Model Output Discussion 18z 28/07/13

[Captain Shortwave]

ECM showing a north/south split as next week progresses, but as the weekend approaches its downhill for just about everyone

Sundays chart!

Treat a chart like that with extreme caution. With the profile over Greenland as it is, I find a meridional pattern over the UK to be rather unlikely. 

Later half of next week looks good. Probably some rain late Friday, next weekend who knows but I suspect the Azores high will have an influence still, especially in the south.

Edited August 9, 2013 by Captain shortwave

[The Northern Ramper]

Agreed Captain, the ECM ensemble mean could be telling, I have a feeling that was at the bottom end of the spread......

[Frosty.]

After a cooler and showery mon/tues, the Ecm 12z starts to look very nice by the middle of next week with a strong pressure rise bringing a few fine and increasingly warm and sunny days as temperatures rise in to the mid 20's celsius across the southern half of the uk, perhaps nearer the high 20's celsius, into the low 80's F across the south/se but with a thundery breakdown next friday, another ridge begins to build in from the southwest although on this run, it gets flattened by a large shallow trough drifting southeast from iceland across the north of the uk, however, this just looks like a brief wobble to me because T+240 hours is setting up a surge of very warm and humid 564 dam air to begin to push up from western france once that spoiler trough has pushed away to the northeast, at least that is how I see it going beyond the end of the ecm run, all in all, trends look very promising, especially from the latest Gefs 12z mean, let's hope tomorrow will look even better.

Edited August 9, 2013 by Frosty039

[legritter]

Evening all ,looking at tonights modells data etc i would say nothing of anything newsworthy in outlook except where high pressure sets up after 8/10 days time will dictate any warm spell or cooler west or even northerly type weather ,but of course many variations on this theme is possible but we certainly have had a good summer so far apart from some small blips .but i do have a gut feeling that eventually we will see what i call an interesting spell of weather ,possibly in about 2 wks time just gut feeling but i think present climate on a big scale is in a quick change artist mode ,certainly not boring this weather hobby ,just had a look at sunset ,and more manmade clouds [Contrails ] than natures clouds , .

[draztik]

Treat a chart like that with extreme caution. With the profile over Greenland as it is, I find a meridional pattern over the UK to be rather unlikely. Later half of next week looks good. Probably some rain late Friday, next weekend who knows but I suspect the Azores high will have an influence still, especially in the south.

just as you should treat the gfs run with caution, as the ensembles show the op was an outlier, with more members indicating cooler temps!

[Captain Shortwave]

just as you should treat the gfs run with caution, as the ensembles show the op was an outlier, with more members indicating cooler temps!

If you are talking about low resolution then yes. In fact I've not really looked many operationals beyond T192 for that reason as a plume at T300 is not going to verify. What I am looking at is the ensemble mean which shows a significant pressure rise beyond the 20th August as that is a definite trend. As I said last night I will be interested next week as the GFS high pressure scenario comes into the range of the 10 day ECM charts. We can see to see whether the ECM follows this trend.

There is logical reasoning behind why the last frames of the ECM don't look right, mainly because having an upper vortex over Greenland would naturally mean higher than normal heights over Iberia and France which suggests a NW/SE split in the weather which the ECM doesn't show despite having low heights over Greenland. Hence my deduction that the ECM has dug the trough far too south like it has done on latter frames for most of the summer. Simply put, I almost guarantee the ECM will correct northwards in the coming runs.

GFS trend still there

Edited August 9, 2013 by Captain shortwave

[mushymanrob]

GFS yet again raises pressure at the end of its run, both op and ensembles - done this several times now

I'm starting to take notice. Wouldn't be the first time a consistent trend from GFS at this range turns out right. 

 

im in agreement with you, it is something that keeps cropping up in the runs albeit fi, but is worth noting... plus..

 

it does have some support... so just maybe theres something really warm to end the month on... (but this is a long shot atm)

 

before then theres a cooler spell early week before it warms up abit... next week does look pretty nice, pleasant, and enjoyable. we should get some decent spells of sunshine, but away from the southeast it doesnt look like we will get high temps, low-mid 20s by thurs.

 

before the clutched straw the gfs hints at in fi, next weekend appears to have a large, deep trough heading our way. but thats in fi, until then enjoy a reasonable week.

[draztik]

This mornings runs are rather disappointing for summer fans wanting a return to heatwave conditions anytime soon. The gfs doesn't show HP building in wide scale until the very end of its run, while the ecm up to 240 shows bands of low pressure crossing the UK up to this stage. Next week tho will feel fairly pleasant, the more south you live!

even if the gfs is correct, a return to July heat looks unlikely. It will however be pleasant, perfect weather to end summer the daily express headlines, given the models today, appear reckless and absolute nonsense.

Edited August 10, 2013 by draztik

[Summer Sun]

This mornings runs are rather disappointing for summer fans wanting a return to heatwave conditions anytime soon. The gfs doesn't show HP building in wide scale until the very end of its run, while the ecm up to 240 shows bands of low pressure crossing the UK up to this stage. Next week tho will feel fairly pleasant, the more south you live!

even if the gfs is correct, a return to July heat looks unlikely. It will however be pleasant, perfect weather to end summer the daily express headlines, given the models today, appear reckless and absolute nonsense.

 

 

The GFS ensemble sort of agrees with the Op at t192 the slight difference is the centre of the low is further north

 

 

T312 though I pleased to say it does not agree at all instead the ensemble prefers to build pressure in

 

 

And that leads to a nice settled bank holiday weekend

 

[Captain Shortwave]

The GFS ens high pressure trend is still there and is now starting at day 11

 

So will the ECM start to pick this up in it's upcoming runs? Interesting times ahead.

Edit - ECM mean showing pressure rising from the south at day 10

Edited August 10, 2013 by Captain shortwave

[shedhead]

That's the Daily Excess for you...never let facts get in the way of a good story...

 

 

The same could well be said about the current model outputs too, with the mixed, (even rather unsettled in the north) spell next week the main story and the possible pressure rise towards months end being nothing more than rather wishful thinking at this stage.

 

For the south though next week again looks pretty decent without being spectacular, which imo sums up August to date and will probably sum it up completely come Sept 1st.

Edited August 10, 2013 by shedhead

[TootyFruity]

Hi Summer Sun is the high pressure still building in for weds next week and If so how would Filey/Scarborough be doing in that set up ?

Thanks

TF

[Frosty.]

A few nice and warm days next week according to the Gfs 00z, the warmest weather across the southeast with temperatures in the mid 20's celsius but generally low 20's c, less warm and more generally unsettled further northwest with monday looking particularly unsettled across the northern half of the uk, by tuesday it looks brighter and drier with sunny spells and just a few light showers, midweek warmer, drier and sunnier across the southern half of the uk, thursday some heavy showers around but still with some sunshine and warm again in the southeast, average temps elsewhere, friday fine in the south but more unsettled further north and west, unsettled next weekend with average temps and then into the following week it shows high pressure building across the uk and migrating to the east with a few more fine and warm days but becoming more unsettled in the west.

Edited August 10, 2013 by Frosty039

[Summer Sun]

Hi Summer Sun is the high pressure still building in for weds next week and If so how would Filey/Scarborough be doing in that set up ?

Thanks

TF

 

Unfortunately GFS shows the high getting pushed away by Wednesday it should start dry but rain looks like arriving during the afternoon from the west of course Wednesday is still a while off yet in weather terms so anything could happen yet

 

[draztik]

Northern Ireland appears to be in for a soaker the next week or so! While the South sees some pleasant summer weather! I hope conditions improve for our NW friends.

Edited August 10, 2013 by draztik

[draztik]

Also, interesting to see the extended 5 day forecast for London on the bbc weather page. It has a temperature range of 16-30C for Friday 19th! In Belfast its 14-22C!

Edited August 10, 2013 by draztik

[Frosty.]

The GEFS 00z control run mean shows a spell of anticyclonic and pleasantly warm weather developing through next week but staying more unsettled across the north of the uk, temps rising to low to mid 20's celsius in the south/se but nearer 16-20c for the north, there is a nationwide unsettled and cooler blip next weekend into the start of the following week and then high pressure builds in again from the southwest, for cumbria,n.ireland & scotland it's mostly unsettled with average temps but occasional fine and warmer interludes but further south the balance becomes more even across central parts of the uk and for the south of wales across to the midlands and east anglia southwards, it's 70/30 in favour of fine and reasonably warm conditions with only brief flirtations with cooler more unsettled weather. Eventually the mean shows a large atlantic anticyclone slowly drifting east with the north joining the south in a more settled further outlook.

[Frosty.]

That FI atlantic high looks familiar..

[MR EXTREMES]

from what I can see my thoughts from lastnight look pretty realistic with collapse of heights with more mobile alantic westerly northwest flow.

this taken from the ukmo and gfs with that low pressure pushing heights futher south and east.

 

 ukmo at t144

 

ecm at t144 slightly delayed but same evolution

gfs slight differences but same evolution I think the alantic is ready to fire up and this is to be expected as its been a very long quiet spell heres the gfs at t144

 

over all a few if not a week of fairly ok weather with warm days and nights.

this evolution has shown signs of building towards a more mobile theme for a few days now but I would like to stress things can still change but I believe its a little more unsettled by weeks end.

[MR EXTREMES]

and the gem beyond t144 absolutely fires up the alantic early autumn anyone fi but realistic

[draztik]

and the gem beyond t144 absolutely fires up the alantic early autumn anyone fi but realistic

absolutely true, the gem is much more mobile than the other models. It ends its run with

, so this hp that gfs is showing is by no means nailed on!

Edited August 10, 2013 by draztik

[Captain Shortwave]

hmm not sure what I think of the GFS ens, it's showing the operational as an unsettled outlier for next weekend into the following week with the low much further north.

 

Compared with the op.

 

Which is pretty similar to other models at this timeframe. (well ECM/GEM are actually worse)

I was starting to think of next Sunday being a potential write off but with a mean like that, maybe the models are digging the trough too far south again.

Beyond next weekend, there is still strong support of a pressure rise from the south from the 20th/21st August.

[summer blizzard]

Aye, all models have low pressure close to the UK at day 7-9 so i'd be inclined to ignore the ensembles.

[MR EXTREMES]

hmm not sure what I think of the GFS ens, it's showing the operational as an unsettled outlier for next weekend into the following week with the low much further north.

 

Compared with the op.

 

Which is pretty similar to other models at this timeframe. (well ECM/GEM are actually worse)

I was starting to think of next Sunday being a potential write off but with a mean like that, maybe the models are digging the trough too far south again.

Beyond next weekend, there is still strong support of a pressure rise from the south from the 20th/21st August.

I think its knife edge stuff but its been a evolving situation for the last few days and I may be wrong but its all slowly heading towards a mobile situation,what will tonights outputs bring???

still betting on a slow sink of heights to our south but perhaps behind the low heights from the alantic a build of heights but bottom line is will we be stuck with low pressure close or over the uk.

 

we shall see.

[MR EXTREMES]

the Jetstream profile shows how the alantic inroads of low pressure is coming into place as early as t72 u can see the surge of jet energy coming straight at us but as suggest knife edge