words: Not too far off what we should expect (perhaps a wee bit warmer) at this time of year...Interesting times are ahead.

Edited July 5, 2015 by Ed Stone

[Frosty.]

Indeed, Karl...Plenty of opportunity for plumes (plumelettes,? minor plumescences?) to bring some added interest to the SE especially. Next Friday night - Saturday morning might spring some surprises?

Agreed Pete, if anything like the 6z verifies, I would be very satisfied if I lived in the south because temperatures would regularly be into the 80's F and plumes bring the added interest/excitement of thundery outbreaks as we have seen plenty of in the last week....more to come hopefully.

Edited July 5, 2015 by Frosty.

[Methuselah]

Agreed Pete, if anything like the 6z verifies, I would be very satisfied if I lived in the south because temperatures would regularly be into the 80's F and plumes bring the added interest/excitement of thundery outbreaks as we have seen plenty of in the last week....more to come hopefully.

I just wish I could be as not-IMBY as you, Karl: all my thinking has always been largely centred around 'here'.

[h2005__uk__]

Judging from the current models, is there a chance that next weekend's plume could become a bit more notable?

[Snowman.]

Judging from the current models, is there a chance that next weekend's plume could become a bit more notable?

Depends how far west the low can back and how much air can be convected northwards but considering it's in the semi-reliable unlikely.

Edited July 5, 2015 by SN0WM4N

[legritter]

Judging from the current models, is there a chance that next weekend's plume could become a bit more notable?

Every chance at this range ,only needs Atlantic low to move further north the high modelled to be slightly higher in pressure and we could be in with a chance ,but before that some changeable weather but no wash out ,we had a good plume heres to the next ,cheers .

[Scorcher]

Yes this latest GFS run is a good one for the end of the coming week and into the weekend, with temperatures getting widely into the mid 20s again for England and Wales, cooler for Scotland though, particularly further north and west.

 

I imagine the SE would again threaten 30C over the weekend if this run came off. The GFS is sticking to its guns over this warm up from Friday onwards- it will be interesting to see what the ECM has to offer later on.