Model Output Discussion 13/11/13 >

[Cheshire Freeze]

http://modeles.meteociel.fr/modeles/gfs/runs/2013111412/gfsnh-0-252.png?12

 

reload arriving

S

 

PV being kicked from pillar to post

 

Edited November 14, 2013 by CreweCold

[SMU]

& proper reload ( 2010 ) at 300 as vertical advection over Eastern canadia

 

The vortex is shredded

http://modeles.meteociel.fr/modeles/gfs/runs/2013111412/gfsnh-0-300.png?12

[tight isobar]

Pv ablitarated, latter frames, encroaching, eastern Europe...

[Mucka]

Well no cut off high in deep FI but if that synoptic is close we would be unlucky to only get glancing blows, there would be a good chance of some prolonged severe cold a la 2010.

[Summer Sun]

UK on the western edge of the coldest uppers in FI

 

 

There is a good way to go yet before we can be thinking of a 2010 style repeat

 

Edited November 14, 2013 by Summer Sun

[Nick L]

UK on the western edge of the coldest uppers in FI

 

 

But it's FI and looking at details is futile. Just look at the PV on the final chart you posted though, it's utterly shredded! Bigger picture. Not details.

[The Northern Ramper]

Fingers crossed for the ECM.

[Yarmy]

But it's FI and looking at details is futile. Just look at the PV on the final chart you posted though, it's utterly shredded! Bigger picture. Not details.

 

The PV getting a good kicking has been the one consistent theme through all the recent GFS low rez.

[tight isobar]

ECM will be of major interest.

[SMU]

http://www.meteociel.fr/ukmo/runs/2013111412/UN144-21.GIF?14-17

 

UKMO middle of the road... somewhat slower than gfs with slightly less wave amplitude-

Edited November 14, 2013 by Steve Murr

[Nick L]

The PV getting a good kicking has been the one consistent theme through all the recent GFS low rez.

 

Indeed. It's been quite a trend over the last week, not long ago the pattern looked as flat as a pancake. 

[gottolovethisweather]

Just posted this on a couple of regionals so it has a Southern England bias, but I hope it is of use to some.

 

----------------------------------------------------------------------------------------------------------------------------------------------------------------

 

As of the 14th November we have seemingly stopped the zonal Atlantic train, at least for now. Here's an example cocurtesy of the GFS 12z as to why that should be the case.

 

The current NH Jetstream profile.

 

 

The current NH synoptic profile.

 

 

 

Despite the H500s looking rather warm, actual Air Temperatures over the coming days will likely only reach double-digits Fahrenheit in the warmer urban heat island areas.

 

At t+72 (12pm 17th November) the HP cell out West is showing signs of weakening and slipping back towards the Azores, as shown by the following.

 

The NH synoptic profile.

 

 

And the NH Jetstream profile.

 

 

 

So by this time, most places within the region will remain dry and settled, albeit fairly cloudy.

 

By t+96 (12pm 18th November) the fun begins.

 

The NH Jetstream profile at t+96 hours.

 

 

And the NH synoptic profile at t+96 hours.

 

 

As can be witnessed, a predominantly Northwesterly flow has enveloped the UK, colder air will be seeping South and the Atlantic remains blocked bar the NW air flow. Up to this point in time, I have my extremely high confidence in my forecast. Thereafter into next week, my confidence lessens due to potential disturbances i.e. surface features popping up in the aforementioned flow.

 

If we dare go out to t+120 (12pm 19th November) these charts look stonkers for the time of year with something similar to an Omega block in development out in the Atlantic?

 

The NH Jetstream profile at t+120 hours.

 

 

The blues are invading from the North and have infiltrated us past the South Coast by t+120 hours.

 

The NH synoptic profile at t+120 hours.

 

 

Air Temperatures by this stage could struggle to reach 40 Fahrenheit (5c and above) in this region, plummeting by night as a consequence under clear skies.

 

I see no reason in attempting to produce a forecast any further out than this as at such a timescale there will likely be many surface features, fronts, occlusions etc. to contend with and the Fax Charts will best guidance in such situations.

 

All the best

 

gottolovethisweather

 

*FWIW it does at this stage that things will be predominantly dry (this will likely change) and the Atlantic won't get a look in until at least the final week of November.

 

Edited November 14, 2013 by gottolovethisweather

[Snowfan50]

Id like to see the high pressure further west in FI to let the coldest uppers come west, otherwise they go into central Europe which is normal.

[The Northern Ramper]

http://www.meteociel.fr/ukmo/runs/2013111412/UN144-21.GIF?14-17 UKMO middle of the road...

Ukmo moving towards this mornings ECM? Uhoh.

[Mucka]

http://www.meteociel.fr/ukmo/runs/2013111412/UN144-21.GIF?14-17

 

UKMO middle of the road... somewhat slower than gfs with slightly less wave amplitude-

 

I don't like it.

Hopefully ECM will be closer to GFS

[Continental Climate]

I'm not too keen on the UKMO http://www.meteociel.fr/ukmo/runs/2013111412/UN144-21.GIF?14-17!! Not as much ridging north of our high looks likely to topple if we had a 168. Not that fussed though cold and frosty and foggy sounds good to me also

[terrier]

Ecm going to be of major intrest now. Dont really like the look of the ukmo if im honest.

[syed2878]

wo guys lets hold on to our horses remembor that ecmf? Lets waight til sat before we talk about 2010. Though these charts r excelent to look at.

[PolarWarsaw]

We will have to wait and see the ECM - but it appears this mornings UKMO/ECM are potentially onto a less severe snap than the GFS and that potentially the GFS is a little behind again. A big ECM 12z, but let's not forget this was only supposed to be a 'cold spell' - nothing prolonged, severe or particularly snow bearing. Just to keep that in mind and temper member expectations a little.

[shaky]

Ukmo not too bad to be honest!!you can tell its trying to undercut the high in the atlantic.i think by tomorrow we should see the ukmo come in line with the gfs!!

[Frosty.]

Arctic blast is in the bag, full house model agreement for a very wintry first half to next week, arriving in scotland on monday with the arctic air plunging south to all areas for tues and wed, yes there will be snow..darren bett just said so and he was grinning.

[swfc]

Quite odd really ?yesterday gfs was cannon fodder and ecm and ukmo were king?Does anyone really buy into gfs after 169 hrs atm .seems when it shows epic blocking and the pv being obliterated they do.Good or bad id stick with the euros and stick to the shorter time frames 

[Cheshire Freeze]

Don't know where we'd go from that 144 hr UKMO chart TBH. I think we'd get away with it eventually but it'd be a lot slower process and a tad more complex than the GFS route. The high can't easily be blasted into Europe due to solidly low heights there.

[The PIT]

Pretty impressive modelling all round. Picked up well into FI and brought into the reliable time frame with only relative modifications. ECM will probably now flip completely and show a one day toppler to wind us all up.

Looking forward to the weather warnings of doom and people panicking at the first snow flake.

[Summer Sun]

Well the Chris Fawkes did say Tuesday and Wednesday would see the peak for the cold weather and that looks the case with this afternoon's UKMO