Model output discussion - 5th December 2016 - Into Winter we go

[Singularity]

31 minutes ago, mb018538 said:

Not really sure what to make of the UKMO 144 hour chart tonight....I've got a bit of a sinking feeling though. I think the vortex/trough is going to disrupt things enough to make it mainly unsettled here.

 

 

Well it would seem that UKMO (right) has first disrupted the shortwave far more than GFS (left) at +120, and second managed to retract the Azores ridge so fast that the trough disrupting against the block is unable to become a cut-off feature. That then progresses to either 'scoop out' the trough from Iberia if the jet is aligned W-E, or drive further low heights under the block if the jet is aligned NW-SE.

I have presumed the lack of clarity going forward is what you meant by 'don't know what to make of it', but thought this analysis was worth doing anyway 

[Dancerwithwings]

43 minutes ago, Dancerwithwings said:

Yes! GFS at h192...BLOCK....Where will this lead us....?

Edit....Will be a place both wonderful and strange :-)

The control has the Anom HP moving north on this run

       GEFS member 18  

[Summer Sun]

Is it me or is GFS taking longer than normal to update on Netweather tonight?

[I remember Atlantic 252]

1 minute ago, Summer Sun said:

Is it me or is GFS taking longer than normal to update on Netweather tonight?

definitely taking longer, and frames missing

[Ali1977]

A fair bit of blocking showing in the ENS, with some really interesting set ups.  I have a feeling that something pretty special could crop up for coldies without any great notice late Dec. 2,5,7,18, and 20 in FI are pretty impressive but can't post them sorry.

Edited December 13, 2016 by Ali1977

[chris55]

GFS op dull (haven't looked at the ens yet, or caught up generally).....but UKMO on the other hand is full of potential!

[nick sussex]

Latest from the Global Tropics Hazard outlook:

There is a high degree of uncertainty for how any intraseasonal signal evolves over the next 1-2 weeks. Dynamical model forecasts of the RMM index and statistical forecasts of the MJO predict predominately weak MJO activity over the next two weeks, but some potential exists for the enhancement of convection across the western Pacific during Week-2. The low confidence forecast of the evolution of the tropical intraseasonal signal over the next 1-2 weeks makes it a challenge to reliably state both potential tropical and extratropical impacts linked to the MJO for the second half of December.

If high pressure remains to the east then what the MJO does could be the deciding factor in whether upstream amplitude helps to get some lower heights under the block. At the moment theres too much energy spilling east over the block and more amplitude might help hold the PV further west with the jet angling more nw/se.

 

[bluearmy]

5 minutes ago, Ali1977 said:

A fair bit of blocking showing in the ENS, with some really interesting set ups.  I have a feeling that something pretty special could crop up for coldies without any great notice late Dec. 2,5,7,18, and 20 in FI are pretty impressive but can't post them sorry.

the trend on the blocked cluster is retrogressive to our north. looking at the way some of the recent eps anomolies have ended there may be something in this.

[Ali1977]

3 minutes ago, bluearmy said:

the trend on the blocked cluster is retrogressive to our north. looking at the way some of the recent eps anomolies have ended there may be something in this.

The GEM shows a large 1060hp around NE Scandy and Western Russia, it does filter some very cold air into central Europe and wouldn't take much of a change in set up to hit us, not sure that is the type of scenario that will occur listening to you more knowledgeable types though.

[chris55]

The difference between GFS and UKMO at 144 highlights that if we can get some energy disrupting against the euro high at this timescale then the door will potentially open a much more favourably blocked pattern.

GFS 144, atlantic coming over the top!

UKMO 144,  major trough disruption with the energy heading into Iberia!!!

 

[Dancerwithwings]

27 minutes ago, Ali1977 said:

A fair bit of blocking showing in the ENS, with some really interesting set ups.  I have a feeling that something pretty special could crop up for coldies without any great notice late Dec. 2,5,7,18, and 20 in FI are pretty impressive but can't post them sorry.

 

20 minutes ago, bluearmy said:

the trend on the blocked cluster is retrogressive to our north. looking at the way some of the recent eps anomolies have ended there may be something in this.

All to what Ive being hinting at regarding the HP anomalies in my last few post's,

OK it's obverse well in FI and all that, but you both in a fashion mentioned.....Will it, won't it.....Time will tell

Edited December 13, 2016 by Dancerwithwings

[gottolovethisweather]

That is some odd looking D3 chart on the ECM, four to five surface lows (encircled in red) lined up along the Southern edge of the Canadian Vortex? Our friends are encircled in black, although the Euro high could be a foe if it doesn't behave as us coldies would like.

Take the above chart for Friday with a generous dosing of salt regarding the actual specific features, but more broadly, a linking up of extensive heights is incoming by the end of the working week into the weekend. Can we promote these heights further North and further North East in time, I hope we can. The following chart was predicted by the ECM 12z for this Friday, some three days ago.

A fair few differences there at the micro level but not at the global scale as such, yet this was only a t+144hours chart hence the uncertainties moving forward, other than a few days of HP influence which are nailed IMHO.

 

 

Edited December 13, 2016 by gottolovethisweather

[bluearmy]

Wow - look at that monster cold Siberian ridge at day 7 on ecm

 

[January Snowstorm]

It looks to me this evening that the models are firming up on a very unsettled and possibly stormy run up to Christmas.

Our best hope of a white one possibly from a Northwesterly direction.

Re long range models like Glosea etc.....sorry but I've lost all faith here. They couldn't be more off the mark and a lady with  crystal ball would do better. NONE predicted the end result for most of December which was a dominant Euro high retrogressing to Bartlett type.

I still think this Winter could be special just going on pure gut instinct. Here's hoping anyway

[feb1991blizzard]

5 minutes ago, bluearmy said:

Wow - look at that monster cold Siberian ridge at day 7 on ecm

 

Imagine the surface temperature.

[northwestsnow]

7 minutes ago, bluearmy said:

Wow - look at that monster cold Siberian ridge at day 7 on ecm

 

And low pressure over Italy,on the other side of the coin we are looking at a PV on steroids!

[shotski]

3 minutes ago, January Snowstorm said:

It looks to me this evening that the models are firming up on a very unsettled and possibly stormy run up to Christmas.

Our best hope of a white one possibly from a Northwesterly direction.

Re long range models like Glosea etc.....sorry but I've lost all faith here. They couldn't be more off the mark and a lady with  crystal ball would do better. NONE predicted the end result for most of December which was a dominant Euro high retrogressing to Bartlett type.

I still think this Winter could be special just going on pure gut instinct. Here's hoping anyway

Where are you seeing that ?

[BLAST FROM THE PAST]

11 minutes ago, bluearmy said:

Wow - look at that monster cold Siberian ridge at day 7 on ecm

 

Ecm looks like the worst run of winter to me.  

 

BFTP

[chris55]

3 minutes ago, January Snowstorm said:

It looks to me this evening that the models are firming up on a very unsettled and possibly stormy run up to Christmas.

Our best hope of a white one possibly from a Northwesterly direction.

Re long range models like Glosea etc.....sorry but I've lost all faith here. They couldn't be more off the mark and a lady with  crystal ball would do better. NONE predicted the end result for most of December which was a dominant Euro high retrogressing to Bartlett type.

I still think this Winter could be special just going on pure gut instinct. Here's hoping anyway

Well this isnt the gut instinct thread im afraid.

And looking at the ensembles (most of us dont live in Ireland!) it looks very dry, Not stormy and unsettled in the run up to xmas??

 

[knocker]

12 minutes ago, bluearmy said:

Wow - look at that monster cold Siberian ridge at day 7 on ecm

 

I must be having another senior moment as I'm struggling to find the monster ridge

[igloo]

2 minutes ago, January Snowstorm said:

It looks to me this evening that the models are firming up on a very unsettled and possibly stormy run up to Christmas.

Our best hope of a white one possibly from a Northwesterly direction.

Re long range models like Glosea etc.....sorry but I've lost all faith here. They couldn't be more off the mark and a lady with  crystal ball would do better. NONE predicted the end result for most of December which was a dominant Euro high retrogressing to Bartlett type.

I still think this Winter could be special just going on pure gut instinct. Here's hoping anyway

the billions of pounds it takes to run these longer term models i hope its not the tax payers money but it does look stormy over christmas lets hope we dont have a repeat of the boxing day storm of 1998

[feb1991blizzard]

Just now, knocker said:

I must be having another senior moment as I'm struggling to find the monster ridge

Monster Cold - 500dam heights with near 1040 surface pressure.

[knocker]

2 minutes ago, feb1991blizzard said:

Monster Cold - 500dam heights with near 1040 surface pressure.

My mistake as I applied 'monster' to ridge not cold. Pay attention!

[mb018538]

One word....yuck. Two 950mb lows and those horrid dark purples above that we don't want to see.

[frosty ground]

11 minutes ago, BLAST FROM THE PAST said:

Ecm looks like the worst run of winter to me.  

 

BFTP

Because......