Model Output Discussion 17th Dec.2013-12z onwards.

[bluearmy]

oh dear joe ...............................  

[Joe Levy]

oh dear joe ...............................  

What? Please explain to me my error rather than simply leaving me three words! I have been very busy this evening so I have barely had time to catch up with anything! 

Edited December 30, 2013 by Joe Levy

[bluearmy]

What?

 

havent you read the last couple of pages ................    you did make me laugh though

[gillybean]

What?

You mentioned the "s" word

[bluearmy]

Shame we can't see the ECM postage stamps at 240 hrs and 168 hrs but the 240 hrs ensemble spread is pretty interesting...

 

 

 

This suggests some members of the ensemble suite has similar or perhaps even more amplification than the operational.  Crumbs of comfort but still way out in FI...

 

i had a good look at the run mulzy and i wasnt sure if that spread is a depression cluster or a ridge. i fear the former (for coldies) which is why i posted that the favoured option (currently) would be for the jet to flatten any ridge.

[cooling climate]

You mentioned the "s" word

Do you mean snow. lol.

[lassie23]

You mentioned the "s" word

and it's not snow

[IDO]

What? Please explain to me my error rather than simply leaving me three words! I have been very busy this evening so I have barely had time to catch up with anything! 

 

I think what the Mods were getting at is that we are posting temperature charts at 10mb. A better chart would be Geopotential heights. This is the chart for the same time you posted:

 

 

This can then be correlated with the charts we use in the trop. Though I would agree the temp charts are far more dramatic!

[rich1974]

and it's not snow

And I'm shocked it's not the SNOW word, that's all that people on here seem to mention.

[A.J]

excuse me for butting in, just thought that I'd point out to all that this is the Model Output Discussion and nothing else.....if it's not model output then it's not for in here....how many times? 

[IDO]

The 18z GFS op is more amplified than the 12z, a possible trait of the pub run, but at T156:

 

Compared to the 12z at the same time:  

 

The better Alaskan ridge echoes downstream in respect to the Atlantic and Scandi ridges. May or may not benefit, but a good trend if maintained in subsequent runs.

[Cecil Hogmanay Melchett]

Early taste of spring for parts of southern Portugal and Spain next week,courtesy of that high stretching from the Azores to Slovakia,dragging up some very warm air from Africa!

[Allseasons-Si]

Not much to right home about the 18z,allthough there is slightly better ridging in the atlantic @168 + a bit more of a scandi ridge

 

18z

 

12z

 

 

[nick sussex]

The continuity over the Arctic is dismal between outputs, chunks of the PV flying all over the place! NOAA made some comments the other day regarding data collection around the Arctic oceans as being poor and we can see that here.

 

Upstream the GFS 18hrs holds the Canadian PV chunk further west earlier which is good but then you can see the differences between the ECM and GFS, the latter doesn't develop low pressure over the eastern USA there is no interaction between the PV chunk and energy moving up from the Gulf of Mexico, its crucial that we see a development here to help carve a more amplified ridge ahead, this also helps to deepen low pressure forcing it to track more ne towards the western side of Greenland.

 

The result is a Freddie Kruger special,  A Nightmare on Mild Street, dreadful stuff from the GFS!

Edited December 30, 2013 by nick sussex

[Purga]

18z pretty dire and unsettled in the extreme again right through into FI so far

The very cold airmass over Canada is going to continue the explosive cyclogenesis in the western Atlantic and keep the jet powered up

Some coldish uppers over the UK so it won't feel that mild but it also won't be wintry just wet & windy as usual.

 

Another storm battering for the end of the run

 

Phew...

Edited December 30, 2013 by Purga

[Jason M]

18z is truly awful. Zonal until march based on that run. Hopefully its wrong because some places are going to get some huge rainfall totals if this pattern persists for weeks on end.

[weather eater]

Lady's and gentlemen we give you the 18z and the zonal express, the weather phenomenon that just keeps giving.

[Cecil Hogmanay Melchett]

18z is truly awful. Zonal until march based on that run. Hopefully its wrong because some places are going to get some huge rainfall totals if this pattern persists for weeks on end.

Agreed jason

We really are well and truely stuck in a most hideous pattern and have been since late November.

I  just cant see a way out at the moment.

[JK1]

I must be only one that don't mind the 18z least it keep the proper cold away. though much prefer settled n mild. but anyways the amount of rainfall in places is serious.

Edited December 30, 2013 by JK1

[nick sussex]

Here are the respective ECM and GFS runs to show the huge difference upstream:

 

ECM 12hrs run 168hrs:

 

 

GFS 18hrs run 162hrs:

 

 

In the ECM that low deepens rapidly, its quite amplified so downstream you get a better ridge, then this low moves ne towards western Greenland, before this as the energy from the Gulf interacts with the PV chunk it helps to pull some of this away from Canada, now in the GFS there is no interaction, flat upstream so when the energy starts spilling east it just ambles along to Greenland and phases with low pressure near the UK, the ridge ahead is flat and it basically ends up in that mild horror show.

 

Even with the ECM its a close run thing because the troughing over the UK takes an age to weaken and elongate but you just about get to some interest.

 

Anyway lets just hope this is a rogue run because as we can see the models are making a pigs ear of the set up to the north, each output has a ridge here a PV chunk there and then this changes on the next output!

 

 

 

 

[Continental Climate]

18z pretty dire and unsettled in the extreme again right through into FI so far

The very cold airmass over Canada is going to continue the explosive cyclogenesis in the western Atlantic and keep the jet powered up

Some coldish uppers over the UK so it won't feel that mild but it also won't be wintry just wet & windy as usual.

 

Another storm battering for the end of the run

 

Phew...

Good lord that is one mighty vortex Chio et al weren't kidding when they said it would take some shifting. Looks like this winter is going to be a winter of thirds with the first two utterly zonal and trash. I will stick with my prediction of a couple of days ago nothing remotely cold and snowy until at least the 21st of Jan if were lucky

[shaky]

I have a feeling that by tomorrow evening the models will be showing that low pressure at 168 hours undercutting because of the scandi high out east!!it seems to me that throughout today that scandi high is getting slightly closer to us!!but then again I could be wrong!!goodnight all!!

[draztik]

I doubt many folk can be happy with our current pattern, but unfortunately it is what we have. And of course, it is always possible we will see a splitting of the circumpolar vortex, but looking at the recent GFS output - you would be hard pressed to bet on that happening, with or without this apparent Stratospheric warming indicated.

I have had a look at the extended ens from the ECM, and they aren't conducive to cold spell taking hold of our weather. EC32 will be out shortly, which will hopefully offer some direction.

 

EDIT : before I go to bed, ive had a quick look at the update. The EC32 is dire, staying zonal with mean troughing staying put towards our NW and into Greenland out to 22nd *the update is still rolling out so I cant go further*. Hopefully fergie or BA will offer a more extensive review.

Edited December 30, 2013 by draztik

[bluearmy]

Looking at the london ens gives us a better idea of clustering. Note that post the 8th jan, there are far fewer runs with precip and strong winds. The temps are generally below average. Looks like those anticyclonic members ian was talking about are gaining ground - and fast!

 

more of the same from the ec32. a bit more troughing into europe week 3 but in general, mobile w-e with low heights to the nw throughout.

Edited December 30, 2013 by bluearmy

[Bristawl Si]

Last third of January and into early February will see a dramatic change in our weather. Patience is the name of the game.