Model Output Discussion 12z 01/06/13

[Buzzit]

Following on from Mushy's comment related to the Jetstream - the weekend seems to be the point in the balance at the moment. Personally i do not want to see the jet reaching more southerly in this manner but if there is so much slack pressure about it does have every chance of doing so. Ensembles over the next couple of days will be interesting

 

6pm Sat  6z 12z

 

 

9pm Sun 6z                                   12z  

[johnholmes]

The anomaly charts, the most reliable indicator, note I said indicator, at the 6-15 day range does suggest that unsettled rather than settled and not warm is the 6-15 day form horse.

[Summer Sun]

Looking at the 12z ensembles and uppers should be around average at worst and the further north you are the lower the rainfall is shown to be (as indicated by the Aberdeen ensemble)

 

Edited June 3, 2013 by Summer Sun

[AWD]

The anomaly charts, the most reliable indicator, note I said indicator, at the 6-15 day range does suggest that unsettled rather than settled and not warm is the 6-15 day form horse.

Just seen the updated versions and I do agree they have shifted towards a more unsettled outlook in week 2 now. Slight differences but the Atlantic trough and European trough look like influencing our weather as heights towards our north receed;Is the red circled line the forecast Jet Stream flow? Edited June 3, 2013 by AWD

[phil nw.]

It looks like the fine and dry weather over much of the UK will hold this week with daytime temps.easing up.This thanks to the Azores high throwing a ridge this way.

http://www.wetterzentrale.de/pics/Rukm1201.gif

 

That Iberian low will give mainland Europe rain and showers through the next few days but any breakdown for us seems over a week away with the approach of the next Atlantic trough.In fact it' s odds on for another decent weekend at the moment.

 

Too early to say how much of a change we will see but ens outputs do favour rain or showers moving in from the west early next week but in the meantime we have lot's of lovely early Summer sun to enjoy.

[Summer Sun]

Another settled warm weekend remains on track

 

 

Edited June 3, 2013 by Summer Sun

[damianslaw]

Reliable timeframe at long last a dry settled fine warm spell ahead with plenty of sunshine thanks to the azores high nudging in a ridge which will settle over the country enabling 'homegrown' warmth to develop as we move through the week. Its an outlook many have been craving for over the last few weeks and just the tonic it has to be said given the very chilly spring we have endured. Perfect time of year as well for such weather with the long days and fresh early season growth abounding - great stuff..

 

Longer term signs that this may be a temporary fine spell as the atlantic trough once again noses itself into place over the country as the azores high puts a weak fight - the theme of the last 6 summers..

 

Enjoy the week ahead if you like fine dry warm sunny weather - I wouldn't bank on equivalent weeks occuring during the rest of the summer, a 7 day fine dry sunny and warm spell isn't easy to come by in our british summers. June on average is much drier and more settled than July and August remember, just the last few years have seen wet Junes as well.

[Frosty.]

Ecm 12z op run showing the sunny and warm weather persisting through the weekend, looks as good as the ukmo 12z with very warm and mostly sunny weather across most of the uk, only the far north/northeast missing out on the sun and warmth this week, inland and especially across the south & southeast of england are set to become very warm and locally hot with temps of 25-26c, maybe a few lucky locations will break through the 80f barrier on friday or the weekend, the fine and very warm spell persists into next week.

Edited June 3, 2013 by Frosty039

[AWD]

That Iberian low will give mainland Europe rain and showers through the next few days but any breakdown for us seems over a week away with the approach of the next Atlantic trough.In fact it' s odds on for another decent weekend at the moment.

I would agree that the favourable outcome is for another settled and mostly dry weekend, with good amounts of data to support that.However it's worth noting that the GFS Op brings quite a widespread risk of showers on Saturday over England & Wales;And with some instability and energy brewing Saturday afternoon, some of these showers could turn into thunderstorms;As you can see from above, plenty of convective energy over France too that wouldn't take much to influence a greater portion of Southern England either. Not saying it will happen, the GFS is very fickle at this timescale, just saying it's something that has popped up lately, not just on tonight's GFS Op either, but on a couple of runs over the last 24 hours too, as been discussed in the Convective thread.To a lesser extent, the EC Op also flirting with the idea of the above scenario;This is the sort of thing the FAX charts are best for, as these might show a trough embedded in the flow over Saturday if of course the Met Office think this is plausible. Edited June 3, 2013 by AWD

[Summer Sun]

Pressure becomes slightly lower as we start the new working week but it remains warm

 

[049balt]

Reliable timeframe at long last a dry settled fine warm spell ahead with plenty of sunshine thanks to the azores high nudging in a ridge which will settle over the country enabling 'homegrown' warmth to develop as we move through the week. Its an outlook many have been craving for over the last few weeks and just the tonic it has to be said given the very chilly spring we have endured. Perfect time of year as well for such weather with the long days and fresh early season growth abounding - great stuff..

 

Longer term signs that this may be a temporary fine spell as the atlantic trough once again noses itself into place over the country as the azores high puts a weak fight - the theme of the last 6 summers..

 

Enjoy the week ahead if you like fine dry warm sunny weather - I wouldn't bank on equivalent weeks occuring during the rest of the summer, a 7 day fine dry sunny and warm spell isn't easy to come by in our british summers. June on average is much drier and more settled than July and August remember, just the last few years have seen wet Junes as well.

You are taking a very depressing view on the prospects for the Summer a head, I do hope we will see more that just one dry spell.

[Summer Sun]

The Atlantic is there ready and waiting to move in high pressure re-establishes over Greenland it does remain warm though

 

Edited June 3, 2013 by Summer Sun

[Milhouse]

 

Enjoy the week ahead if you like fine dry warm sunny weather - I wouldn't bank on equivalent weeks occuring during the rest of the summer, a 7 day fine dry sunny and warm spell isn't easy to come by in our british summers. June on average is much drier and more settled than July and August remember, just the last few years have seen wet Junes as well.

 

Rather negative if i may say so. It appears the recent wet summers have skewed some peoples opinions on what we can expect summer to be like in the UK. Another warm and settled week may occur again, who knows, but if the breakdown does occur when the GFS says it will then we will still have 12 weeks left of summer. Loads of time for another settled spell.

[Frosty.]

The Ecm 12z is playing out like the met office update with the threat of heavy showers with thunder breaking out early next week as pressure leaks away but it would be warm and humid, similar by midweek with the atlantic low stalling out to the west, on the gfs 12z, the low out west was a shallower feature which merged with a trough to the south of the uk, pressure remains rather higher to the north of the uk, as per the gfs 12z. Eventually low pressure takes control later next week with a cool down but it's a slow process.

Edited June 3, 2013 by Frosty039

[Milhouse]

The Atlantic is there ready and waiting to move in high pressure re-establishes over Greenland it does remain warm though

 

 

 

The way the low is spiralling round in the Atlantic shows its main energy isnt going eastwards, thanks to all the high pressure to the north of the UK.

[Milhouse]

It eventually makes it over the UK though

 

[Summer Sun]

t240 sees the low getting in still warm though

 

 

It seems inevitable that we'll see a break down during next week however nothing is nailed on yet for the exact timing as its simply too far out to be certain.

Edited June 3, 2013 by Summer Sun

[Frosty.]

t240 sees the low getting in still warm though

 

 

It seems inevitable that we'll see a break down during next week however nothing is nailed on yet for the exact timing as its simply too far out to be certain.

Yes at least the breakdown looks slow compared to what the Gfs 6z showed, the warm weather looks like lasting into next week but with falling pressure and increasing humidity, that's a perfect recipe for heavy thundery showers but still with some warm sunshine.

Edited June 3, 2013 by Frosty039

[johnholmes]

Just seen the updated versions and I do agree they have shifted towards a more unsettled outlook in week 2 now. Slight differences but the Atlantic trough and European trough look like influencing our weather as heights towards our north receed;

image.jpg

Is the red circled line the forecast Jet Stream flow?

No

The lines showing the predicted 500mb flow are largely black. But they show colours that indicate what kind of heights are expected so from 516, 528 (the famed blue line of snow prediction when used in thickness charts not actual 500mb heights) 546(green) and the 564 red line. This tends to indicate where the major warmth is in the northern hemisphere not the jet stream. The closer the contour lines are then the stronger the flow at that height so some indication, no more, that where the 500mb maximum wind is can quite often be an indicator of where the strongest winds at 300mb can occur, the jet stream to give it its common name. Technically the ICAO and WMO, flight and meteorological world guidance bodies set 80 knots or more as a 'jet stream' Obviously it can be a lot more than that at times.

sorry such a long post.

[summer blizzard]

What an odd run from the GFS12z, the low gets through but we never lose the warm airmass and end up with cloudy, humid (possibly thundery), wet weather. 

 

JMA however keeps plodding along...

 

[Alex]

I think it's fair to say that the background signals favour a trough probably just to our west in the 7-10 day timescale.

We have a rather negative angular momentum level and with MJO moving into phase 3, this favours trough action close to the UK.

Also to note is that the last stratopsheric warming hasn't receded yet so northern blocking could well be favoured.

As others have said - enjoy it while it lasts!

[Gibby]

Good evening. Here is the report on the midday output from GFS, UKMO, GEM and ECM for today Monday June 3rd 2013.The broad scale synoptic pattern remains controlled by High pressure transferring from the UK slowly North through the week. The weather will be largely fine and dry with long sunny spells and warm conditions with a light easterly wind through the rest of the week. A few well scattered showers could occur here and there later in the week, most likely in the North.GFS then shows more unsettled conditions later in the weekend and into next week as Low pressure moves in from off the Atlantic across Southern Britain with some heavy rain developing across these areas into the new week. The North will largely miss a lot of this rainfall though more extensive unsettled conditions gradually develop for all later in the week with rather cool conditions likely by the end of the run.The GFS Ensembles show the warmer spell losing it's grip beyond this week with a return to average conditions with rain at times from the end of the weekend and start to next week.The Jet Stream shows the flow way to the NW at the moment, such as it is with this weakening over the coming days and realigning across the Atlantic towards France and Spain by next week.UKMO has High pressure centred over the North Sea next Sunday with lower pressure lying towards the South and SW of the UK. There is a considerable chance of thundery showers edging into South and the SW of England and Wales late next Sunday and beyond.GEM tonight shows slow changes from next weekend as High pressure slowly loses it's grip in response to troughs of Low pressure advancing NNE across the South early next week with a West/East split developing towards the end of the run with the highest chance of rain likely in the West.NAVGEM shows Low pressure easing it's way East into the UK early next week with the chances of rain increasing steadily with time.ECM finally also shows falling pressure from the end of the weekend and into next week. Changes in weather are slow though with some places staying dry until midweek when the scattered thundery showers give way to something more Atlantic based late in the run with more extensive and heavy rainfall in cooler and breezier conditions.In Summary tonight the weather remains set fair between now and the weekend with the vast majority of the UK enjoying warm and settled conditions with sunny spells and the odd sharp shower, most likely in the North over the next few days and the South at the weekend. Next week looks like changes are more likely as Low pressure erodes the high pressure gradually away North with an increasing threat of showers or even longer spells of rain moving up from the south or SW as we move through next week as well as temperatures returning to average levels or a little below in the rain. having said all of that there is still a lot of uncertainty shown in specifics next week so expect further changes in the model output's in the days ahead.

[Frosty.]

The Gem 12z has also served up some yummy charts for the weekend with high pressure in total control, so the coming days including the weekend look mostly sunny and becoming warmer each day with the weekend being the peak of the settled and very warm spell, just the risk of a few isolated heavy showers sparked by the heat but most areas fine and dry until early next week at least.

[Costa Del Fal]

I think it's fair to say that the background signals favour a trough probably just to our west in the 7-10 day timescale.We have a rather negative angular momentum level and with MJO moving into phase 3, this favours trough action close to the UK.Also to note is that the last stratopsheric warming hasn't receded yet so northern blocking could well be favoured.As others have said - enjoy it while it lasts!

Perhaps to be replied to me by PM or in the Summer 2013 thread to save clogging this thread up but what are your latest views in to the rest of summer? Surely not as bad as last year?

[ANYWEATHER]

Slow moving storms although probably well scattered look likely from Friday and more picticularly on Saturday and into Sunday according to gfs and ecm in the southern half of the Uk. Thereafter it becomes unsettled, but the devil is in the detail on this one as to how much rain is likely across the Uk...