Model Output Discussion 12z 01/06/13

[summer blizzard]

Summer over?

 

[William of Walworth]

Summer over?

 

I can confidently state that such a question is likely to be nonsense! (I presume you jest?)

[mushymanrob]

I can confidently state that such a question is likely to be nonsense! (I presume you jest?)

 

depends upon whether that chart varifies or not.... if it did then its highly likely (given recent summers, recent trends) that at least a large chunk of summer may well be written off. fortunately its well into fi, but id be concerned if it was within t144.

[Scorcher]

 

I can't see anything, including tonight's ECM (pictured), to suggest that continental air will survive beyond 7 days from now. GFS for the first time in days is correcting the low eastwards. Breaks my heart.

A spell like this ten years ago, we'd have seen high twenties, surely? As opposed to twenty.

 

 

 

Slightly dramatic post, this morning run's have shown that low further west again- GFS has backed down this morning as it has been the most progressive of the main models over the last few days. No sign of anything particularly hot but also no sign of nothing like we had last summer with those deep southerly tracking lows. We haven't really had any particularly warm uppers yet to support the kind of temperatures you mention.

[Barry12]

What I find weird is we've managed high twentys in April, yet we seem to be struggling to get to mid twentys in June. I'm sure this setup in July and August would manage high twentys though.

[Frosty.]

The generally fine and warm spell is set to continue well into next week but the overall model consensus is that the fine spell will be eroded from the west as we progress through next week and that the far northeast will probably hold on to the driest weather for longest but there still remains a lot of uncertainty as to the timing and extent of the breakdown. The gfs 00z shows largely dry, fine and warm weather persisting for most of next week with the rain bearing fronts held well back to the west across ireland with pressure remaining fairly high for a long time across central and eastern areas, hardly any shower activity ahead of the fronts either, the Ecm 00z shows high pressure only slowly giving way but there is an increasing threat of heavy, thundery showers but we remain in a warm and muggy stagnant airmass next week. In the next six days or so, high pressure will be in charge with lots of sunshine with just a small risk of a sharp shower here and there, mainly for scotland and warm temperatures of around 20-22c but some parts of the uk will be closer to 23-25c at times. 

 

Tomorrow looks sunnier and warmer than today, some areas could reach 24c 75f tomorrow and that sets the tone for friday, the weekend and early next week.

Edited June 5, 2013 by Frosty039

[Gibby]

Good morning folks. Here is the report from the midnight outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Wednesday June 5th 2013.All models show High pressure holding control of the UK weather for some time to come. Between now and the end of the weekend the High will remain to the North of the UK with a slack ridge of high pressure stretching down over the UK holding off Atlantic low pressure to the West and thundery Low pressure to the South. Most places spare the odd shower will be dry and fine between now and the start of next week with temperatures above average and some good sunny spells for many away from cooler windward coasts.GFS then keeps the status quo going into the middle of the week with a lot of fine and dry weather. A trough will be feeding in from the West with some showery outbreaks of rain spreading in from the West on Thursday with showers breaking out more widely over England and Wales by next weekend. FI today shows a change to cooler conditions from the NW in Week 2 as a ridge collapses away SE and Atlantic fronts move East and South across the UK bringing cool and unsettled conditions to all areas by the end of the run.The GFS Ensembles today show warmer than average conditions continuing until around the 20th and 11th when cooler conditions take control from then until the expiry of the run. Rainfall amounts remain low though throughout the period of cooler uppers with no sign of any widespread heavy rainfall with most of it progged as showers.The Jet Stream currently blowing well to the NW of the UK weakens over the next 4-5 days before realigning across the Atlantic to Southern Europe as we move through next week.UKMO shows a period of slack winds under slack pressure gradients over the UK at the weekend with the largely fine and settled weather of then giving way to more unsettled conditions next week as low pressure is shown to edge a trough in from the SW on Monday with attendant showery rain in tow for most Southern and Western areas on Monday.GEM today keeps a ridge stretching down from the North over the first half of next week with any isolated showers reserved for the extreme South while most other areas stay completely dry, bright and reasonably warm in the sunshine. Late in the week Low pressure makes it's move towards the SW at the same time as low pressure passes SE to the NE with rain or showers possible at opposite ends of the UK while central regions remain in nomansland and possibly remain largely dry.NAVGEM holds a ridge over the UK from the SW through the weekend sliding slowly SE while taking the first half of next week to clear the South Coast maintaining dry, bright and reasonably warm conditions going. From midweek Atlantic Low pressure does make inroads into the UK with rain bearing troughs moving in with rain and strengthening SW winds making it a much more unsettled and cooler end to the week.ECM today holds a ridge of high pressure over the UK early next week holding off any progression towards more unsettled conditions until the middle of next week with dry, bright and reasonably warm conditions continuing under very light winds. From midweek though a change does take place with Low pressure, wind and rain moving into the UK from off the Atlantic to give a wet end to the week, especially in the South. As a result it would become much cooler.In Summary there is still some differences of opinion between the models as we go through next week. Between now and then the weather continues to be shown set fair with pleasantly warm if not record breaking hot conditions continuing with sunny spells and, under slack pressure conditions the odd heavy shower could break out over the hills at times. Through next week Low pressure does make inroads into the UK with time but it's progress is slow and erratic between the outputs with the South and West at greatest risk of seeing a change in conditions first with changes further East and North much harder to call.

[johnholmes]

Not too much consistency fom the anomaly charts so they add nothing to the vagaries of the synoptic ouput really other than a general guide that upper ridging will be in place between nw and ne of the uk with upper troughing over or close by the country.

[Gael_Force]

What I find weird is we've managed high twentys in April, yet we seem to be struggling to get to mid twentys in June. I'm sure this setup in July and August would manage high twentys though.

 

On these occasions the air mass has been from a direct southerly flow, this time the warmth has been mixed out in the arctic and further modified over the very cold seas. Irrespective of temperature, it is fantastic to have warm sunshine instead of cold, dreich days.

[Summer Sun]

Once again the ensembles show its a case of where you live for rainfall this morning

 

Those further north look like staying driest longest with the Aberdeen ensemble showing little rainfall until at least the 15th now quite possibly even later

 

 

Those Manchester south see rain from later this weekend or early next week

 

 

Dublin starts to see a slight increase on the 11th but really its late next week before the risk of rain increases more

 

[Thundery wintry showers]

The Aberdeen area indeed looks favoured to be one of the driest parts of the UK over the coming week, but there's also a fair chance of it ranking among the coolest and cloudiest, as "haar" is likely to be a persistent issue with the winds often coming in off the North Sea.  For central and western parts of Scotland it's a very different story- here sunshine and modest warmth are likely to persist for quite some time.  It's a similar scenario for most of England and Wales bar the far south, and south of the Scottish border even eastern coastal areas will probably have more sunshine than low cloud, though cooler than in central and western areas.

 

Today is proving grey and cool over many parts of the country but the satellite images support the notion of it being a one-off away from eastern coastal areas, since skies are relatively clear in the northern and eastern North Sea at the moment and what cloud remains is weaker and more likely to burn off as it heads inland.

 

For the long-term there is growing agreement on an Atlantic trough slowly heading eastwards but uncertainty on the detail.  The current model outputs are hinting at a slack and probably bright and showery type of setup evolving, but there is the issue that if the jet stream then intensifies (which normally happens at some point between early June and early July) then unless the jet moves northwards in the meantime we can expect a dull wet spell at some point later on in the month.

Edited June 5, 2013 by Thundery wintry showers

[The PIT]

Is it me or are seeing hints of the jet stream moving south and firing up again? If it is hopefully it won't get stuck in the fired up mode in that position, That is what's killed the last few summers.

[snowking]

Some subtle differences in this mornings Ensemble means, but largely a similar picture as we move through next week, with lowering heights and lowering pressure likely to turn things rather more unsettled, with conditions that look conducive of a sunshine and showers type setup:

 

 

Perhaps the risk much later on of low pressure rolling in off the Atlantic:

 

 

Though as you can see, still differences in the overall suggestion towards day 10 even from the ensemble means

 

So a slight downhill turn likely next week

 

SK

[Harry]

 

I can't see anything, including tonight's ECM (pictured), to suggest that continental air will survive beyond 7 days from now. GFS for the first time in days is correcting the low eastwards. Breaks my heart.

A spell like this ten years ago, we'd have seen high twenties, surely? As opposed to twenty.

 

 

 

I wouldn't agree with this to be honest....in order for our temperatures to launch upwards from mid-high twenties and beyond we need the primary jet stream to be north of us so we are under the influence of the warm sub-tropical airmass. This however isn't the case at the moment as the primary jet is some way south...while the charts suggest the jet is toppling over the ridge way north of Scotland at present, this appears to be somewhat misleading (a split in the rossby waves appears to be occurring) as is shown when the jet reinvigorates in the coming days and shows its true track way to our South over the Iberian region. We are therefore under a relatively mild airmass at the moment but without the subtropical air you would associate with in this setup...it's quite bizarre to say the least...we are in a quandry where we are not strictly speaking under a polar airmass but neither a warm sub-tropical one - hence why (along with the cold SSTs) we are struggling with the temperatures IMO.

Edited June 5, 2013 by Harry

[Frosty.]

The Ecm 00z ensemble mean shows a weak ridge extending down from the north during the early part of next week, gradually the ridge pulls north and the uk is then within a slack, warm and humid zone with pressure slowly leaking away and after a dry and sunny start to next week, the threat of showers increases, atlantic low pressure edges slowly eastwards towards the uk but remains out to the west, the weather becomes more and more showery, probably some heavy and thundery showers but still with some sunshine and feeling warm and humid with temperatures continuing to at least reach the low 70's F.

[johnholmes]

Take a look at the Net Wx dewpoint and isobar charts and run them through to see where the airmass is originating and how the model is currently predicting things to turn out.

The air mass over the past few days is Pm or rPM that is polar origin so to expect temperatures much higher than some places have experienced is expecting too much. If the high sat over the UK for several days as a cloud free high with no breeze other than heat induced sea breezes numbers in the high 20's would occur.

[summer blizzard]

I can confidently state that such a question is likely to be nonsense! (I presume you jest?)

 

Yes, it was a joke although i don't mind cool summers anyway (hate humidity and high minima more than anything else).

 

Worth noting that the GEM picks up that low...

 

[Milhouse]

The GFS 6z follows on from the 0z in prolonging the fine and warm spell well on into next week and, following a brief hiccup, into weekend of the 15th and 16th.

 

[Frosty.]

The Gfs 06z operational run shows our warm and generally settled spell persisting into the beginning of next week but then slowly becoming more unsettled from the west with some heavy, showery and potentially thundery rain pushing north & east, however, it remains warm, locally very warm and rather humid until later next week with temps well into the 70's F, it gradually becomes cooler across the north and west but southeastern britain continues on the warm side for the whole of next week, eventually the showery humid spell is replaced by a more mobile atlantic pattern with low pressure to the northwest of scotland but the azores anticyclone ridging across the south with the best of the warm and drier conditions down there, a northwest-southeast split develops through the second half of FI with the most unsettled, coolest and windiest weather across northwestern uk but occasionally this unsettled weather pushes further south & east, very often it seems like the gfs reverts to default atlantic mode in the low res part of the run.

 

This recent satellite image shows more cloud across the uk today but most of this should burn back to the east coast this afternoon, tomorrow will be sunnier and warmer than today.

Edited June 5, 2013 by Frosty039

[AWD]

Looking at the London EC ens shows a cooler (although still relatively warm) start to the new working week next week after a warm and mostly sunny weekend to come;

Temperatures average or very slightly below as next week progresses, with a slow increase in rainfall projections;

Again though, there is no serious amounts of rainfall shown there, suggestive that what does fall from the sky is more likely to be the showery/convective type rather than the frontal type.

[Frosty.]

There is a heck of a lot of uncertainty in today's met office update regarding next week, timing and extent of breakdown are very unclear with some warm fine weather to be had but also cool unsettled weather with rain and showers, pretty much the same uncertainty from the op runs today with various scenarios ranging from fine and warm from the gfs 00z to warm, humid and showery from the ecm 00z, perhaps the gfs 06z was somewhere inbetween with an unsettled trend but remaining on the warm side for most of next week, especially further south & east.

Edited June 5, 2013 by Frosty039

[Barry12]

MONDAY

 

 

Still fairly warm

 

 

TUESDAY

 

 

Edited June 5, 2013 by Barry95

[Summer Sun]

UKMO is now showing a deep low moving in from the west early next week with its centre located NW of Scotland

 

 

And GFS's take on it for the same time

 

 

Remains warm especially in any sunny spells

 

 

Temperatures widely in the high teens or low twenties away from the coastal strip

 

 

Remains mainly dry for Monday just the odd shower about in the north west and parts of Scotland

 

 

Tuesday remains dry in the east wet in the west

 

 

 

 

[Frosty.]

This evening's ukmo 12z shows the fine and increasingly warm weather persisting until early next week, the weekend ahead looks very warm and settled with benign conditions as high pressure sits to the east with the atlantic low anchored further west but early next week that depression get's a move on and accelarates further east rather faster than the 00z but it only really makes inroads into northwest britain, the south & east of the uk look like remaining fine and warm next monday and tuesday but rain spreads into the western side of the uk, the western side of the uk could potentially have a lot of rain if fronts stall and wave features run northeast, that high to the southeast of the uk could keep the southeast of the uk warm and dry for most of next week.

[SnowObsessor90]

The GFS seems to have stalled, I wonder why that is.