Model output discussions pm 31/12/15

[johnholmes]

The anomaly charts, that is NOAA 6-10 and to a lesser extent ECMWF show somewhat similar patterns and areas of +ve heights, see links below.

GFS not that keen so far. It does look more likely that some kind of cold shot is developing from north of west NOT east. The 8-14 shifts the fairrly marked trough over the UK with quite low 500mb heights, well smooths it out, but also shows the +ve heights extending close into the w/nw of Scotland with much lighter 500mb winds.

I would suggest a cold spell starting by day 6 but not clear how long or indeed what type it may be. Risk is over 75% I would suggest.

links below

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

this may be the 12z version of EC-GFS, not checked it, my comments were based on the 00z issue.

[Polar Maritime]

Certainly a more deeper/extended Northerly, With the jet further South on the 18z

 

Edited January 4, 2016 by Polar Maritime

[nick sussex]

I'm beginning to think the GFS and Paris Hilton are related, both attention seeking and useless! The GFS is all over the place, initially it backtracked towards the Euros with more amplification in the east Pacific and a more similar pattern then it hit the buffers and imploded.

I suppose one good thing is that we don't mind a bit of chaos as long as the models keep coming out with a cold solution!

Edited January 4, 2016 by nick sussex

[snowice]

6 minutes ago, BLAST FROM THE PAST said:

I think at this point the 18z is looking much better for sustained cold than 12z.  That ridge from Canada into N pole and the E seaboard set up has for me prolonged ridge from Greenland. No SW spoiler over Iceland

 

BFTP

look at the Hp over Greenland 1040mb moving slowly  south East.Tomorrow could be boom charts 

Edited January 4, 2016 by snowice

[Daniel*]

19 minutes ago, DAVID SNOW said:

'optimism' from our long standing experts on NW as well Dan!

Indeed David

We have experts oh we do, but the superiority in their data is of higher resolution than model output from the public domain by quite a stretch, which is fed back to us in videos, such as above that's why you can get a tad excited. Well done to GP (as well as Tamara) in particular whose been rather stern in uk cold potential. I have not felt this excited in a good time, best to not get too carried away. What the heck I've not had more than a inch since Jan 2013!

[damianslaw]

Firm agreement from the models this evening, all latching on to a significant pattern change by early next week - the change is the atlantic trough finally moving eastwards across the country allowing heights to build strongly to our west, the main force on what happens next comes courtesy of an arctic high.

Met office update alluding to the above, and quite rightly at this stage remaining cautious over the longevity of any change.

Ensembles consistent with ops as well, alongside NWP outputs.

At this stage its best to see things unfold, shortwave activity to the NW could end up being a spoiler but no reason to think this will happen given the positive signals for perhaps a more lengthy sustained colder period setting up shop.

By far the models today are the most convincing they have been so far this winter of a cold injection at long last..

For snow cold lovers, the models are certainly not offering up January blues, they've had 2 months of these already!

[Polar Maritime]

Please remember there are plenty of other threads for Media forecasts and banter, Please continue with sensible model discussion as to not clog up the thread.

Thanks, PM.

[karlos1983]

Can someone please tell me what an "in-proper Lexicon " is that Ian mentioned in his tweet? I don't think my phone has enough memory to have another tab opened for Google and I'm clearly thick 

[Singularity]

12z to 18z det. run comparison at +216:

Strong Azores High

Squashed Azores High.

 

The jet angles so much further south from the U.S. on this run, which is a consequence of there being no deep trough formation over Canada. Essentially another route entirely to the ECM, this one seeing areas of low pressure passing south of a cut-off high over Greenland.

It's a bit tricky getting sustained cold in the UK from that but you do get active lows engaging with cold air which can be fun. Needs that Scandi trough to ramp up a bit really - and dig further south.

[cyclonic happiness]

2 minutes ago, karlos1983 said:

Can someone please tell me what an "in-proper Lexicon " is that Ian mentioned in his tweet? I don't think my phone has enough memory to have another tab opened for Google and I'm clearly thick 

Irt means the wrong term was used, not 'snap' but......spell?

[weirpig]

2 minutes ago, karlos1983 said:

Can someone please tell me what an "in-proper Lexicon " is that Ian mentioned in his tweet? I don't think my phone has enough memory to have another tab opened for Google and I'm clearly thick 

think it means incorrect wording.

2 minutes ago, karlos1983 said:

 

 

[Ali1977]

Disappointing from day 8 but still looking ok, hopefully tomorrow is a ramping day...

[nick sussex]

2 minutes ago, karlos1983 said:

Can someone please tell me what an "in-proper Lexicon " is that Ian mentioned in his tweet? I don't think my phone has enough memory to have another tab opened for Google and I'm clearly thick

I think he meant to say improper basically he used the wrong language to describe things. The cold snap more likely to be a more marked change.

[ukpaul]

By 240h the 18z has reached a kind of stasis. It doesn't want to make any height rises but can't get progress apart anywhere else without it. Looks like a holding pattern run, no real direction at all to it.

[BLAST FROM THE PAST]

 

Hitting cold air....some places would get heavy snow  from this and mountains only.  As expected from earlier in run GHP keeping LPs on southerly track controlling Atlantic more

 

BFTP

[nick sussex]

Lets think back to last nights GFS 18hrs run. Does anyone remember the storm of the century that it forecast?

I think that says it all!

[BLAST FROM THE PAST]

5 minutes ago, nick sussex said:

Lets think back to last nights GFS 18hrs run. Does anyone remember the storm of the century that it forecast?

I think that says it all!

And the difference between 12 and 18z....although one must toy with the idea that it may take more than one hit/BITE to really flip the set up

 

BFTP

Edited January 4, 2016 by BLAST FROM THE PAST

[Singularity]

Typical that LP in the Atlantic goes from negatively tilted with disruption taking place (shortwave breaking away from SE corner) to a huge, well rounded feature in the space of 2 days once the det. run hits lower-res.

My advice to those about to take a look, just check it out to +240 and leave it there, for sanity's sake 

 

In fact, you may as well set the cut-off point at around +192 or even +168 given how crucial the upstream developments are at that time. Not only that, but for all we know, the UK-Scandi trough might dig further south at that time too, allowing cold air to the NE to get in on the act more.

There's another side to that as well I know - modifications in the wrong direction - but we all know those are there and it's more fun to write about the positive side 

[DAVID SNOW]

5 minutes ago, Earnest Easterly* said:

Indeed David

We have experts oh we do, but the superiority in their data is of higher resolution than model output from the public domain by quite a stretch, which is fed back to us in videos, such as above that's why you can get a tad excited. Well done to GP (as well as Tamara) in particular whose been rather stern in uk cold potential. I have not felt this excited in a good time, best to not get too carried away. What the heck I've not had more than a inch since Jan 2013!

Agreed Dan.

And its remarkable that some members here, at times,  get 'things' right , without the superiority of data that's at a higher resolution.

[BLAST FROM THE PAST]

1 minute ago, DAVID SNOW said:

Agreed Dan.

And its remarkable that some members here, at times,  get 'things' right , without the superiority of data that's at a higher resolution.

And it still not in the bag by any means yet......but we have movement in the right direction

 

BFTP

[tight isobar]

*like a broken record*

But I have to laugh at gfs consistency!  

Anyone fearing the current modeled 18zsuite is anywhere like where evolution will end up...Don't its modeled just about everything including the kitchen sink in the las 48hrs...

When hints at alignment with other output at times...

It'll all look different by this time again tomorrow. 

[DAVID SNOW]

1 minute ago, BLAST FROM THE PAST said:

And it still not in the bag by any means yet......but we have movement in the right direction

 

BFTP

"At times"

Hopefully Fred this is one of them

[feb1991blizzard]

11 minutes ago, nick sussex said:

Lets think back to last nights GFS 18hrs run. Does anyone remember the storm of the century that it forecast?

I think that says it all!

Yes Nick quite right, and after all was that worthy of a mention at such a range? (which it got plenty of), I'm sure people know what I'm getting at.

[ukpaul]

For fun, look at the Eastern Canada/US by 126h on the Panel GEFS (click on one then use the arrows), you may as well just throw a 20 sided dice!

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=126

Edited January 4, 2016 by ukpaul

[bobbydog]

lets not forget- whatever happens, the very confident "torpedo" forecast is not even within range of the models we get to see yet. anything in the meantime is a bonus.

the best is (potentially) yet to come....