Model Output Discussion - 05/01/2016 18z onwards

[Continental Climate]

Bit of a nor easter setting up? Pretty good chart though. Not sure the Arctic high is as strong as it has been on previous runs though. That's nit picking though every one of us would have took this with glee three weeks ago 

[karlos1983]

1 minute ago, *Sub*Zero* said:

GFS a right mess, out to Friday now and whilst it would be cold the deep cold still hasn't landed over the UK, apart from the N Isles.

and it wants to raise heights over Spain/S France. It's a mess.

Edited January 7, 2016 by karlos1983

[Geordiesnow]

The UKMO has backtracked AGAIN into what it was showing yesterday, trigger low further East, flood gates to colder air comes sooner and its a cleaner flow  and the risk of any Azores low is diminished also.  

The GFS is its usual messiness however I'll wait and see on the ECM run before getting carried away about the forecast of the trigger low which releases the cold air. 

[January Snowstorm]

I personally don't like the ukmo at 144 hrs. No proper ridging into Greenland more an atlantic hig

[bradymk]

GFS isn't an awful run. It is cold. It's just not as good as UKMO in getting the cold as south as quickly and does look more risky. Again, its just not consistent from the GFS and it will change again by the next one. Great last UKMO chart, we await the ENS and ECM.....

[Froze were the Days]

GFS - bloody azores low! becoming far more of a feature and Greenie high less so - something to keep an eye on!

[winterof79]

1 minute ago, Great Plum said:

The GFS is a bizarre run so far with little low pressures meandering around the British Isles... However, whilst it does this, the upper air still gets colder - meaning by this time next week, we have this little feature - with -5 air over virtually the whole country, it could be snowy...

(T

 

(this is conjecture of course - it will change the next run...) what we can say with confidence now, is that it will turn increasingly colder throughout the week!

Agree with the getting colder,and if GFS has it correct meandering lows are renown for dumping streamers from all angles in previous years when our cold pool has evolved 

[Liam J]

1 minute ago, January Snowstorm said:

I personally don't like the ukmo at 144 hrs. No proper ridging into Greenland more an atlantic hig

My concern as well, Heights lowering over Greenland throughout the run... Where would it go from T144? 

[ALL ABOARD]

 

Not as quick at getting the cold in but surely people must be happy with this chart i.e long term for cold. The heights across Greenland just build and build!! No easy way back to warm from there imo!!

[Continental Climate]

Just now, *Sub*Zero* said:

My concern as well, Heights lowering over Greenland throughout the run... Where would it go from T144? 

Yes if you look at all three charts in quick succession it seems it could be toppler territory at 168. Hope not though!!

[radiohead]

Greenland High continues to grow stronger in FI on the GFS, though high pressure is pushing in from the southwest towards us. That Azores low needs careful watching.

[MKN]

To my untrained eye heights to the north of greenland arent anywhere near as favourable to sustain the high pressure in the mid atlantic on the UKMO wereas the GFS has a very solid looking greenland high. There for id av thought the GFS would be best outcome if you are looking for a longer cold spell.

[Geordiesnow]

2 minutes ago, January Snowstorm said:

I personally don't like the ukmo at 144 hrs. No proper ridging into Greenland more an atlantic hig

I'm always wary when it comes to Greenland highs, I see it time and time again where the models hint at it only for the ridging never to fully make it seems however that said, the UKMO is a superb run and its a lot better than this morning's run regarding the cold for the UK and I actually don't mind that 144 hour chart but I can see why you may not like it though. 

Would like more consistency in the UKMO output and see what the ECM has to make of it all, especially with how quick the cold air arrives. 

[rory o gorman]

 

1 minute ago, Continental Climate said:

Yes if you look at all three charts in quick succession it seems it could be toppler territory at 168. Hope not though!!

How does one topple a cut off greenland high ?

[Woollymummy]

warm air advection...warm air moving into a colder region, like what will hopefully happen when the Atlantic ridge of high-pressure warm air is squeezed up towards the arctic....

Edited January 7, 2016 by Woollymummy

[Liam J]

GFS while worse earlier on it turns into a very good run with heights pumping up over Greenland... All FI for now.

 

[karlos1983]

1 minute ago, SnowTornado said:

To my untrained eye heights to the north of greenland arent anywhere near as favourable to sustain the high pressure in the mid atlantic on the UKMO wereas the GFS has a very solid looking greenland high. There for id av thought the GFS would be best outcome if you are looking for a longer cold spell.

I would much rather take a middle ground of the two to be honest, which stops the High sinking and stops the Cold from being pushed to far north as heights lower in the Atlantic and potentially put us in a westerly airflow.

[Harsh Climate]

lol at people getting upset over the gfs 12z, imo its another fantastic run! It shows a strong greenland high, whilst that is in play I only see a cold/possibly snowy outlook. Rather than looking for specifics off a single poxy gfs run lets look at the bigger picture, a blocked atlantic and a big greenland high, doesn't get much better than that! Like I said yesterday, every gfs operational run that rolls out is only one of many solutions (one of 15 perpetrations if you will), esembles are what will be significant.

 

And UKMO 12z is still very good

 

Edited January 7, 2016 by Harsh Climate

[Continental Climate]

1 minute ago, rory o gorman said:

 

How does one topple a cut off greenland high ?

UKMO isn't a cut off Greenland high

[karlos1983]

GEM looking good, heights across the pole 

Edited January 7, 2016 by karlos1983

[Geordiesnow]

One last post from me but for me, I rather the cold come in quicker than worrying when it might end and the UKMO does that, the GFS just faffs on with that trigger low, it takes ages for cold air to come and when it does, its fairly modified. 

One thing against the UKMO potentially is what people have pointed out is that it does not seem to sustain heights into Greenland as well as previous runs so the UKMO may not be the best for the longer term but in terms of getting the cold in and in terms of snowfall, the UKMO is the better run imo and I would bank that run over the GFS run for sure. 

[Nick F]

16 minutes ago, Greenland1080 said:

Lovely ukmo120

 

UKMO global a lot 'smoother' and quicker transition to a northerly Am flow, though not sure whether this could be the lower resolution not picking up secondary lows down the western flank like GFS high res  ( I prefer to use secondary low rather than shortwave which IMO be used for an upper trough). 

UKMO appears to move the long wave upper trough and south moving jet on western flank further east than GFS  by t+144 - which goes some way to explaining the quicker route to cold Am air.

Edited January 7, 2016 by Nick F

[Froze were the Days]

GFS isn't a good run...that small azores low turns into a major feature and most of the really cold air is kept to the north of the UK and find it difficult to see how any 'decent' cold air can get to most of the UK. No WAA on this run (in the middle stages) due to this...just hoping that the ecm doesn't follow suit.

Edited January 7, 2016 by Froze were the Days

[Ali1977]

This really could be a prolonged, as in several weeks of interesting model watching, with lots of cold weather...GFS hasn't quite got to grips with it, changing between each run quite a bit...interesting ECM to come later!!

[Daniel*]

2 minutes ago, *Sub*Zero* said:

GFS while worse earlier on it turns into a very good run with heights pumping up over Greenland... All FI for now.

 

I do not think so heights building to S not what we want, I'd definitely take UKMO that block seems sufficient. Although the longevity of cold may be somewhat reduced.