Model Output Discussion 12z 03/04/13

[Summer Sun]

Once the low pulls away pressure builds across Europe

GFS is becoming consistent now from mid month with high pressure dominating a good few runs now

Looks like a change for the better is finally on the cards after lots of failed attempts its now starting to come into a reliable time frame of t144 all that remains unclear is the track of the low tonight its fine for the east but the west looks wet especially Ireland ideally it will be further west still so we can all enjoy the warm settled weather

http://www.jp2webdes...o.uk/ds/gfs.htm

Edited April 8, 2013 by Gavin.

[Scorcher]

Another step in the right direction from GFS for those looking for warmer conditions- it has backtracked from previous runs and has the low further west for the weekend. Whatever happens it looks almost nailed on now that we will be experiencing warmer uppers by the weekend with southerly/south-westerly winds becoming established and continuing into next week, good to see the polar air disappearing from our shores, and not before time!

[Summer Sun]

Another step in the right direction as ECM places the low a bit further west and at a different angle compared to GFS

Much better from ECM at t144 as well with the high building in from the east sending the low up to Iceland (not the supermarket!) out the way

We've suffered enough cold over the past few months so this will be a most welcome change nice to see it in the reliable now as well

Edited April 8, 2013 by Gavin.

[mushymanrob]

the 12z gfs is a peach of a run, suggesting the remnants of the block being totally blown away (literally) by some very warm southerlies that moderate into next week but with slack winds in the south,( breezier in the north) would deliver some excellant springlike weather (no not sunny and warm all the way, changable but pleasant) before deep fi plume with heat..

ok the chances of that happening atm are remote, but something similar isnt unrealistic as the ecm (00z) certainly suggests something similar.

the ukmo agrees with the southerly blast on sunday, although not as breezy. so signes of a significant warm up in 6 days time is gathering pace, its not 'in the bag', but is becoming a stronger option. if its still there by thursday, across all three major models, then its fairly likely to happen. so whilst atm it might be gathering pace...its still along way off and theres still plenty of time for this to 'go wrong'.

[Methuselah]

Big warm up from the ecm,,,,,!! Big outlier

And no pesky haar-laden NE'erly, either...

[Summer Sun]

ECM continues to keep pressure high at t216

Thats both GFS and ECM which go for this now could be a prolonged dry, settled and mild spell coming after weeks of unseasonal cold nature will finally get back into gear

Edited April 8, 2013 by Gavin.

[Skeggy Winter Storm]

ECM continues to keep pressure high at t216

Thats both GFS and ECM which go for this now could be a prolonged dry, settled and mild spell coming after weeks of unseasonal cold nature will finally get back into gear

That would be very nice after the never ending Easterly all the trees are still bare round here can see few trees with buds about to spring into action

[Gibby]

Good evening folks. Here is the report from the 12z output of GFS, UKMO, GEM, NAVGEM and ECM for tonight Monday April 8th 2013.

All models shape the weather for the rest of the week and into the weekend in a similar fashion as a series of small depressions cross East across Southern Britain over the coming days with occasional rain more particularly in the South while the North stays dry and rather cold. later in the week rain spreads NE to more areas before a pattern change at the weekend when a deep Low develops in mid Atlantic and sending Southerly winds North across all areas with a substantial rise of temperatures to average or a little above later in the weekend.

GFS sends a trough NE across the UK late in the weekend and early next week followed by a broad SW flow with plenty of coud and occasional rain in the North and West but some increasingly long drier spells in the South and East as we move through next week and towards the end of the run.

The GFS Ensembles show good support for a change to warmer conditions from midweek on in the South and the weekend in the North as Low pressure to the West sends low pressure on a more regular track to the NW with the South and East becoming warmer and drier with time as High pressure builds to the South and East.

The Jet Stream is on it's way northwards over the coming week to be to the North or over the UK next week.

UKMO shows a fetch of mild Southerly winds this weekend with a lot of dry weather especially in the East as troughs edge slowly East into Western areas later in the weekend.

GEM tonight shows a feed of strong Southerly winds at the weekend too but has Low pressure closer into the West of the UK carrying gales and heavy rain North and East in milder air than recently.

NAVGEM has Low pressure spinning North and NE over the Atlantic with strong SW winds and rain for many for a time before this gradually becomes restricted to more Northern and Western areas towards the end of the output as temperatures steadily rise above average in the South later next week.

ECM is broadly similar with a wet and windy spell developing later next weekend in the north and West with only a little if any rain in the South and East. Through next week High pressure builds steadily from the South with warm air attached to it spreading North and East across England and Wales late next week with a fine and warm Spring spell developing with some warm sunshine with High pressure sitting over the South.

In Summary it appears that Spring is finally arriving for most late this weekend and next week. This week stays rather chilly with occasional rain at times, especially in the South before strong Southerly winds develop at the weekend with much warmer temperatures and eventually less windy and potentially warm conditions in Southern and Eastern areas as we move through next week. The Northwest in particular will stay more cloudy with occasional rain but at least also feeling the benefit of mild SW winds here too.

[KTtom]

Having run through the models tonight it might be worth bottling up every drop of rain you can on Thursday because its looking like a blip in a lengthy dry spell. Good support for temperatures to head towards the magic 70F just after mid month also.

Edited April 8, 2013 by KTtom

[Milhouse]

Having run through the models tonight it might be worth bottling up every drop of rain you can on Thursday because its looking like a blip in a lengthy dry spell. Good support for temperatures to head towards the magic 70F just after mid month also.

The bit of rain most areas gets this week should be the catalyst for a surge in spring growth with the arrival of much milder temperatures from Saturday onwards. ECM is a peach of a run and continues the very dry theme of this Spring so far. It would be a very strange Spring indeed if a switch was flicked mid April to a much milder pattern but still retaining the dry theme of Spring so far.

All of a sudden the jet stream is tracking SW-NE which is a very favourable direction for promoting warmth for the UK. The ECM ensemble mean lends good support for mild southwesterlies out to day 10 with pressure reasonably high over southern Britain. Less so for Scotland but all areas would be significantly warmer than at present.

[Alex]

Encouraging signs of some spring warmth on the models this evening; GFS ensembles confirm that we are likely to be heading into a period of above average temperatures.

London ensembles for the 18z: http://www.wetterzentrale.de/topkarten/fsavnmgeur.html

However there are large signs that we are about to enter a SE/NW split type.

Manchester ensembles indicate the slightly enhanced rainfall: http://www.wetterzentrale.de/topkarten/fsavnmgeur.html

My feelings are that the warmth will be felt during the latter stages of the weekend and beyond especially so, after such a large period of below average temperatures.

MJO is progged to enter a relatively strong phase 3 which indicates a trough setting up to the west of Ireland. Although not quite where I think we will see it, I think the broad idea of a trough to the west/northwest of us is correct and hence the reason for my initial SE/NW split option. I think the weakening of the MJO in the next few days could then see high pressure establish itself near to or over the UK within the next 10-14 days.

http://raleighwx.americanwx.com/MJO/AprilPhase3500mb.gif

My feelings on summer have already been shared in the summer 2013 thread, but I feel a NW/SE split pattern could return again during early summer especially with a weakish westerly based QBO and -PDO.

Catch my weather views on twitter - @alexbweather

Edited April 8, 2013 by Alex

[Guest pjl20101]

No change here on the CPC 8-14 day outlook as the +ve signal is still there to the SE corner, which is great and a vast improvement on our recent conditions:

http://www.cpc.ncep.noaa.gov/products/predictions/814day/814day.03.gif

Roll on the growing season I would say.

[skyblusam]

I follow this thread through the whole year. I love the cold and snow and the summer storms if i have any. But this year i cant wait for this winter to end and grab some gavin warmth. Ive had some great times along the way thanks to posters like gibby steve murr the eye in the sky nick susex and john holmes.As i have found when they post less winters ending. Then when storm season kicks in we have coast who posts up daily charts showing every chance anyone has . And to think i found this site by chance well its the best find ever. Ive found myself giving workmates a breif outlook on the weather from just reading this thread and been right about 7 times out of 10.And its all down to you wonderfull people on here .So this year im going to concentrate on understanding the models more

[mushymanrob]

I follow this thread through the whole year. I love the cold and snow and the summer storms if i have any. But this year i cant wait for this winter to end and grab some gavin warmth. Ive had some great times along the way thanks to posters like gibby steve murr the eye in the sky nick susex and john holmes.As i have found when they post less winters ending. Then when storm season kicks in we have coast who posts up daily charts showing every chance anyone has . And to think i found this site by chance well its the best find ever. Ive found myself giving workmates a breif outlook on the weather from just reading this thread and been right about 7 times out of 10.And its all down to you wonderfull people on here .So this year im going to concentrate on understanding the models more

not wishing to be controversial, but gibby and john post all year around from an unbiased pov...

well, its still there, a new day and all signes are that this pretty considerable warm up will happen this weekend, and afterwards return us to 'normal' or even above average into next week. the cold uppers are meandering northwards atm, and finally go by thursday.

[mountain shadow]

Aye, great news mushy, we could all do with some warmth and we have cross model agreement for that to occur over the weekend.

There will be rain in the North west but the grass could do with it.

[Polar Maritime]

This will certainly be a shock to the system, compared to what we have been used to over the past 5 months..

[IanR]

better late than never

[johnholmes]

thanks mushy, yes I do

comment this morning only brief as I have to go out so will do an in depth look at the 500's this evening.

all 3, been away 3 days, but they seem to have firmed up on what they were showing late last week, that is upper ridge from wsw of Iberia into eastern europe and marked trough aligned wsw-ene north of this, so an upper flow of air from a southerly region so making it milder at last. However, how settled needs a closer look.

To me from the last comment late last week I would suggest that they were 2-3 days premature in predicting milder air but the overall idea of the long lasting cold ending was correct.

more in depth this evening.

[picog]

This will certainly be a shock to the system, compared to what we have been used to over the past 5 months..

Will it be "sunny" or "cloudy' warmth? And will it be windy, taking the warm feel-good factor away?

[Summer Sun]

Will it be "sunny" or "cloudy' warmth? And will it be windy, taking the warm feel-good factor away?

Best chance of sunshine at this stage is East Anglia down into Kent

Looks like a cloudy muggy day for many away from that area

A good run from ECM this morning the main 3 seem to slowly be agreeing on sending the low west allowing pressure to build in from the east the exception to the settled weather looks to be the further west / north west you are

Sunday looks like we'll import some warm winds

As the week goes on the unsettled wet weather becomes more restricted to Scotland as we start to see the north south split developing

This results in the mildest weather for England, Wales and southern Ireland

So all in all changes for the better are on the way for many with this unseasonal cold now on its last legs finally

[chris55]

Looking forward to this warm up! Even though yesterday was still pretty cool you could definitely feel the change to a more maritime airmass, rather than the dry easterly air of late, that also brings a certain smell to the air. The weekend is going to feel lovely.

Hopefully the trough will stay to the west keeping any rainfall to a minimum,

[Polar Maritime]

Im sure detail will change.. but as it stands the Midlands South have the best chance of some long warm sunny periods, while the North could remain overcast and cloudy, but still pleasantly warm with overnight frost's under clear sky's. A front could then push in off the Atlantic by the following day.. April showers ?

Edited April 9, 2013 by Polar Maritime

[Gibby]

Hi folks. Here is the report on the 00z output from GFS, UKMO, GEM, MAVGEM and ECM for today Tuesday April 9th 2013.

All models continue to paint a more unsettled spell through the remainder of this week with Low pressure crossing Southern England at times delivering rain in the process which will extend further North at times into the cold air sitting there and delivering snow over the peaks with the far north seeing a few wintry showers at times in the cold East wind. By the weekend winds will turn Southerly everywhere bringing much milder air to all areas with rain into the West by Sunday as a deep Atlantic low drifts NE towards the far NW pumping High pressure up to the SE, lifting the Jet stream North and bringing a trough of Low pressure slowly East through Britain later in the weekend with some rain and strong breezes for all.

GFS then shows next week being a very blustery one with strong SW winds only dying down slowly through the week. Rain at times would gradually become more confined to Northern and Western areas only as the week progresses and probably die out altogether by the weekend as a ridge builds over the UK from the South. The milder air would persist over the UK through this week. Through the rest of FI further fine and warm weather looks likely though not without the occasional trough crossing East with some rain followed by bright and dry weather again to end the run.

The GFS Ensembles show good support for a strong warm up after this week with averages of around +5C in the South at the 850 level meaning temperatures should comfortably reach +15C or more in the South from next week on. Short term troughs could bring the occasional shower but beyond this week there is a fair amount of dry conditions shown under the influence of high pressure close to the SE.

The Jet Stream continues to be shown to lift away from it's Southern location to be blowing across the UK by this time next week.

UKMO for the start of next week shows a deep depression over the Atlantic to the NW of the British Isles with a fresh to strong SW flow over the UK weakening slowly from the South as a trough is carried Eastwards over the UK with some occasional rainfall. It will generally be much milder than of late.

GEM today shows a wet and windy spell to start next week with strong SW winds carrying troughs quickly East over the UK reinforced by another vigorous little feature around midweek bringing further wet and windy weather before things settle down in the South and East to end the week as winds fall lighter and skies brighten. Nevertheless, despite all the talk of rain it too shows much milder conditions for the UK as a whole next week.

NAVGEM shows a mild SW flow too next week with the wettest conditions from passing troughs reserved for the North and west while the South and East become progressively drier, brighter and warmer through the week.

ECM shows unsettled conditions for the NW next week with rain at times while High pressure lies closer to the SE from the start of the week with much less in the way of rain here. This pattern continues through the week with a NW/SE split likely with pleasantly warm and springlike conditions likely in the South and east while the north and West, particularly the far NW see more in the way of wind and rain from passing depressions out to the NW.

In Summary all models are singing from the same hymn sheet this morning with the UK finally seeing the back of the cold and grey conditions that the rest of this week holds and replacing it with a South or SW flow lifting temperatures markedly for all areas at the weekend. Next week settles into something of a NW/SE split with typical mild Atlantic based weather of wind and rain in the North and West with much better conditions in the South and East and as High pressure inches closer towards the South late in the week some pleasant warm sunshine could accompany the higher temperatures though the odd rogue trough could still bring a little rain here too. It does look as though at last with the Jet Stream ridging North over Europe next week it will finally dissolve the cold pool that has resided over NW Europe for so long and hopefully will not return until the Autumn.

[Scorcher]

Looking forward to this warm up! Even though yesterday was still pretty cool you could definitely feel the change to a more maritime airmass, rather than the dry easterly air of late, that also brings a certain smell to the air.

Yes I completely agree, there was a different feel yesterday despite the breeze picking up again, it certainly felt a lot more springlike- a taste of things to come for the weekend!

[danm]

Love the cold and snow in the winter, but now very much looking forward to warm Spring weather - especially after the bitterly cold March we've just had. Good to see the models agreeing on this for the weekend, at least across more southern and eastern areas. Looks to be a traditional NW/SE split coming up.