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

[Polar Maritime]

GFS shows a cooler N/W sometimes Northerly flow from around Wednesday onwards.

Edited July 18, 2015 by Polar Maritime

[summer blizzard]

With the lows looking to approach from further south, i fear it could be a wet end to the month.. 

 

[Man With Beard]

Anyone else thinking this month has been like an extremely long and drawn-out shipwreck? Started with the hottest 1st July day ever, I wouldn't be surprised if it finished with the coldest 31st! It seems every passing day has seen the potential for a proper settled summer spell has just ebbed away, and tonight, going by the ECM which in my opinion looks quite plausible, the jet is preparing to fire straight at us having threatened to do so for quite some time.

It's actually been a cracking summer so far on the south coast but I see it disappearing now after midweek, and for folks further north, hopes of anything decent in July appear wishful thinking more and more every day. The odd decent day will need to be grasped very firmly!

[knocker]

The ext GEfs and ECM anomalies continue to indicate a weakening of the upper trough and positive heights eastern Europe and more influence from the Azores HP although still keeping the flat zonal flow.

[mushymanrob]

deep fi i know, but this has to be one of the worst charts we could expect to see as july finished and august is about to start.  its hard to see where and azores high/settled weather will come from off this set up.
 

but thats fi, and the latest noaa 8-14 day anomaly chart ...



.... suggests the ecm @ t240  might be over stating the upper lows potency. as knocker says, its looking much flatter then recent charts, suggesting a move in the right direction?...

[knocker]

Looking at ext anomalies this morning still looking fair for the Azores tap dance, more so the ECM. as the GEFs still has a little niggling trough Iceland way. Still zonal and around average temps but dry and pleasant for all. Time for the worry beads.

[Gibby]

Rather later than usual but here's todays attempt at unravelling the spaghetti.

 

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 19TH 2015.

 

THE CURRENT GENERAL SITUATION. Relatively weak troughs of Low pressure will continue to run East across the British Isles on occasion in a moderate to fresh West or SW flow.

 

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

 

MODELS-2 WEEK HEADLINE Still rather changeable with some dry and bright conditions mixed with occasional rain or showers. Temperatures largely near average but possibly warm at times in the SE at first

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast keeps the flow undulating North to South across the UK in association with mostly Low pressure to the North and High to the South. The flow then weakens at the end of the period and becomes ill defined.

 

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

 

GFS OPERATIONAL The GFS Operational Run today shows the basic pattern of High to the South and Low to the North maintained for much of the period. The High to the South holds influence across the South more in the first week and again late in the period while an interlude of Low pressure to the North brings unsettled and cooler conditions to all districts for a time at the start of the second week.

 

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

 

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

 

THE GFS CONTROL The GFS Control Run is somewhat different in detail but more or less rings the same bells today as a mostly Westerly based pattern this week keeps the North/South divide going with some rain possible for all but more so in the North. Then after a pressure build across the UK with any rain then restricted to the far SW next weekend the pattern resets with a stronger build of pressure North across many parts of the UK at the end of the period. 

 

THE GFS CLUSTERS(14 Days) The GFS Clusters at 14 days seem to have shown High pressure out to the SW at the 14 day point for what seems ages now and today is no exception with the pendulum now having swung back towards a greater chance of fine and settled conditions across the UK as a ridge from it lies towards Southern Britain. There is of course around 25% of members who show a much more Atlantic based and unsettled pattern though in among the good runs.

 

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 West and then NW flow across the UK for much of this week, never overly strong and with the lack of any major weather systems across the UK through the period the weather can best be described as benign and mixed with some cloud and showers alternating with dry and bright weatehr with temperatures near or perhaps a shade below average in the North.

 

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

 

THE FAX CHARTS The Fax Charts this morning pick up on the finer detail the raw data doesn't show with weak troughs meandering East and NE at times delivering some cloud and light rain or showers with periods of ok conditions in a relatively slack and inactive Westerly flow across the UK especially later in the week.

 

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

 

GEM GEM today also shows a relatively slack Westerly this week with higher pressure never far away to the South or SW ensuring not too much unsettledness reaches down here. Late in it's run the pattern sharpens and a Low moves across Central parts delivering cool and unsettled weather with rain and showers to all districts to start Week 2.

 

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

 

NAVGEM NAVGEM today gives weak High pressure the largest say in conditions across the UK late  in the coming week with several days then when all areas could see some fine and dry if not overly warm weather. The pendulum swings back towards the risk of rain though in a weeks time as an equally weak Low pressure zone moves in off the Atlantic.

 

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

 

ECM ECM this morning shows a lot of upper cool pools of air around the UK over the coming week to 10 days which holds any chance of summer warmth away from our shores through the period. However, the changeable theme of conditions through this coming week will not be too dramatic across the South but by next weekend and the start of the following week it looks like all areas come under risk of rain and showers, equally in the South as the North with some quite cool air aloft some thunderstorms in daytime convective periods look possible.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night shows Low pressure over Scandinavia with winds from between West and North across the UK with a typical pattern of sunshine and showers in average temperatures at best most likely by Day 10.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The main trend from the models maintain a Westerly flow across the UK for the foreseeable future.

 

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 95.5 pts followed by UKMO at 94.9 pts and GFS at 94.1 pts. At 5 days ECM is stll king at 83.9 pts followed by UKMO at 80.5 and GFS at 80.3 pts. Then at 8 Days ECM still leads at 53.7 pts over GFS's 48.6 pts. Finally at Day 10 ECM leads GFS at 34.6 pts to 29.9 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 By missing a days model output I thought I might return this morning with something different to report but alas that seems not to be the case as the current pattern looks to persist for the most relaible part of the periods predictions over the next 5-7 days. That means a series of fronts crossing the UK each with their own brand of rain (often not much down here in the South) and periods of fresher Westerly winds with sunny spells and the odd shower, chiefly in the North. The synoptics that make up this pattern remain more or less in situ in the much less reliable time frame as well on todays output with perhaps a trend to shift things towards even cooler air wafting down over the UK under Low pressure which gradually resides more towards Scandinavia in Week 2 and setting up a NW feed and bottling any remaining European heat way South of our shores later. It has to be noted though that most output doesn't show any particularly nasty Low pressure areas or intense areas of High pressure either over the top of the UK with all in all a quite slack pressure gradient for much of the time across the UK. The resultant conditions at the surface will be extremely difficult to pin down especially locally in this setup but for the most part I think dry conditions should outweight the wet with the SW looking likely to score the best in this regime while the North ends up coolest and most prone to showers or rain. So while nothing dramatic to report today nothing particularly noteworthy in terms of heat and settledness either with little if any liklihood of seeing particularly warm conditions now this side of August. 

 

Next update from 09:00 Monday July 20th 2015

[seaside 60]

Without wishing to remind people.

However wasn't last August somewhat colder and wetter than average and a very disappointing month.

SO any charts produced cant be the worst ever.

[Polar Maritime]

Without wishing to remind people.

However wasn't last August somewhat colder and wetter than average and a very disappointing month.

SO any charts produced cant be the worst ever.

 

Very true.. Who said they were..? A long way to go yet in the Model 'World' before we have any consensus of what will unfold during August.

[Summer Sun]

GFS has another deep low lining up in just over a weeks time as it begins to move east it opens the door for northerly winds for a time

 

[Man With Beard]

http://www.meteociel.fr/modeles/gefs_table.php?x=306&y=141&run=12&ext=fr&mode=0&sort=2

This chart says it all. After the next 2/3 days, absolutely ziltch in the way of true summer warmth, and this is for London. Considering its the last 10 days of July, that's a horror show for those wanting a beach day. Having said that, the south coast won't feel too bad on any winds north of west, so maybe beach is indeed best.

Mind you, tonight's ECM throws some crumbs out. A decent little ridge of High Pressure could bring a sunny weekend for most - and possibly a warm one, considering the likely lack of wind

Edited July 19, 2015 by rjbw

[legritter]

where is everyone ,yes there is life apart from weather models etc .

just had a look at charts and certainly no big heatwaves on offer .

but an increasing risk of rain enough to top up the water table ,Gfs brings in some low pressure areas and soon the ECM will be out so lets see if that comes in with todays gfs runs .

A realy mixed up summer so far ,pretty dry here in west country ,and i was down the south east recently and parched fields a plenty ,yet much further north rain a plenty .

Some pretty chilly nights this summer but also some good days ,so at this point low pressure seams like becoming more of the order but no guarantee ,good growing weather though ,cheers gang .

[Summer Sun]

A short lived southerly a week today from ECM

 

 

You can see trouble is lurking out west and 24 / 48 hours later....

 

 

GFS at t192 and t216 also agrees on a deep low

 

[Dancerwithwings]

Very true.. Who said they were..? A long way to go yet in the Model 'World' before we have any consensus of what will unfold during August.

May i say them words again "A long way to go yet in the Model 'World" How right you are PM.

As we all know these charts are from 10 days prior to the 1st of July when parts of the UK had record temps for July.

Not much showing to say that in ten days time a plume was on it's way

 

So who's to say at this stage what's going to happen in August

 

Edited July 19, 2015 by Dancerwithwings

[Captain Shortwave]

A pretty average mobile westerly pattern is probably the best way to describe the output to be honest, some drier days under transient ridges before low pressure cross northern Scotland. A mix of warm and cooler days with the north ending up below normal (the amount dependent on the effect of the colder Atlantic waters) and the south being around average for the time of year. Rainfall looks quite showery though secondary lows could develop to bring widespread rainfall.

All in all it isn't too bad for the south, in the north it probably is a continuation of a rather poor summer with the continental heat not really making any presence felt.

[mushymanrob]

Just because theres no heatwave on offer doesnt mean its that bad.What i gleam from the current outputs is an improving picture as the week goes on. A lot of very pleasant summery weather on offer in any strong sunshine.

It could be worse, a lot worse, running slightly below average aint too bad guys.

The last week of july is a long way off and might not be as bad as some models predict. I certainly still dont see another 07, 08, 12, type regime currently.

[skifreak]

Not been looking in great detail but have been keeping a daily eye on the Aberdeen GFS ensembles and the continual trend for below average 850hpa temps is notable. There could be a few more days cool enough for summit snow in Highland Scotland this month. 

[knocker]

The anomalies at day ten tonight have the LP east of Greenland with trough over the UK and HP eastern Europe and Canada. Thus although the general flow is in the westerly quardrant with LP to the N and NE it will be intemmittently NW to N.. Remaining unsettled. But all is not lost. The ext period is still weakening the trough and the ECM in particular moves the eastern HP a tad west and brings the Azores more into play. The GEFS is not quite so progressive and still plays around with a weak LP area Iceland. But still on course for more of an Azores influence albeit with zonal flow and average temps.

http://www.tropicaltidbits.com/

Edited July 19, 2015 by knocker

[mushymanrob]

Think mushy the mjo just isn't playing ball for warmer and settled conditions. I believe that is our wild card model as from now. We need Tamara here badly to notify us of GWO and AAM.

 

i dont get the mjo.... i get the theory, but i dont find the mjo phase is a very good indicator as to what we are supposed to get. ill stick to the noaa anomaly charts as they seem to be most accurate for predicting the upper air pattern.

 

The anomalies at day ten tonight have the LP east of Greenland with trough over the UK and HP eastern Europe and Canada. Thus although the general flow is in the westerly quardrant with LP to the N and NE it will be intemmittently NW to N.. Remaining unsettled. But all is not lost. The ext period is still weakening the trough and the ECM in particular moves the eastern HP a tad west and brings the Azores more into play. The GEFS is not quite so progressive and still plays around with a weak LP area Iceland. But still on course for more of an Azores influence albeit with zonal flow and average temps.

http://www.tropicaltidbits.com/

 

indeed, a westerly flow out to two weeks ahead looks likely, whilst not great its probably the only way to return to possible high pressure dominance close to the uk. as i see it, theres no quick way back so a gradual upper air pattern shift is worth watching for if we desire a decent lasting settled spell. currently high pressure dominance is always in deep fi.

its fairly safe now to write off the rest of july in terms of heat. the anomaly charts predicted a trough to our northeast, high to our west, leaving the uk in a cool northerly sourced airmass. thats what we are going to get this week, very poor for those of us who desire heat, very good for those who dont, plenty of mainly dry weather too which i like and feeling pleasant in any sunny intervals. so not bad weather, just suppressed temps.

[Summer Sun]

Not a great deal of change overnight with a unsettled end to July looking quite likely its a case of how deep the low could be

 

Beyond day 10 high pressure could build for a time once the low has moved away

 

 

GEM has similar ideas with an unsettled spell next week with high pressure close by at months end as it does move closer we're left with a northerly flow for a time

 

 

GFS meanwhile keeps us unsettled a bit longer before high pressure builds for early August and temps in the south push up towards the high 20's

 

 

I should also point out we could see a ridge of high pressure on Sunday

 

Edited July 20, 2015 by Summer Sun

[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 MONDAY JULY 20TH 2015.

 

THE CURRENT GENERAL SITUATION. Relatively weak troughs of Low pressure will move NE across the UK today and tonight followed by a somewhat showery and fresher WSW flow.

 

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

 

MODELS-2 WEEK HEADLINE Still rather changeable with some dry and bright conditions mixed with occasional rain or showers. Temperatures largely near average but possibly warm at times in the SE at first and cool in the NW.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast keeps the flow blowing West to East across the South of the UK this week. Towards the start of next week it strengthens in situ for several days before the flow finally weakens and shifts North towards a more normal location and strength near Iceland at the end of the period.

 

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

 

GFS OPERATIONAL The GFS Operational Run today shows the UK gradually entering quite a slack pattern synoptically across the UK as this week progresses. With no one pressure feature having direct control the usual mix of plenty of dry weather spaced with scattered showers seems likely especially over Northern and Eastern areas in a light NW drift. Then next week sees a more direct attack from the Atlantic with rain and showers and cool conditions before right at the end of the period a pattern change evolves as High pressure builds across the UK with sunny and warm conditions for all then with the risk of a thundery shower in the SW.

 

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

 

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

 

THE GFS CONTROL The GFS Control Run is quite supportive of the operational run apart from the most desirable end part of the output where it has less extent to the build of High pressure at the end of the run, restricting it to Southern Britain while the North maintain Westerly breezes and occasional rain.

 

THE GFS CLUSTERS(14 Days) The GFS Clusters at 14 days show a roughly 60/40 split in preference of a High pressure ridge likely to lie across the UK from the Azores in 14 days time. The 40% show more disturbed weather for many with Low pressure in some shape or form to the North of the UK with Westerly winds and rain at times for all.

 

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 Low pressure to the North with a Westerly flow across the UK weakening as pressure becomes slack later in the week with a mix of sunshine and scattered showers. This looks maintained over the weekend as winds shift Northerly for a time before a weak High pressure dissolves most showers by Sunday away from the far East with a lot of dry and fine weather for all by then.

 

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

 

THE FAX CHARTS The Fax Charts this morning illustrate well the complexities of the rather slack atmosphere likely to develop across the UK later this week. Light winds, sunny spells and ccasional showers look likely as weak troughs meander about around the UK by then with temperatures never straying far from average overall.

 

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

 

GEM GEM today also shows relatively slack pressure later this week with some showers in a Westerly flow slowly veering towards the North. Then following a ridge next weekend the model shows quite a nasty area of Low pressure crossing the UK from the West early next week with wind and rain for all but at least it dangles a carrot at the end of it's run of High pressure building in strongly from off the Atlantic at the end of the period.

 

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

 

NAVGEM NAVGEM today shows a deeper Low pressure moving NE across the UK rather earlier than the other models. In fact as early as this coming weekend it looks like being breezy and cool with rain at times as that Low trundles NE across the UK.

 

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

 

ECM ECM this morning follows the main stream of the output with it's somewhat showery scenario through the working days of this week attached to Low pressure to the North and NE. Pressure builds at the weekend with fair weather for many for a time before next week turns cooler and breezy as Low pressure deepens as it moves into and out of Scotland towards Scandinavia at the start of next week with cool NW wind and showers following a band of rain SE to all areas. Pressure is then shown to build strongly across the North Atlantic at Day 10 perhaps indicative of an improvement at least in the West late in the week.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night shows Low pressure over Scandinavia with winds from between West and North across the UK with a typical pattern of sunshine and showers in average temperatures at best most likely by Day 10.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The main trend from the models maintain a slack Westerly flow across the UK before this veers to a stronger and cooler NW flow later.

 

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 95.5 pts followed by UKMO at 94.9 pts and GFS at 94.1 pts. At 5 days ECM is stll king at 83.9 pts followed by UKMO at 80.5 and GFS at 80.3 pts. Then at 8 Days ECM still leads at 53.7 pts over GFS's 48.2 pts. Finally at Day 10 ECM leads GFS at 34.6 pts to 29.9 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 Changes in weather patterning across the UK over the coming week or so are slow so one can only expect only day to day subtle changes in the weather through this coming week. Though details due to the slack nature of the pressure gradients across the UK later this week are going to be hard to pin down no particularly unpleasant weather looks likely with showers the order of most days for most folks. These should be well scattered but heavy and focused more towards the North and East through the afternoons but could occur almost anyhere as any weak troughs push through in the flow. This means of course all areas should see plenty of fine weather with sunshine too and in the SE it will stay warm for a few more days yet while the North and West in particular continue to see cooler conditions than elsewhere. We then have to wait until next weekend to see a shift towards generally dry weather as a weak High pressure area crosses the UK though high temperatures with this feature are unlikely especially by night when it could be quite cool for some Northern areas. The main change then looks to focus on Week 2 with a lot of cross model support for a more active Low pressure to move NE across the UK with wind and rain for all. As the Low then moves towards the NE and perhaps deepens further a cool NW, showery flow looks like feeding down across all areas. This signifies a pressure rise across the Atlantic by midweek of Week 2 which could spell a pattern shift towards High pressure across the UK towards the turn of the month providing the North or NW flow on the back of next weeks depression isn't stubborn enough to hold on which is unfortunately hinted at on ECM's day 10 chart. So in a nutshell still no guaranteed improvements in the models this morning but at least there is some interest shown in the extended output that a shift away from this North/South divide of late is possible as we enter August with all areas possibly moving towards fine, settled and hopefully summery temperatures to start the new month as High pressure built over the Atlantic next week edges over the UK from the West.

 

Next update from 09:00 Tuesday July 21st 2015

[Man With Beard]

Although the weather is generally forecast to become less summery everywhere, the long-range models continue to struggle this month. We've seen many runs trying to build the Azores High into to us with fairly poor verification, but on the other hand, many runs have tried to set up North-Westerlies and again have not really got anywhere. And indeed, it looks like we might have another failed North-Westerly for the weekend. Compare ECM three days ago (which seemed a favourable option at the time) and the latest ECM for next weekend:

 

http://www.meteociel.fr/modeles/ecmwf/archives/2015071712/ECM1-216.GIF?12

http://www.meteociel.fr/modeles/ecmwf/runs/2015072000/ECM1-144.GIF?20-12

 

I think the whole of July (leaving aside the first couple of days) can be summed up as a battle between ridging from the Azores and troughing to the NE (encouraged by the development of lows in the Atlantic encouraged by the jet) - and the result being a stalemate, although with tendencies for the trough to become more influential. This battle does not seem to be going anywhere in the next few days. Certainly, though, Tamara's call that NWlies would fail to set-up has been accurate so far.

 

I wonder, therefore, if any changes to our weather will actually be a little more subtle than some long-range charts suggest, and therefore all areas will continue to experience the odd warmer day, and the south will continue to escape any marked downturn. Just some thoughts.

[Summer Sun]

GFS 06z looks a bit erm different to the rest at t120

 

 

Compare with ECM and UKMO

 

 

3 models offering 3 different options just 5 days away

[Napplewh]

Where can i get a forecast for Majorca for August 30th 2015 are the CFS models useful?

[Yarmy]

Where can i get a forecast for Majorca for August 30th 2015 are the CFS models useful?

 

August the 30th in Majorca will be hot.