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

[Weathizard]

1 minute ago, That ECM said:

T126 and that is a chart many would bank.

Anyone who wouldn't bank this chart as a starting point would have to be a lover of all things mild! Steady 12z so far.

[radiohead]

This run is reminding me a bit of the 18Z GFS last night, with the ridge a bit further west and looking like it may be about it get squeezed. Not sure I like where this is going, hopefully it turns out different....

 

 

 

[karlos1983]

Just now, radiohead said:

This run is reminding me a bit of the 18Z GFS last night, with the ridge a bit further west and looking like it may be about it get squeezed. Not sure I like where this is going, hopefully it turns out different....

 

 

 

Yeah I agree, It is a concern, Shortwave drama to thank for that appearing between Greenland and Iceland at around +90, hopefully it will change as frames go on.........

[Captain Shortwave]

Still we have disagreement at day 4

GFS

Low pressure over the Scottish borders, a cool cyclonic flow.

UKMO

Low pressure close to Norway with a north to north west flow with showers down coasts with the risk of more organised bands, of which these will be turning increasingly wintry from the north.

 

So the UKMO looks great, the GFS throughout really struggles to develop a proper cold flow. It must have been a bad day at the office  

Edited January 7, 2016 by Captain Shortwave

[radiohead]

Some interesting difference between UKMO and GFS at T96, both closer to home and nearer Greenland.

 

 

[SMU]

Meanwhile a stella start to the UKMO

perfect allignment for that low....

s

 

[Continental Climate]

If that low pressure to the north of scotland would just sink a few hundred miles we would be in a bitter easterly. I'm with radiohead with this though not a great run compared to some we have had. It is however one run and lets see where it sits in the ensembles. Onwards to the Euros which are more important anyway!!

Edited January 7, 2016 by Continental Climate

[Methuselah]

3 minutes ago, Weathizard said:

Anyone who wouldn't bank this chart as a starting point would have to be a lover of all things mild! Steady 12z so far.

I promise to bank that chart - when and if it ever materializes. So help me Ga'ad! How's that?

[Met4Cast]

No sign of the high getting squeezed, looks more robust to me, a little further West though which is making the low over Scotland a little slower to clear so the colder air not digging South quite as fast on this run. Other than that, the block is looking fine

 

 

[Geordiesnow]

14 minutes ago, mountain shadow said:

A chart with an explanation would help. No idea what your referring to.

The trigger low which will eventually move eastwards to release the cold air, between 72-120 hours, it barely moves as the GFS would appear to be correctly in predicting yesterday. The Euro's had this low moving quicker eastwards but this morning's runs have backtracked on this, especially the UKMO.

The affects of a slower trigger low is more rainfall during the weekend and perhaps even into Monday now, delays of the floodgates to the colder air, a larger milder sector(although the shortwave north of the Shetland Isles does not help) and more modified colder air as a result.

Not even on about the Azores low pressure system although the GFS 12Z run is hinting it may come into play on this run, the ridging is also a little bit further West but don't think its far enough westwards for a west based NAO though thankfully. 

Edit: UKMO 12Z 96 hour run is much better imo, the trigger low would appear to be well out of the way, therefore opening the floodgates earlier and I would imagine the uppers will be colder as a result. Hopefully the ECM will follow suit because it will at least if nothing else mean less rainfall than if the low was still slap bang over us. Then on a cold perspective, you should have a colder flow with less in the way of a mild sector. 

Edited January 7, 2016 by Geordiesnow

[bradymk]

Quite large differences here early on between UKMO and GFS. UKMO the better.

[karlos1983]

Nice from UKMO +120

Much cleaner than GFS

It's behaving and showing the trough over the UK the Door. Good riddance 

Edited January 7, 2016 by karlos1983

[Continental Climate]

Maybe an easterly in the making here? I agree with Steve looks better than the GFS. Could be a stella run from the UKMO here.

[terrier]

Not really liking the look of the gfs 12z the Azores low looks like coming into play and the cold gets delayed till Monday now on this run. Looks like the 18z last night. Think I will see what the ensembles say but I'm scratching my head wondering if the gfs has picked up a new signal. 

[SMU]

120 UKMO

much more solid northerly flow with embedded troughs

s

[January Snowstorm]

Indeed the gfs run is a complete mess and whilst it could deliver snow it doesn't lock in the cold

[karlos1983]

1 minute ago, terrier said:

Not really liking the look of the gfs 12z the Azores low looks like coming into play and the cold gets delayed till Monday now on this run. Looks like the 18z last night. Think I will see what the ensembles say but I'm scratching my head wondering if the gfs has picked up a new signal. 

I'm not sure the GFS is dealing with this setup at all well. even with it's 4 runs a day it's struggling to agree with itself. 

[radiohead]

The high is strengthening over Greenland on the GFS though. However it looks like quite a complex and maybe risky pattern. Quite different to the 06Z and the 12Z UKMO so, questionable for now.

[Captain Shortwave]

The GFS really does try and make this run as nerve wrecking as possible.

That said it just about makes it with a snow event around day 6/7 for the south.

It does look like the cold air will win on this occasion.

The UKMO is a cracker though out to day 5 and 6, no drama with that Azores low either.

One thing to note here is where the base of that ridge sits, the UKMO transfers this over the the ridge coming from north Africa, so now we have the situation where that Azores low could move north west and engage the upper trough moving out of Newfoundland, this could help drive the high further north in the days to come.

Still a lot to be resolved, and a lot of complexities to solve.

Edited January 7, 2016 by Captain Shortwave

[Daniel*]

00z

12z - Block much more robust, upgrade!

[Liam J]

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.

[Mair Snaw]

Just now, karlos1983 said:

I'm not sure the GFS is dealing with this setup at all well. even with it's 4 runs a day it's struggling to agree with itself. 

Brings back memories of Jan 2013 when the UKMO/ECM were much better with the pattern change... i seem to remember the GFS pick up the trend then went and had some major wobbles for a 24/48 period before coming back in line closer to the time... could it be upto its old tricks again??

[winterof79]

Very pleasing on the eye as Captain says

Edited January 7, 2016 by winterof79

[Great Plum]

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!

[Paul_1978]

1055mb high over Greenland at T+172; 1060mb at T+180. 

We havent had a GH like that for a long time. Little to be despondent about. These are not T+384 charts!!

 

Edited January 7, 2016 by Paul_1978