Model Output Discussion 12z 23/05/13

[Frosty.]

Probably David Cameron outlawed summer lol.

well he certainly outlawed spring

 

Despite the poor met office outlook, I still believe we are in for a warmer and more settled outlook, there are currently more than enough positives to take from the ensembles, especially the mean.

[Milhouse]

This is the closest the trough gets to the UK on the GEFS mean before pressure rises once again into FI.

 

[Barry12]

Hopefully the ECM 12Z will be better than the 00z, preferably like the ensemble mean and then we can open the champagne to the first good start to Summer in 7 years!

[Frosty.]

The Ukmo 12z at T+144 hours is a vast improvement on the 00z which showed unsettled weather into next weekend which the met office seemed to base the initial part of their 6-15 day update on, tonight's ukmo is now more in line or even better than the gfs 12z in the same timeframe with pleasantly warm and sunny conditions instead of rain followed by showers,  it's early days but this already bodes well for next weekend onwards.

[Summer Sun]

A good set of ensembles as well with low rainfall for the foreseeable and a trend upwards for the uppers

 

 

What a difference 12 months makes!

 

Edited May 26, 2013 by Gavin.

[Thundery wintry showers]

Tuesday is looking increasingly like an active day for weather with a rain belt moving up from the SE, possibly with some embedded thunder, and brighter weather with thundery showers over Wales and the West Country and much of Ireland.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130526/12/48/ukprec.png

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130526/12/54/ukstormrisk.png

The weather should turn drier on Wednesday but eastern areas are likely to be grey due to north-easterlies off the North Sea.  By Thursday, the winds are set to turn to more of a north to north-westerly direction and with a ridge of high pressure coming towards us from the west, so I think a fair amount of sunshine should come through in most areas with temperatures projected to be around 19-22C when accounting for the typical GFS underestimation.

 

To be honest I don't see much of a difference between UKMO and GFS at T+96 to T+144.  In both cases the high pressure ridges close enough to prevent the Atlantic rain belt on Friday from coming to much (probably just a belt of cloud and the odd spot of rain for most) and to prevent many showers from following in behind.  With a chilly polar maritime airmass source, next weekend is looking fairly cool but dry with sunny spells, bar a few well-scattered light showers down the eastern side of Scotland, and I think South Wales and SW England are likely to be sunniest and warmest overall.  After that, chances are that the ridge of high pressure will head over to the British Isles promoting warmer conditions with further sunshine, but it is unclear how long it will last for, as the outputs indicate a fair amount of uncertainty over where the high ends up after its trip over the top of Britain.

Edited May 26, 2013 by Thundery wintry showers

[Frosty.]

A very satisfactory GEFS 12z mean from T+168 onwards with the azores anticyclone in control, this is very similar to the stunning Ecm 00z ensemble mean this morning with an increasingly warm and settled outlook, let's hope the ecm 12z ens mean keeps the momentum going.

Edited May 26, 2013 by Frosty039

[Summer Sun]

Well ECM isn't bringing the high in as quickly as UKMO at t144

 

 

Where as UKMO has this

 

 

ECM is going in the right direction just not as quickly as UKMO it won't be until mid week before we see good agreement on things for the weekend but the signs are certainly there now

 

[Polar Maritime]

Summer is here!! 

 

Another 5 days yet 

[Summer Sun]

And there we have it ECM is there just a day behind UKMO

 

 

And with the low getting forced into Greenland that's a positive sign. Another positive is that high pressure is having a say in things this year unlike 12 months ago a decent start to summer is on the cards

Edited May 26, 2013 by Gavin.

[Barry12]

NAVGEM also on board the high pressure train, although much slower:

 

[Frosty.]

WOW tonight's Ecm 12z op run is a huge upgrade on the 00z with the azores high building in at a much better angle to bring a warm and summery outlook, this run is far more reflective of the ecm 00z ensemble mean this morning and bodes very well for the 12z mean tonight...we are moving in the right direction guys...BANK .

Edited May 26, 2013 by Frosty039

[Barry12]

Also the Moscow Europe model agrees!

 

[Barry12]

BOM:

 

[Barry12]

GEM - Struggling to find a model not on the high pressure train.

 

Edited May 26, 2013 by Barry95

[Summer Sun]

ECM 12z ends potentially iffy for the north with the low across Iceland just extending southwards a bit but all in all a superb run not to be sniffed at

 

[Frosty.]

BOM:

 

 

I like the colours on netweather better

Edited May 26, 2013 by Frosty039

[Milhouse]

Lots of variation there with the positioning of the high so not all areas will see warmth but the general trend is promising for a good start to summer. Also note low pressure firmly over Greenland at t240 on the ECM.

[Gibby]

Hi everyone. Here is the evening review of the midday outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Sunday May 26th 2013.

All models show the ridge of high pressure crossing the UK collapsing away tomorrow as Low pressure deepening to the NW of Britain pushes a trough East across the UK tonight and tomorrow reaching SE England by evening. Through the middle of the week a very showery spell seems likely with heavy and thundery showers across all areas. Later in the week pressure is shown to build into the UK from the Atlantic with showers becoming more and more restricted to the far SE by the end of Friday with plenty of dry and increasingly sunny conditions developing for the majority of Britain before the weekend.

GFS then shows the weekend with pressure continuing to build over the UK with dry and bright conditions for many with temperatures close to average. Through the following week more unsettled conditions edge back into many parts of the UK from the NW for a time before pressure rebuilds by the end of the week and this time some real summer warmth could become established over the UK along with good sunny spells.

The GFS Ensembles show the strongest support yet for a strong rise in uppers later this coming week and more especially in week 2. There seems every chance that the unsettled and cool weather of this week may be replaced by drier and warmer conditions with some summery sunshine developing with fewer of those pesky showers.

The Jet Stream shows the flow still flowing SE just to the West of the UK joining the Southern arm over Southern Europe. Later this coming week the flow weakens and eventually peters out altogether around the UK along with the Eastern and Central parts of the Atlantic.

UKMO tonight shows a Northerly flow over the UK and the end of the working week and start of the weekend. A strong ridge of High pressure is building towards NW Britain from the SW with fine and dry conditions here with sunny spells. In the East and SE a cooling Northerly flow could still bring the odd light shower but even here plenty of dry weather will be enjoyed. Temperatures will be close to average for most.

GEM tonight shows High pressure ridging towards NW Britain at the end of the week moving further on to show a High centre developing close to the NW while Southern and Eastern areas become influenced by a somewhat cooler NE wind with variable cloud cover and the odd shower.

NAVGEM too shows the same theme with the Highest pressure close to NW Britain from next weekend with fine weather for most but no heatwave yet as winds stay NE down over the East and SE.

ECM tonight is desperately trying to join the party and eventually does so though patience is required as it keeps a stronger Northerly influence down over the UK all the way to Sunday with some showers to boot too which could be heavy in the afternoons and more especially in the South. Late in the run High pressure builds NE deeper into the UK mostly cutting off the North feed from all but the far SE early next week. Plenty of dry and settled weather would be experienced and it may become comfortably warm for many in the prolonged sunshine. The 240hr chart does indicate some concern though as a void is developing over the UK from the receding ridge South-westwards which could open the door for another surge of low pressure energy from the NW in the following days.

In Summary there is still a good and in some instances a growing trend for dry and settled conditions to develop for 90% of the UK beyond next weekend as High pressure builds into the UK from the SW. There are some 'if's' and 'but's' still to be nullified before confidence is complete but with each passing output the chances of it verifying are increasing. The output does not reflect the mid term outlooks delivered from the Met earlier today but I'm sure if such improvements are still held on the midnight runs I'm sure there will be better news from them tomorrow and most certainly on Tuesday. Leaving this weeks rainfall aside and the slight worry of the ECM 240hr chart there is a good chance that sustained dry weather could last quite a while should High pressure build as shown tonight.

[legritter]

Certainly its steady as she goes .a mixed bag to start the week then a promise of high pressure settling in .i think most folk will be glad if we can get some nice warm weather and with long daylight hours we can all get some outside living in .its a hard one to call past next weekend but atleast we are looking at good possibilitys .but looking at all modells and Data i would be inclined to keep an eye on energy to our north west as this could be our enemy for some while ,but enjoy anything summerlike we certainly need some .

[Frosty.]

Countryfile forecast was a mixed bag but that's what we expected because all the good stuff is from around T+168 hours onwards, tomorrow's rain will be mostly on the western side of the uk and it will fragment as it eventually staggers further east tomorrow evening and night, tuesday and wednesday look unsettled with some rain and showers but then somewhat drier, brighter and potentially warmer later in the week as weak atlantic ridging spreads east, some rain on friday but up to 19c 66f if the sun breaks through, then improving next weekend, especially from sunday onwards.

[Summer Sun]

The ECM ensemble run keeps up the growing trend for pressure to build later this week

 

[Thundery wintry showers]

One trend that I'm consistently seeing on tonight's runs is that there is less certainty over the persistence of the high pressure (the GEFS and ECMWF ensembles had pressure around 1025mb earlier, now it is generally nearer 1020mb) but on the other hand the high is generally centred further south and east.  This reduces the likelihood of eastern areas being affected by cool cloudy conditions delivered by NE winds off the anomalously cool North Sea, although at the same time it makes western and north-western Britain potentially more prone to influences from Atlantic weather systems.

 

The ECMWF is at odds with UKMO/GFS for next weekend- that stiff northerly flow would probably bring a rather cool feel with some scattered showers, unlike the UKMO/GFS outputs which tend more towards dry and sunny with chilly nights.  However the ECMWF ensemble mean is closer to the GFS/UKMO outputs than the ECMWF operational run, suggesting that the operational was probably at or near the cold and windy end of the range of possibilities.

[mushymanrob]

hmmph.... this mornings op runs appear to be less progressive regarding the much vaunted june settling down. the ukmo is the best, but the gfs and ecm appear to be backing off somewhat and the gfs suggests that after this weeks trough, the pressure build MIGHT only be another breif ridge before more atlantic weather pushes in.

 

the anomaly charts though do appear to be firming up on some sort of mid/upper latitude high, with warm dry easterlies...

[ANYWEATHER]

Gfs is mocking its previous runs even in FI out as far as t+168 as to pressure building across the Uk, this mornings run will be disappointing im afraid for anyone looking for warm ,settled conditions....Lets see what the Ecm shows?