Model output discussion - mid-winter

[karlos1983]

2 minutes ago, Dancerwithwings said:

GFS 12Z....In the medium term...NEXTWEEK.....Temperatures are low, 850's low enough and pressure low...... SNOW 

What location is that for?

[I remember Atlantic 252]

5 minutes ago, Dancerwithwings said:

GFS 12Z....In the medium term...NEXTWEEK.....Temperatures are low, 850's low enough and pressure low...... SNOW 

Also my interest now appeared on 2 GFS runs, the runner timed for Wed night, we need it slightly further South, but an interesting one, could rival snowfest of 5th Jan '98

[nick sussex]

1 minute ago, feb1991blizzard said:

To be fair the GFS evolution wouldn't end in tears it would end in dumpings for huge swathes of the country including the South because if it went wrong then it wouldn't be the exact GFS evolution - pedantic I know

I’ve factored in the UKs luck that’s why it will end in tears ! 

I view cold synoptics with what can go wrong , how big or small a change does the evolution need to hit the buffers.

I can give you a list for the GFS 12 hrs, and they’re not big changes .

 

[feb1991blizzard]

Just now, nick sussex said:

I’ve factored in the UKs luck that’s why it will end in tears ! 

I view cold synoptics with what can go wrong , how big or small a change does the evolution need to hit the buffers.

I can give you a list for the GFS 12 hrs, and they’re not big changes .

 

No I know nick - I was joking - because of course if the exact run verified then it wouldn't go wrong but I know that's impossible!

[Chesil View]

 Fellow weather enthusiasts and posters if you are going to wait for perfect syoptics then you will always be disappointed and finding flys in the ointment. The GFS span sixteen days ahead for heavens sake. A lifetime in forecasting terms. Even in advance of Dec 2010 we had people saying this needs to be flatter or more amplified or uppers could be better for my locale. Just let it unfold. We could well be on the cusp of something special where just good enough is all you need rather than perfection.

[Dorsetbred]

9 minutes ago, karlos1983 said:

What location is that for?

According to the co-ordinates near Stow on the Wold..

[nick sussex]

2 minutes ago, Broadmayne blizzard said:

 Fellow weather enthusiasts and posters if you are going to wait for perfect syoptics then you will always be disappointed and finding flys in the ointment. The GFS span sixteen days ahead for heavens sake. A lifetime in forecasting terms. Even in advance of Dec 2010 we had people saying this needs to be flatter or more amplified or uppers could be better for my locale. Just let it unfold. We could well be on the cusp of something special where just good enough is all you need rather than perfection.

I’m not talking about way out into FI.

I don’t take anything past T240 hrs seriously , and my issue with the GFS is before day 7.

Yes we’re not looking for perfection but a good solid foundation. The GFS has dodgy foundations !

Lets hope the ECM can deliver a less stressful evolution.

Edited January 12, 2018 by nick sussex

[Dancerwithwings]

11 minutes ago, karlos1983 said:

What location is that for?

It's shows Midlands northwards....But at this stage it could be anywhere

7 minutes ago, I remember Atlantic 252 said:

Also my interest now appeared on 2 GFS runs, the runner timed for Wed night, we need it slightly further South, but an interesting one, could rival snowfest of 5th Jan '98

Still along way to go yet....Caution! not all have that slider as snow....COLD RAIN....Sorry for swearing

[BlackburnChris]

If anybody needs help finding there locations elevation this website tells you right down to your postcode www.routecalculator.co.uk/elevation

[Chevron12345]

1 hour ago, Steve Murr said:

pretty Decent 12Z our to about day 10-

If I lived in any of these locations I would be salivating at the models ( +150 M )

-Lake District

-Yorkshire dales

- western Pennines

- peak district

- Shropshire hills

- Exmoor

- Beacons & Snowdonia

- Sperrin in Ireland-

possibly even the Cotswolds - 

we could see DEEP snow accumulating from when the cold spell starts lasting 7-10 days... 

somewhere is going to get North of 30cm of snow from convective showers followed by frontal Atlantic sliders -

The most snowiest spell for the UK since 2010 ... let’s hope it’s backed up by the North Easterly Post 192....

S

Indeed - but the most uninhabited places in the UK. It always snows over the hills and mountains in winter! 

[chris55]

My summary of the output today,

 

Huge trough from the north west sets up to influence the UK (basically the PV ,or at least a huge lobe from it) bringing in a markedly cold north westerly with heavy snow showers to the north and west of the UK (though they could well penetrate further south and east) some areas seeing significant accumulations.

Then we have the potential runners developing to the south side of the trough, this brings the risk of some potentially stormy weather, but more importantly  if these runners develop favourably then some significant frontal snowfall could be on the cards for a larger area of the UK. We will will not be able to predict the exact track/intensity of these "runners" until much nearer the time but the risk of snowfall is high imo.

Then following that, we have the prospect of the trough (over the UK) digging south and east into Europe, this will open the door to CAA on the top side, and with the Azores ridge following behind and pressure rising in its wake there is the prospect of quite a lengthy northeasterly/easerly flow to develop as we head into the longer term.

 

Overall a very wintry outlook!

And zero signs of the predominant January pattern of recent winters where the dreaded Barlette has set up shop (in fact we have hardy had a whiff of a barlette this winter thus far  )

 

[snowice]

Ecm looks fine at 96 cold uppers pushing south

Edited January 12, 2018 by snowice

[karlos1983]

Here’s the runner at 120 on the big 3.

I would say the UKMO develops it the least, but not a huge difference.

Edited January 12, 2018 by karlos1983

[nick sussex]

The differences upstream are in relation to the handling of Pacific shortwave energy and whether that phases with shortwave energy moving east across the central east USA.

You want phasing at T144hrs , the GFS fails to phase and this means the Pacific sourced shortwave heads towards sw Greenland as a separate entity.

Edited January 12, 2018 by nick sussex

[nick sussex]

The ECM has completed the phase of energies . Amen to that ! 

This is key as it effects how quickly upstream energy will move east. 

If the GEFS have too many non phased outcomes then if it’s wrong with that you can chuck them in the bin.

However until we know what will verify upstream it’s a case of wait and see I’m afraid .

Edited January 12, 2018 by nick sussex

[karyo]

Some relief from the 144 hour ECM chart as the runner is not developed much and is further south than the gfs.

Also, the Azores high seems ready to ridge northwards

[chionomaniac]

Please stick to the models. The will it snow chat at Xm asl chat can be put in the regionals. Thanks. Anything along those lines will disappear quicker than the snow will melt at sea level...

[chris55]

The runner runs.... this feature will be one to watch re potential snowfall. Way to far out for detailed analysis though.

[shaky]

Fantastic ecm so far!!ridge morthward into greenland and shortwave at 120 hours further south!!

[snowice]

Ecm 144 very similar to UKmo. 

[bluearmy]

Ec brings the runner in just south of Ireland and exits off the Sussex coast 

it’s quite a tight feature and doesn’t produce a large amount of snowfall - s welsh hills and South Downs most 

this will not be the actual track though 

[Ice Day]

Good consistency between the ECM's 0z v 12z out to 168.  If it could end in the same way as this mornings, it would get the weekend off to a cracking start.

 

 

[BlakeyWeather]

6 minutes ago, iand61 said:

Sorry but at a thousand feet up in the Pennines, I had to pay a rare visit into the model thread.

i’ll get my coat 

How's the weather down there mate?

NH view on ECM at 168 shows the low slowly sinking south towards the UK with some fairly cold air embedded.

[Chesil View]

40 minutes ago, nick sussex said:

I’m not talking about way out into FI.

I don’t take anything past T240 hrs seriously , and my issue with the GFS is before day 7.

Yes we’re not looking for perfection but a good solid foundation. The GFS has dodgy foundations !

Lets hope the ECM can deliver a less stressful evolution.

HI Nick certainly in no way digging at your good self.

Good foundations I would agree are a prerequisite especial UK snow wise

[terrier]

well for those looking at the gfs and ecm snow accumulations charts then looking at this I would say there are very much overplaying the depths.