Model Output Discussion 18z 28/07/13

[Frosty.]

It looks increasingly like that low at T+168 hours or thereabouts could be a brutal stormy feature across the far north with severe gales or even storm force gusts as it sweeps southeastwards, the low shown on the Gefs 06z control run gives you an idea of it's ferocity, the 6z mean makes it look more like a meerkat compared to the control run/op run roaring lion and support is growing for a genuine autumn storm heading our way by the start of next week, the latest met office update has added considerable weight to the idea of a disruptive depression bringing a much cooler and very unsettled spell to all areas by early next week which could last for most of next week BUT once again there is that longer range signal for a more benign anticyclonic and warmer spell for the last week or so of september and into october, however, it's fair to say the unsettled and cool spell in the shorter range has been beefed up a lot, this week still looks relatively benign to what is likely next week with some calmer sunnier days with overnight fog but fronts also sliding south and east from time to time, tomorrow looks thoroughly miserable across the far east of england in particular with gale force N'ly winds as a depression ejected from germany slides down the north sea, more rain spreading southeast on wednesday after a fine start in the south and thursday, friday and saturday look mixed with rain or showers around but quieter sunnier areas too, detail is not that easy to pin down.

Edited September 9, 2013 by Frosty.

[johnholmes]

something the anomaly charts missed-the very potent short snowy northerly blast in the Pontefract area with about 10cm of powdery stuff and temperatures down to -6C!!!

[picog]

something the anomaly charts missed-the very potent short snowy northerly blast in the Pontefract area with about 10cm of powdery stuff and temperatures down to -6C!!!

Is that what you had today John?

[johnholmes]

Is that what you had today John?

 

yes honest!

[Captain Shortwave]

 

Still looks nasty, and the northerly following will also be rather unpleasant.

Come back in two months time, then we will talk 

Edited September 9, 2013 by Captain shortwave

[Summer Sun]

Could next week see the first flakes on the Scottish mountains of Autumn 2013 GFS thinks so

 

If you look closely the white hatches are there, but as we can see this is only a short lived unsettled spell with pressure rising from the west quite quickly

 

[snowking]

Could next week see the first flakes on the Scottish mountains of Autumn 2013 GFS thinks so

 

If you look closely the white hatches are there, but as we can see this is only a short lived unsettled spell with pressure rising from the west quite quickly

 

Not so sure about the final prognosis, to me FI looks rather unsettled:

 

 

Brief ridge of high pressure:

 

 

Before becoming more unsettled once again:

 

 

As ever though it's only one FI run for now....I still suspect the second half of September will likely be rather more unsettled.

 

SK

Edited September 9, 2013 by snowking

[Sky Full]

What would it take to reverse the current set up, giving us a settled HP to the north east over Scandiniavia and LP systems swinging by to the south of us? Wouldnt that encourage an easterly flow of warm continental air to keep our temperatures up until it was really time for the serious cold stuff again? As long as the Azores high is unchallenged will we get increasingly cold N or NW air over us, coz I'm not ready to fire up the boiler yet!

[Tamara]

Face value output will tell us little or nothing at all a week away and whilst a reasonably deep autumnal low pressure system does seem more and more likely to track somewhere in the vicinity just to the north of Scotland, I would suggest that the GFS is overdoing the depth and strength of the low. I also remain, at least for the time being, sceptical about the suggested pattern thereafter

[Cloud 10]

Could next week see the first flakes on the Scottish mountains of Autumn 2013 GFS thinks so

 

 

 

 

 

. 

 

[MR EXTREMES]

[*]well back after a few days away from the model watching and as I suspected last week the models were always were creeping slowly towards a more normal autumn outcome which is good to see something more exciting at long last.

[*]It was a slow removal of the azores high but was really the most likely outcome.

I think it will now be a swift drive into autumn and the first cold snap for the north and as suggested something wintry over the mountains.

so not return of summer in the second half of September but something a little more wet and wild which for autumn which I like.

[Southender]

.

uksnowrisk.png

And so it begins again. Roll on winter!...

[Summer Sun]

ECM keeps the deep low on the 12z will be interesting to see if it takes the same route again

 

[ANYWEATHER]

 

[*]well back after a few days away from the model watching and as I suspected last week the models were always were creeping slowly towards a more normal autumn outcome which is good to see something more exciting at long last.

[*]It was a slow removal of the azores high but was really the most likely outcome.

I think it will now be a swift drive into autumn and the first cold snap for the north and as suggested something wintry over the mountains.

so not return of summer in the second half of September but something a little more wet and wild which for autumn which I like.

 

Tbh, I think you hit the nail on the head! Some members on here have swapped from looking at last minute heatwaves, to something akin to coldwaves!  Models are now gearing up for more of a traditional Autumn fest of stormy/unsettled weather. As for indian summer like weather ,well we can forget that scenario! but of course warm weather can be had early October,,, 

[Summer Sun]

The low is further north now on ECM

 

 

ECM has removed the low this evening with high pressure keeping it away

 

 

This is the 2nd time ECM has done this in the past month had a low over the UK only for it to end up missing us

 

Edited September 9, 2013 by Summer Sun

[No Balls Like Snow Balls]

The low is further north now on ECM

 

 

ECM has removed the low this evening with high pressure keeping it away

 

 

This is the 2nd time ECM has done this in the past month had a low over the UK only for it to end up missing us

 

 

And you can bet your bottom dollar every single model will show a different track of the LP in there next runs. It's still there.

As you well know it is notoriusly difficult to predict the track of a LP even some times only 24 hours out. 

The main thing is the LP is still showing on every model

Edited September 9, 2013 by No balls like Snow Balls

[Summer Sun]

High pressure builds in more at t216

 

 

[Frosty.]

The low is further north now on ECM

 

 

ECM has removed the low this evening with high pressure keeping it away

 

 

This is the 2nd time ECM has done this in the past month had a low over the UK only for it to end up missing us

 

The met office update today thinks the low will hit so it will be interesting what they say tomorrow, this could be a complete miss, a glancing blow or a direct hit.

[Summer Sun]

ECM ends warm and settled with +12 uppers appearing

 

[Frosty.]

ECM ends warm and settled with +12 uppers appearing

 

wow that would be some turnaround after the cold wet and windy outlook for next week from the MO..

[ANYWEATHER]

wow that would be some turnaround after the cold wet and windy outlook for next week from the MO..

Ha Ha Ha ,yes it would!! 

[Man With Beard]

ECM ends warm and settled with +12 uppers appearing

 

 

Bit of a turnaround from this morning? When ECM was all for a trough to the NE?

Must say I was going to call a change to a more unsettled outlook but tonight's ECM wants to turn that on its head - more runs needed!

 

[William of Walworth]

Some, like me are very keen to see models retaining some prospect of HP influence next week/later next week.

 

Some, like other posters here, are very keen to write off any further chance of HP having any significant influence.

 

As ever, different outputs can support different outcomes at different times. Depending on your personal preference for 7 to ten days time, you can find almost anything you want!

 

Late warmists** like me should be suitably cautious then, but so too should early coldists/wettists/

unsettledists! <-- new words?

 

**Or at least dryists ....

Edited September 9, 2013 by William of Walworth

[Frosty.]

The GEFS 12z control run is very interesting, we go from a very autumnal weather pattern with very cool, wet and windy weather to very summery weather again in a matter of days, this 12z control run best describes what the met office update described today, very cool with strong winds and rain followed by squally showers and then a gradual change to fine, warmer and sunnier weather during the last week of september and into october.

[Summer Sun]

Latest on the models from Gibby

 

Good evening. Here is the report on the 12 midday output from GFS, UKMO, GEM, NAVGEM and ECM for today Monday September 9th 2013.

 

All models show Low pressure to the East of the British Isles giving cold NW or Northerly winds down across the UK. Many areas will be dry from now but Eastern Coastal Counties will be cloudy with spells of rain and a very cold day for September tomorrow. This eases away East along with the Low pressure on Wednesday as a ridge topples SE across the UK. Following hard on it's heels is a series of fronts which bring rain SE across all areas later in the day with Thursday seeing unsettled and cloudy conditions predominating with further rain at times gradually clearing from the North on Friday but slow to do so in the South. Over the weekend the winds freshen markedly in the North on Saturday and more generally on Sunday as Low pressure winds up to the North of the UK.

 

GFS then shows early next week as a very turbulent spell with gale or severe gale force winds over Scotland and NE coastal counties as a vicious Low pressure slides past Eastern Scotland. As well as high winds for all rain would occur too, heavy for a time before being chased away by cold NW winds and showers by midweek. The Low pressure responsible then moves away North to be followed by a very changeable and Autumnal remainder of the run with spells of strong winds and rain alternating with cool and showery weather with the South too seeing some appreciable rain at times.

 

The GFS Ensembles tonight show considerable spread from the end of the week with most members showing very changeable but not always wet conditions with widely fluctuating temperatures from day to day and member to member. The Jet Stream is showing signs of getting into Autumn now with a much stronger flow at times than recently. It's position remains variable through this wee, mostly tumbling down over the UK from the NW. Later in the week and next week the flow strengthens on a strong West to East motion across Scotland or England.

 

UKMO tonight shows a deep Low winding itself up to the North of Scotland next Sunday with strengthening winds and rain sweeping East across most areas by the start of next week.

 

GEM tonight also shows the UK experiencing a swipe from a deep Low pressure travelling ESE close to NE Scotland late in the weekend clearing away East as we move into next week with a cool and showery

NW flow blowing ahead of a temporary looking midweek ridge.

 

NAVGEM too shows the weekend Low but further North and affecting mostly just the north with wind and rain while the South though cloudy and breezy would probably see  just a short spell of rain as the cold front weakens as it moves SE in the wake of the blow.

 

ECM tonight harmlessly takes the Low on a track well North of the UK with some affects to the North in the shape of windy weather with a spells of rain. Southern areas would maintain largely benign conditions with just short bursts of showery rain as weakening fronts pass by in association with that Low to the North. Late in the run and High pressure arrives back over the UK from the West with fine, dry and Autumnal conditions prevalent for all.

 

In Summary the weather remains less than certain for the period later in the week and the weekend. In the short term troughs moving down from the NW will deliver a lot of cloud for all this week with some rain at times, chiefly Wednesday and Friday in the South. Thereafter we have a variety of options shown ranging from raging gales, heavy rain  and cool conditions to more mundane conditions when there will be mostly cloudy skies with just patchy outbreaks of rain, less wind and temperatures close to average. The next instalment tomorrow morning will probably give us some more variable output maintaining the poor run that the models have had of late of predicting things more than 5 days out in a unified manner.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm