Model Output Discussion 18th Nov.2013-12z onwards.

[Snowman.]

Much lower heights going into Europe on this run.

 

[MPG]

Thanks for the update Ian. Perhaps not enough there to make most folk ecstatic, but at least enough to stop them becoming further depressed - note most tho...

Not sure you actually read Ian's post correctly? The bit about the amplification in the Atlantic.........

 

and further depressed about what? The weather right now is cold, not mild, no SW winds etc etc.

Edited November 24, 2013 by MPG

[Mucka]

GFS still staggering around like a drunken sailor looking for a whore, best ignored for now.

 

Edited November 24, 2013 by Mucka

[Great Plum]

What are the 'decider models', Steve? Will the weather not just do what it does?

I think that DECIDER is a met office mid range model that we don't get to see...

[lorenzo]

Re Decider, see link here http://www.metoffice.gov.uk/media/pdf/l/f/decider.pdf or in the presentation linked below

 

https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&ved=0CD0QFjAC&url=http%3A%2F%2Fwww.ecmwf.int%2Fpublications%2Fmember_states_meetings%2FForecast_products_users%2FPresentations2011%2FPDFs%2FMylne_Parker.pdf&ei=9yiSUq3_Ku7e7Aaek4DoCw&usg=AFQjCNFVmcgEv7GBfuPKhaey_KTsZKD0bQ&bvm=bv.56988011,d.d2k

 

Looks brilliant, clusters ensembles into regimes to provide an outlook on predicted weather type, if anyone wants a run through Dec 81 click here..

 

Edited November 24, 2013 by lorenzo

[Summer Sun]

Other than the odd short cold snap GFS once more keeps pressure high over the UK

 

[Snowman.]

Latest CFS 9 month still keeping us in cold conditions with positive heights north and negative heights south for the entire winter.

 

Actually looks a lot like '81 now that I think about it lorenzo.

Edited November 24, 2013 by SN0WM4N

[Summer Sun]

Quick update on the issues with UKMO between t06 and t36

 

Lack of data for UKMO cards between 6 and 36h! Thank you for your understanding!

 

Data missing for 0-36h UKMO charts, sorry for the inconveniance!

Edited November 24, 2013 by Summer Sun

[snowmadchrisuk]

Other than the odd short cold snap GFS once more keeps pressure high over the UK

 

 

I see the old Arctic High is trying to build

[johnholmes]

Re Decider, see link here http://www.metoffice.gov.uk/media/pdf/l/f/decider.pdf or in the presentation linked below

 

https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&ved=0CD0QFjAC&url=http%3A%2F%2Fwww.ecmwf.int%2Fpublications%2Fmember_states_meetings%2FForecast_products_users%2FPresentations2011%2FPDFs%2FMylne_Parker.pdf&ei=9yiSUq3_Ku7e7Aaek4DoCw&usg=AFQjCNFVmcgEv7GBfuPKhaey_KTsZKD0bQ&bvm=bv.56988011,d.d2k

 

Looks brilliant, clusters ensembles into regimes to provide an outlook on predicted weather type, if anyone wants a run through Dec 81 click here..

 

 

all I can say is gordon bennett-thank gawd I am no longer working as a forecaster!

far too complex for my sinple mind

Edited November 24, 2013 by johnholmes

[Summer Sun]

I see the old Arctic High is trying to build

 

Aye its back in FI

 

 

Very deep low heading for Greenland

 

[Joe Levy]

My favourite chart of this GFS 12z run, though it is FI

[East_England_Stormchaser91]

Look at that for some WAA in FI. Also to note, some real cold air heading to us from Scandi -15 uppers. That PV looks to be cruising for a bruising if the outlook is to be believed.

[Cheshire Freeze]

Look at that for some WAA in FI. Also to note, some real cold air heading to us from Scandi -15 uppers. That PV looks to be cruising for a bruising if the outlook is to be believed.

 

Yep and all initiated by Pacific ridging. As I said yesterday, regardless of stratospheric temps etc etc there's only so long the PV can remain intact under such pressure. It's not a pattern that can be maintained for very long without ramifications to the PV with time (hence my reference to the upcoming 'holding pattern' yesterday afternoon. The FIs of some of the recent GFS runs (along with the GEFS) maintain the suggestion of an erosion of the western portion of the vortex over time, with troughing dropping into Scandinavia/Russia as the core of the PV is forced to the Siberian side of the hemisphere. This is why we're seeing some GEFS perturbations which completely smash the vortex and promote proper height rises towards Greenland.

 

This chart is a graphical representation of the point RE western vortex disintegration

 

 

 

Edited November 24, 2013 by CreweCold

[Mucka]

MetO not brilliant but not bad and compared to GFS it is light years ahead for potential cold and likely accuracy for that matter.

 

Edited November 24, 2013 by Mucka

[cooling climate]

Very promising trends from the charts this afternoon for the extended range

by GFS and UKMO. Looking forward to seeing the ECM 12z a bit later.

[Summer Sun]

UKMO shows the pressure moving east again at t144

 

 

Comparison of GFS and UKMO at t144

 

Edited November 24, 2013 by Summer Sun

[Mucka]

GEM moving away from a deep trough affecting the UK later bringing the prospect of something colder and siding with GFS's limpet high 

 

[Cecil Hogmanay Melchett]

GEM moving away from a deep trough affecting the UK later bringing the prospect of something colder and siding with GFS's limpet high 

 

Predictable really.

Im afraid the output continues to really flatter to deceive,(if you'll pardon the unintended pun)

Any talk of Dec 1981 is to be frank,a bit bizarre...

Edited November 24, 2013 by happy days

[Ian Brown]

Very promising trends from the charts this afternoon for the extended range

by GFS and UKMO. Looking forward to seeing the ECM 12z a bit later.

 

I don't agree - for me there is nothing to suggest HLB, for sure the chances of brief NWerley incursions, but I don't see anything in the output that deviates from the METO outlooks for early December.

[Mucka]

GEM at least shows some promise by day 10

 

 

Not to over analyse a day 10 chart but just to explain the promise for people just learning to read charts.

 

The low pressure over Iceland would develop and run s/se while the low to the sw of the UK would remain in situ and slowly fill this means the Atlantic ridge can not sink or be quickly toppled East by low pressure on its Western flank which would cause WAA NW into Greenland with a NE flow likely following.

Edited November 24, 2013 by Mucka

[Cheshire Freeze]

GEM at least shows some promise by day 10

 

 

The low pressure over Iceland would develop and run s/se while the low to the sw of the UK would remain in situ and slowly fill these means the Atlantic ridge can not sink or be quickly toppled East by low pressure on its Western flank which would cause WAA NW into Greenland with a NE flow likely following.

 

GFS control showing the same promise at day 10 and once again follows the western vortex erosion route

 

 

[TSNWK]

Please can someone advise on what the GFS control run is? Does it verify etc.

[Captain Shortwave]

Good support for a HLB over Alaska and stretching down the west coast of Canada going into week 2. But I remain very cautious about it's impacts for our part of the world. As the phrase goes, fool me once, shame on you. Fool me twice, shame on me. Not going to get excited unless something appears towards the latter part of week 1 which might suggest something might actually verify.

Edited November 24, 2013 by Captain shortwave

[Tim Bland]

I think things could get exciting into the 2nd week if December. With the PV shunted east and higher pressure over Greenland