Model Output Discussion 1200 hrs 30/09/14

[Frosty.]

Did someone order a sausage sandwich? will it be red sauce, brown sauce or no sauce at all

 

As for the models, It looks to me like we are going to be using the words north / south split quite a lot in the weeks ahead because by the end of the week high pressure will be building in from the southwest but the probability is it will only influence the southern half of the uk with the north staying generally unsettled, it also looks colder at times in the north of the uk with showers turning wintry on higher hills between bouts of wet and windy weather and the south is likely to see an increasing risk of fog and night frosts.

Edited October 19, 2014 by Frosty.

[Captain Shortwave]

Well I call it deep FI very unlikely too happen

3 consistent runs which have been backed up by its ensembles, maybe it is the GFS that is a little lost. To be honest for anyone looking for cold then those final charts are not too bad. You would be looking for that high to build northwards as it links to the Siberian high with cold air piling south into the Atlantic and pushing west from the low over Eastern Europe.

As for the conditions, starting warm before surface temperatures drop with foggy nights.

[bluearmy]

dont let steve see the end of the ecm run - far too early in the year for him to get this excited !!!

[The PIT]

3 consistent runs which have been backed up by its ensembles, maybe it is the GFS that is a little lost. To be honest for anyone looking for cold then those final charts are not too bad. You would be looking for that high to build northwards as it links to the Siberian high with cold air piling south into the Atlantic and pushing west from the low over Eastern Europe.

As for the conditions, starting warm before surface temperatures drop with foggy nights.

So far out I wouldn't worry. We haven't got the stage where T216 is even remotely reliable.

[SMU]

SAI RECORDS SMASHED... Will be the headline if the ECM verifies.

 

Almost PERFECT conditions for deep snowcover west of Russia by the end of the run, completing a bonanza month on the snow advancement index.

 

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=1&type=0&archive=0

S

[ANYWEATHER]

A much more mobile unsettled week ahead with some stormy conditions from ex-gonzalo late monday into Tuesday Then the changeable/unsettled conditions prevail with alternating  cold and mild spells prevail, its only the last stages of both ecm and gfs differ, ecm settled ,gfs unsettled.

[Frosty.]

I hear we are in for a weak El Nino this winter which would mean a higher chance of the usa (north america) having a relatively milder and wetter rather than colder snowy winter again which can only be good news for the uk? I think the myth that the usa snow storms reaches the uk a few weeks later was well and truly busted earlier this year, we got rain instead but hopefully the northern blocking will return this time.

 

So it's Goodbye Polar Vortex, into the shredder for you and hello El Nino

[knocker]

Quite good for a laugh. 28C in Stornoway Hey Ho said Rowley.

Edited October 19, 2014 by knocker

[Captain Shortwave]

ECM ens again back the operational

#

 

GEM is not having any of this from the ensembles and the GFS is much slower but eventually builds high pressure over the UK. Which one is going to be correct?

Either way the tropospheric vortex looks like it will continue to struggle in its initial development.

[knocker]

I believe somebody has already mentioned perhaps the GFS is the odd one out. The ECM certainly goes with the Greenland trough, but orientated a tad NW/SE and then builds the HP from the south stretching to the HP in the Arctic. In the longer term weakening of the heights (to be expected) and no great amplification upstream. Temps above average.

 

Where's the PV?

Edited October 19, 2014 by knocker

[bluearmy]

Deep fi ECM ens mean and anomalys beginning to look a tad retrogressive??

[Midlands Ice Age]

Quite good for a laugh. 28C in Stornoway Hey Ho said Rowley.

 

Knocks .....

 

I don't understand the chart you have posted above .......

 

The max temp at the top is 21C anywhere in the NH. Where is the 28c in Stornoway?

 

But even worse, the chart is described as a wind anomaly chart yet it shows the wind arrows going  clockwise around the low off Scotland. I always thought they tracked anti-clockwise in the Northern Hemi 

 

I guess the first was a  correction of some sorts, but I still don't understand  the wind arrows. 

 

MIA

Edited October 19, 2014 by Midlands Ice Age

[bluearmy]

It's an uppers temps chart MIA. Highest reading on there far sw of Spain @ 21c. And the winds rotating around the block in a clockwise direction.

Not sure where Knicks gets a surface temp of 28c though??

Edited October 19, 2014 by bluearmy

[knocker]

Deep fi ECM ens mean and anomalys beginning to look a tad retrogressive??

 

Did cross my mind but a bit tenuous at the moment.

[knocker]

It's an uppers temps chart MIA. Highest reading on there far sw of Spain @ 21c. And the winds rotating around the block in a clockwise direction.

Not sure where Knicks gets a surface temp of 28c though??

 

No that would require an improbable (impossible) lapse rate I agree b. I admit I wasn't taking it seriously.

Edited October 19, 2014 by knocker

[Polar Maritime]

The PV looks obliterated towards the end of the GFS, High uncertainty continues into week 2 with such strong high latitude blocking.

 

  

[knocker]

Last night blue mentioned possible retrogression. Still on the cards?

 

Edited October 20, 2014 by knocker

[MR EXTREMES]

Was in deep thought over the models last night and although a lot seem to suggest that no body knows whether the later fi runs are unlikely to come to fruition!

But one thing is certain the vortex is not a touch on last year,

and there is consistent runs from all models on high lat blocking it's also clear that it's very 09/10 in the over all atmospheric conditions to 09/10.

I personally expect the over all pattern is unlikely to change dramatically even with heights over the uk it's a good starting point !

In 09/10 the Azores high was very much a player and helped with the over all build up into what I'd say was the best winter I'd seen since the 80s.

Ok so there's no need to get the shovels out yet but the building blocks for a different winter outlook is coming along nicely.

And although the longer range models are completely lost at the moment the four main forecasting models are pretty much in tune apart from the finer detail.

It could well be that were heading towards more of a colder settled winter but still it's getting a little more interesting as each day passes.

[Frosty.]

The PV looks obliterated towards the end of the GFS, High uncertainty continues into week 2 with such strong high latitude blocking.

 

  

R.I.P....PV

[Polar Maritime]

Can we try and only discuss the "Model Output" in here. As interesting as it is, There are other threads for Winter discussion and patterns.

 

Many Thanks, PM.

[bluearmy]

The nuances of the 00z ECM op are probably more preferable to yesterday's 12z, given the time of year.

A general evacuation of low heights from the polar field and a nice looking Aleutian ridge.

[Eugene]

http://www.wetterzentrale.de/pics/Recm2402.gif - Exceptionally warm end to October likely, maybe 20C reached in the SE and more daily CET records smashed.

[ANYWEATHER]

http://www.wetterzentrale.de/pics/Recm2402.gif - Exceptionally warm end to October likely, maybe 20C reached in the SE and more daily CET records smashed.

Youre looking at ten days away, that chart wont verify that far out and given the recent poor model accuracy of late!

[Gibby]

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY MONDAY OCTOBER 20TH 2014.

 

NEXT UPDATE TUESDAY OCTOBER 21ST 08:00

 

THE CURRENT GENERAL SITUATION. A deepening Atlantic Low containing the remains of Hurricane Gonzalo will move East across Northern Britain tonight and tomorrow with a strong and colder NW flow following active fronts crossing East over the UK through the same time period.

 

MODELS-2 WEEK HEADLINE  Changeable weather with rain at times but some drier and brighter periods across the South. Near or slightly above average temperatures. Rather windy at times in the North.

 

THE JET STREAM ENSEMBLE FORECAST The Jet flow has changed it's orientation to lie in a West to East flow across Britain later in the week. It then becomes complex and undulating both North and South across the vicinity of 50-55deg North across the Atlantic and the UK next week.

 

GFS The GFS operational today shows a changeable period of weather across Britain for the next two weeks. The basic pattern is for Low pressure to the North and High pressure to the South staying the main weather patterns expected across our part of the world over the whole period. As a result troughs crossing East in the Westerly flow will bring rain and wind at times chiefly to the North. In the South drier and brighter conditions are likely but as troughs creep down from the NW and stall or develop waves some rain at times can also be expected here too between the brighter periods. With generally Westerly winds it would stay relatively mild.

 

THE GFS ENSEMBLES. The GFS Ensembles agree entirely with the operational within the framework detailed above with the best of drier and brighter weather always towards the South and East as Low pressure repeatedly crosses to the North and NW of the UK with rain and strong winds but always in relatively mild conditions.

 

UKMO UKMO this morning shows a deep Low to the North of the UK and High to the South keeping Westerly winds and the risk of rain at times going through next weekend especially in the North.

 

THE FAX CHARTS  The Fax Charts show warm sector conditions developing later in the week and weekend with rain and drizzle in places towards the West and North especially. By Day 6 a cold front moving East brings fresher air over from the West.

 

GEM The GEM operational shows a strong build of pressure across the South through next weekend and beyond with dry and bright weather but with overnight mist and fog patches. Further North a Westerly flow maintains damp and cloudy but mild weather with a little rain at times.

 

NAVGEM NAVGEM keeps Westerly winds across all areas next weekend with High pressure close to the South. Fronts crossing the North would bring some rain at times while Southern areas see less chance of this but overall there will be a lot of cloud. 

 

ECM The ECM operational today looks a lot like GEM with High pressure nudging up from the South over next weekend and the start of next week with progressively dry and benign weather affecting the South while the North remains in Westerly breezes with a little rain at times over hills and mountains. It looks like it will remain quite mild with mist and fog possible in the South by night later.

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend remains for mild Westerly winds to persist across the UK with pressure rising over the South with time.

 

MY THOUGHTS  Despite the very volatile conditions across the UK over the next few days the pattern looks largely uneventful and at times benign across the UK especially over the South. With Low pressure tracking Eastwards throughout the period to the North of the UK Westerly winds will remain prevalent. Pressure will become High close to or even over the South as we move into week 2 bringing quiet and mostly dry if rather cloudy conditions across the South then with any overnight breaks in the variable and often large amounts of cloud permitting the formation of mists and fogs. The polar front will be instrumental as the demarcation zone between dry and bright weather and more showery weather to the North at times with a band of thick cloud and occasional rain and drizzle being likely to be over Central Britain at the end of this week before moving North next and extending the influence of the better weather already over the South. While this pattern of weather remain and the belt of High pressure persists from the Azores to Europe then the weather will likely to be remaining mild and I see no immediate change on this overall pattern anytime soon given the Jet Stream profile currently and forecasted over the Northern hemisphere over the next few weeks.

[knocker]

Cold front across the Midlands?