Model Output Discussions 06z 04/11/16

[Seasonality]

1 minute ago, warrenb said:

I have been reading models for a long time, and at no point alluded to it being a bad things, just discussing what the models are showing.

I believe that we shall have a west based -NAO but this will propagate East as time goes on. 

No offence intended, but I'm surprised at a west based NAO being discussed as a certainty, not nailed on yet.

[Ali1977]

3 minutes ago, Seasonality said:

No offence intended, but I'm surprised at a west based NAO being discussed as a certainty, not nailed on yet.

With you on this, the block is looking more likely now (Still not ECM though which should be noted), but given FI is only a handful of days away to say we are getting a WB -NAO is a bit presumptuous.

It's a case a one run at a time at the minute, and hopefully we start getting multi model consistency in the short to medium term which can then shed some light beyond.

[Grimers]

The GFS model shows windy conditions for SW parts of the UK tomorrow.

Edited November 16, 2016 by Grimers

[Paul]

For those following the models and the global drivers in the run up to the start of winter, Nick's latest blog is well worth a read:

Weak Polar Vortex To Bring A Cold Start To Winter?

[phil nw.]

Greenland and Canada is where the Gefs surface pressure graphs show rises for the rest of November.

Greenland on the left

As expected some spread in the members further on but the trend upwards pretty soon is clear.

That's always the first step to a cold pattern in the UK-getting and maintaining Arctic heights,that and the lower pressure to our south along with jet.

Currently the southerly based Russian block is poorly positioned though drawing milder air north into parts of Europe.Cut off low pressure over W.Europe is modeled later but any easterly is unable to bring any cold air west whilst that stays.

Day 7 mean chart

 

Later frames in the gefs show that it does fade and as the pattern evolves Siberian troughing develops and starts to advect the cold south and west towards Europe.That's usually what happens provided we see sufficient Greenland heights hold for long enough.

Of course that's me speculating on what would happen if all the pieces in the Polar profile fall the way cold lovers want.For the time being it's watch and wait but it's good that we are at least in the position of watching a pv struggling heading into Winter-it doesn't happen too often and makes for fascinating chart viewing.

[Geordiesnow]

Think its way too early to be thinking about west based NAO when we may not even get a Greenland high forming at all, its certainly a possibility but so is anything really. Do hope we continue too see the trends of the Russian high becoming less of a player over Scandi and we see some of the PV drop into Scandi but that could well take a while as you I do get the feeling the Russian high could becomes a nuisence and hang around for longer.

In particular interested what the ECM will throw up, especially regarding Sunday's low, it was the first model to pick up on this but this morning run has decreased the intensity of the low which will probably be nearer the mark.

[Ravelin]

West based -NAO, anyone remember the output we were looking at only 3 days ago?

FI is FI whether it's showing a possible west based -NAO, or a raging blizzard with snow half way up my door.

Anyway, all eyes down for the GFS 12z which is rolling out now, will it shed any more light on what happens after the coming weekend?

[bluearmy]

17 minutes ago, Ravelin said:

West based -NAO, anyone remember the output we were looking at only 3 days ago?

FI is FI whether it's showing a possible west based -NAO, or a raging blizzard with snow half way up my door.

Anyway, all eyes down for the GFS 12z which is rolling out now, will it shed any more light on what happens after the coming weekend?

I'm not responding to fi op runs - I'm looking at the gefs mean/anomolys and spreads - it's only noise at the moment.

[Mucka]

5 hours ago, bluearmy said:

all eyes on heights to our south re west based -NAO and its potential effect o the UK. if heights are low to our south then I wouldn't be too concerned unless its an extreme west based solution and even then, low heights to our south in winter pretty well guarantees a cold surface for the UK 

 I was just looking through the forum for someone who mentioned this.

The 06z suite was certainly very West based -NAO through FI with all our lovely heights being sucked West into Canada allowing the Atlantic back in.

Of course the jet will have been forced well south so so in theory it could allow for a freakish true cold zonal flow with LP running to our South even without obvious positive height anomalies to our N/NW should it set up that way, especially as the PV is expected to be so weak, as well as the possibility of the jet returning North.

Just musing aloud, all conjecture, we really could get anything through early Dec. I would much prefer a stonking cut-off Greenland high to be modeled as that is a pretty secure route to a very cold NE flow.

Edited November 16, 2016 by Mucka

[Ali1977]

Better WAA again by 114, last 2 runs have done this which is a good sign. Still not sure where it will lead but will surely help with blocking to our North.

[Weathizard]

Honestly the Russian high pressure systems irritate the hell out of me, maybe it's just me but they always seem to set up in the least favourable way possible.

That being said I feel we are at a pretty decent starting point with building blocks in place for potential down the line, just can't see anything this side of December.

[Ravelin]

1 minute ago, Ali1977 said:

Better WAA again by 114, last 2 runs have done this which is a good sign. Still not sure where it will lead but will surely help with blocking to our North.

Was just going to post this...

6Z   12Z

[Mucka]

5 minutes ago, Weathizard said:

Honestly the Russian high pressure systems irritate the hell out of me, maybe it's just me but they always seem to set up in the least favourable way possible.

That being said I feel we are at a pretty decent starting point with building blocks in place for potential down the line, just can't see anything this side of December.

LOL I think you will get some support from nick for that view. What it is good for is stalling the trough which helps prevent our Atlantic ridge becoming an ordinary toppler (hopefully)

We can see that GFS runs shortwaves though the top of the ridge just SW of Greenland, it just makes less of them than ECM.

Beauty this afternoon. WAA well into Greenland

 

Edited November 16, 2016 by Mucka

[Daniel*]

This is looking good the ridge well aligned to Greenland definitely less west based.

[Paul_1978]

1 minute ago, Changing Skies said:

This is looking good the ridge well aligned to Greenland definitely less west based.

We would have sold our grannies for a chart like that at T+132 last winter. 

[Mucka]

UKMO not such good news

Edited November 16, 2016 by Mucka

[Spah1]

Cohen

"Season of superlatives looks to continue. Have to believe GFS can't miss wind reversal by this magnitude but take nothing for granted"

 

[tight isobar]

Polar energy at Russian peninsula'(kamchatka) is further aiding development' via weaknesses in vortex...

Will aid spillage of polar air nw Europe'and deeper south trajectory. 

[feb1991blizzard]

9 minutes ago, Changing Skies said:

This is looking good the ridge well aligned to Greenland definitely less west based.

Yes, look at the flow to the NW of Scotland around 144, its more NE to SW as opposed to E to W than the last run which is a classic signature of west based -NAO, its not perfect, we would want it just blasting as a N'ly right down to S England before any E component but its better.

Edited November 16, 2016 by feb1991blizzard

[Ali1977]

11 minutes ago, Mucka said:

UKMO not such good news

Which makes you wonder if it's worth looking beyond 144!!!  GEM also similar to the UKMO.

Edited November 16, 2016 by Ali1977

[Geordiesnow]

Think the GFS has lost it way a little bit on this run and the detail is messy but it goes to show once you get a Russian high in place, they are mighty hard to shift and when they are in the wrong orientation, its even more annoying. You get a Greenland high on this run but no real cold, you just got to laugh really!

UKMO does not really go for a GL high but at least its seems keen to drop heights quicker than the GFS. Still feels any real noteworthy cold shot is a long way from forming whichever way you look at it but all interesting nonetheless.

It also makes much less of that storm than the GFS which is back to normality really of GFS overdeepening the lows and the UKMO looking dull as per usual.

[Daniel*]

8 minutes ago, Paul_1978 said:

We would have sold our grannies for a chart like that at T+132 last winter. 

Indeed

Could we be seeing a bridge of +ve heights? Stretching from Scandi to Greenland.  

[Ravelin]

4 minutes ago, Changing Skies said:

Indeed

Could we be seeing a bridge of +ve heights? Stretching from Scandi to Greenland.  

It's trying

[igloo]

10 minutes ago, Ali1977 said:

Which makes you wonder if it's worth looking beyond 144!!! 

it makes you wonder is its even worth viewing the GFS in the first place unless the the UKMO and ECM show the same thing which they dont its likely another example of its faults and there has been many over the past 10 years of model watching

Edited November 16, 2016 by igloo

[nick sussex]

The GFS 12hrs run upto T192hrs is an example of how to have one of those 5 star ingredients being high pressure over southern Greenland and Iceland but still end up with zip in terms of interest. Please someone nuke that Russian high, its impossible to advect any proper cold into Europe with that limpet hanging around. Of course if the Russian high was orientated in a way to advect some cold then you can be sure it would give up the ghost quickly.

 

Edited November 16, 2016 by nick sussex