Model output discussion - The Hunt For Cold

[ITSY]

6 minutes ago, Daniel Smith said:

The mean has stronger heights going up towards Greenland/Iceland compared with the 06z, I bet there's some incredible runs in there somewhere!

Just to ground us back to reality. There's still nothing to suggest widespread, significant snowfall at the moment, it'll turn colder sure, but it'll be surface cold for the most part from the initial Easterly, it's only really in the outter reliable that things start to get interesting! Though, I suspect that will slowly make its way out of fantasy land..

Just the 1040mb over Greenland, as a mean. that's a huge anomaly. 

[Tamara]

5 minutes ago, Steve Murr said:

however whats clear here (to me) is using the GSDM doesnt generate a forecast & at a more local level does little to forecast the type of change we will see in the next 10 days -

In your own words you do not believe that the tropics & associated teleconnective GSDM numericals indicate a change indeed the metrics above whilst up & down actually fit in a regular oscillation of normality... 

So, as you indicate - relative normality should remain in situ all be it perhaps         'slightly' orientated to weak amplification-

The coming circa 10 days are fully documented in the +ve momentum sequences and timelines as described in detail. In my own words, and not your incorrect interpretation, representation of them this translated to 'highly amplified' and not 'weak amplification'. The models are duly following an amplified pattern within the 10 day time period.

If you must dissect mine or anyone else post please do not put words into mouths. Thank you.

 

10 minutes ago, Steve Murr said:

he GSDM stand point is in your opinion nothing more than temporary amplification & no indication of patterns like the 80's yet in 5 days or so we are at a start point where the depth of Scandi high pressure is ~ 588 DAM circa 20 -24 Dam higher than any that can be found-

Is an amplification temporary taken in context of the period under the radar within my own post evolved? Its still late autumn for another two weeks. before winter proper begins

There is much one *could* reply wrt Ed Berry's presentation and your own interpretation of what you consider short-comings, but this is not the thread for it and I suspect you would not be interested anyway as your focus skews approaches you do not personally subscribe to as restricted to the attaining and sustaining of cold weather patterns.

However, the GSDM is created as an all year round diagnostic tool to supplement numerical modelling, not as a mechanism to fit signals/teleconnections into the desire for cold weather patterns 3 or 4 months in a year. I personally attempt to utilise these processes during the summer and adopt the same perspective as of today of fitting them to likely patterns and not preferred ones. Hence a pros and cons approach. Plus I do not pretend to be any self appointed clairvoyant forecaster anyway  - simply try to progress understanding and learning. And offer a differing perspective that hopes to avoid too much bias loading.

16 minutes ago, Steve Murr said:

Also post this nothing stands out in the GWO / MJO or indeed the GLAAM that supports high pressure retrograding to Iceland & edging to Greenland-

Orbit of the GWO through the Nino attractor phases does support retrograding to Iceland, Being a long post and only so much time and space to complete it, I omitted to state it and certainly accept that  could have been made clearer-

However, with that said and in support of the thrust I was emphasising - the focus was ultimately questioning what happens when the amplitude tropical forcing fades and angular momentum falls back. It seems you have chosen to omit that part to try to further discredit my post,

A fall back in angular momentum would imply some recovery in polar jet flow and a possible return to a more mid latitude pattern. Clearly the Scandinavian ridge has mileage to support a higher latitude pattern in the medium term, but again in that post I was, and still am, seeing this in perspective of it being late autumn still and not winter itself

This is the UK and not the tundra - putting aside the likes of 62/63 even the  coldest winters are not uniformly cold and allow for relaxation of the pattern, Unless you are suggesting this is the start of a protracted uninterrupted 3 month freeze?

Maybe you are suggesting just that, judging from your prophecy further down.

 

40 minutes ago, Steve Murr said:

I scoured your post and couldnt see any mention of ice anomaly - Yet this year saw the highest net polar temperature anomaly on record & the lowest every recover on record, adding to this the balance of ice in october being heavily weighted to the Canadian Side & record low anomalies over kara / Barents & laptev - this is creating a further dipole allowing for massive heat transfer North...

Yes I had already fully anticipated you would scour it before your post appeared. Some things can be wholly predicted ahead of time.

If I was making a 'formal' LRF (which I wasn't) and detailing every single forcing variable,(which wasn't the purpose of the post) I wouldn't have posted it in this thread. And momentum processes within the troposphere can be both augmented and detracted by unstable polar temperature and ice profiles.  Again not the thread for this debate.

Your own priority is to lead a charge for cold patterns and find reasons to support them both now and in the future. Different priorities, and also your own somewhat skewed (and incorrect) understanding and perspective of the GSDM, does not make the diagnostics wrong even if as a willing interpreter of the GSDM I am not bullet proof like anyone else when it comes to making forward suggestions based on them or any other method. Whether those are based on numerical models, or other approaches.

Maybe you might include yourself in that bracket as a mortal who can (and does) get things wrong as well?....

30 minutes ago, Steve Murr said:

This winter is going to be a decoupled winter Trop > Strat created by the heat transport driven by residual summer heat & ongoing ice loss -

 

30 minutes ago, Steve Murr said:

f you put all this together plus the suns weakness we stand on the cusp of a historic winter - which can forecast in advance - with little mention of the GSDM

.....Or perhaps not.

You are to be envied and possess a certainty of the future that surpasses anyone (professional or amateur and regardless of contributory approach) and so there is nothing left to discuss

And as stated previously, I'm heading back to my planet anyway

So just let it snow..

See some of you maybe next year

 

[shaky]

Heres to a good ecm this evening!!firstly i want that easterly further north and west then the low in the atlantic to slide further south at 144 hours!!should then be in for a cobra run!!easier said than done!!

[sorepaw1]

27 minutes ago, Paul said:

For those following the upcoming switch to colder weather, Nick's latest blog is well worth a read.

Colder Weather On The Way From The East Next Week, But Will It Snow?

Jo's video from earlier is also well worth a watch:

 

From that professional forecast 9c or

10 c. Next week  No snow mentioned 

Just low cloud and drizzle. 

Interesting view. 

 

Edited November 14, 2018 by sorepaw1

[Paul]

3 minutes ago, sorepaw1 said:

From that professional forecast 9c or

10 c. Next week  No snow mentioned 

Just low cloud and drizzle. 

Interesting view. 

 

Bearing in mind the forecast went as far as Monday/Tuesday, no further.

[Mike Poole]

The FV3 getting the cold aligned nicely towards the UK, here's the charts at T174:

Decent run again this, and if the high stays in that location, colder air still should result.

[bluearmy]

26 minutes ago, ITSY said:

Just the 1040mb over Greenland, as a mean. that's a huge anomaly. 

careful re slp over the Greenland plateau - z500 heights are what you need to look for over Greenland.

the main anomaly generally centred around Iceland  

[Man With Beard]

So we've had some slight movement from here to there in the past 24 hours but the main background facts have actually solidified - a strong block is v likely to form somewhere close to our north, strong enough to make the "will it snow" question a very reasonable one to ask. 

As ever with the UK, getting it to snow is not straight forward even with good background signals - so I think the answer to that question will belong firmly in the D5 or less range. 

I'm thinking it's a 30-40% chance that favoured areas will see snow by D15, but no sense in saying more than that atm. 

Finally, though I don't want to tread on any mods feet, could I suggest anyone who doesn't want to get into a snow related dispute, or doesn't like a post, head to the other thread. There's a lovely atmosphere in there and plenty of wise analysis. Let's not spoil this thread with arguments. 

Edited November 14, 2018 by Man With Beard

[feb1991blizzard]

What does GDSM stand for please?

[Laurence Hill]

1 minute ago, feb1991blizzard said:

What does GDSM stand for please?

Something something Steve Murr?

[feb1991blizzard]

I meant GSDM..

[coldie]

1 minute ago, feb1991blizzard said:

I meant GSDM..

Global Synoptic Dynamic Model

[Methuselah]

I think it's fairly obvious that most posters in here like snow as the thread is titled 'the hunt for cold'. But what is wrong with questioning the validity of others' predictions, whenever the 'inevitability' of Snowmageddon is brought into question? Surely the thread will be all the better for it...?

Anywho, there's more to teleconnections than relying solely on the JMO, James Madden Oscillation. Isn't there?

[winterof79]

Oh my days.....144z

Edited November 14, 2018 by winterof79

[The PIT]

Too early to get excited however again it could be a fairly split month with a sudden temperature change stopping it from being very mild and slapping it back down to average. All depends on whether we do actually drew in the cold over Europe or not and how long it lasts.

[Tim Bland]

Cold enough for some snow in the south east as early as Tuesday on tonight’s ECM and UKMO especially with a bit of height ...

 

[feb1991blizzard]

1 minute ago, winterof79 said:

Oh my days.....

Synoptically, its as good as it comes, notice the very slight curve in the isobars, in mid winter with a lower 500mb - 850mb profile, it would give a dumping even further North.

[ICE COLD]

Just now, That ECM said:

I think people are ready SM and Tamara’s post and are missing the ecm deliver as  a stunning set.

Heart in mouth moment mate lol . I’m looking at it rolling out but for some reason I can’t get it to update after T120

[ICE COLD]

T168 ECM . 

[Mike Poole]

Holy schmoley!  What on earth has the FV3 been on, is this the run of the decade?

T360:

Edited November 14, 2018 by Mike Poole

[bluearmy]

gfsp nh view late on ……….

[Always a red]

3 minutes ago, That ECM said:

I think people are reading SM and Tamara’s post and are missing the ecm deliver as  a stunning set. I think the two of you should have a pint and glass of vino and discuss, it’s like watching your mum and dad argue

Brilliant!

Come on peeps lets all chill, literally I hope!!!

[bluearmy]

not the best way of phasing the low heights on the 12z ec op …… suspect the remainder of the run could be questionable as this phasing is very specific

[Met4Cast]

2 minutes ago, Mike Poole said:

Holy schmoley!  What on earth has the FV3 been on, is this the run of the decade?

T360:

There's the Daily Express' snow bomb.. my word!!

[mulzy]

2 minutes ago, Mike Poole said:

Holy schmoley!  What on earth has the FV3 been on, is this the run of the decade?

T360:

Quite simply, one of the best runs we have seen in a long time!