Model Output Discussion 1st January 2014-06z onwards.

[Cecil Hogmanay Melchett]

GFS06Z at 114h is a perfect example of the pattern from hell.

At face value you really would have to say its a long long way to cold from there with a huge Euro high covering much of the mainland and a very strong jet stream coming out of North America.

[Polar Maritime]

And where is the cold going to come from, pattern change seems likely in my view post days 9-12 but not a profound one, at least that's where the background signals appear to pointing at the moment, I see very little signal for a change to significant cold followed by snow.

 

As i  said W.E change to cold Zonal ie N/W flow not West. Not significant cold or snow, it's a start.

[Cecil Hogmanay Melchett]

This run looks better, WAA into Greenland looks stronger .

If we didn't have the immovable slug AKA Euro high i would tend to agree,the upstream pattern is certainly an improvement with a developing -AO.

The problem is the trough near the UK will just fill and move NE leaving us in no-mans land thanks to that slug.

Temps of 8,9 or even 10 degrees across parts of Germany  Poland and even western ukraine by the 8th of Jan,thats got to be 6 or 7 degrees above the norm,staggering.

Edited January 2, 2014 by Cecil Hogmanay Melchett

[OldMetMan]

Morning folks, and a Happy New Year to you all.

Although we are still very much in the throes of a relentless Atlantic progressive flow, a couple of things in recent runs of both the GFS and ECM have caught my attention. But first, today, I notice that we once again have a small 500mb high stationed near Iceland. Admittedly, it's a weak affair, but I think it has significance:

The persistent upper vortex responsible for this prolonged unsettled spell, and the many shortwave features running around it, seems to be displacing further S, along with a gradual shift of the jet likewise.

The feature on the model runs I mentioned is the intermittent appearance of HP near Scandinavia, plus in recent GFS runs, cold air has been getting dragged S to the NE of Scandinavia. There has been signs of a weakening in the flow late in the period too, which suggests an opportunity soon for finally some northerly blocking to set itself up.

I think the remarkable strength of the jet these past weeks has precluded any possibility of this, even keeping the European HP well SE, but in my experience, these hyper-active phases can only ever last a limited time, before they fizzle out and I suspect that time is soon. The temperature gradient across the US is evening out a bit more which also suggests a weakening flow.

As an aside, the stratospheric thread is rife with speculation, based largely on model output, of a sudden warming arriving, which if it happens, could have major implications for blocking and Atlantic flow reduction, but it's by no means a done deal.

However, for now, looking at regular tropospheric model output, there is definitely a changing trend to quieter conditions later this month, and if the GFS continues to show cold air pooling to our NE, maybe some blocking and cold E/NE winds, once this jet burns itself out and the Atlantic vortex finally disrupts and moves away.

If such a trend is real, then I would expect the model output to pick it up more consistently over the coming days - we'll see!

[draztik]

You can put lipstick on a pig... But yeah, the models this morning have taken a big step backwards imo - from an already poor outlook. We have the NAO fluctuating between neutral and positive from the ens, with the AO showing signs of edging back into positive territory. So that's the teleconnections moving in the wrong direction.

The height anomalies from the extended ecm ens, highlight the problem for the UK in terms of synoptics. Mean trough stubborn to move from the NW. With lower heights over Greenland and into Scandi.

Day 7-12 height anomalies

And notice the euro high? Naefs 0z, broadly inline with the ext ecm, with lower heights to our nw, while eastern Europe sees a fairly positive height anomaly, which translates into fairly mild conditions for most of Europe. Incredibly so, looking at eastern Europe and up into areas of eastern Scandinavia. (day 11-15 height and temp anomaly below)

The mean temp anomaly indicated by GEFS 0z is also reflective of this euro high, with most of Europe in positive, while the UK looks average at best, slightly below in some regions.

Days 8-16 temp anomaly GEFS mean

[shedhead]

Excellent post Draztik, sums things up very nicely, if rather depressingly!

 

Can I ask for a link to your final temp anom charts?

[Cecil Hogmanay Melchett]

You can put lipstick on a pig... But yeah, the models this morning have taken a big step backwards imo - from an already poor outlook. We have the NAO fluctuating between neutral and positive from the ens, with the AO showing signs of edging back into positive territory. So that's the teleconnections moving in the wrong direction.

The height anomalies from the extended ecm ens, highlight the problem for the UK in terms of synoptics. Mean trough stubborn to move from the NW. With lower heights over Greenland and into Scandi.

Day 7-12 height anomalies

And notice the euro high? Naefs 0z, broadly inline with the ext ecm, with lower heights to our nw, while eastern Europe sees a fairly positive height anomaly, which translates into fairly mild conditions for most of Europe. Incredibly so, looking at eastern Europe and up into areas of eastern Scandinavia. (day 11-15 height and temp anomaly below)

The mean temp anomaly indicated by GEFS 0z is also reflective of this euro high, with most of Europe in positive, while the UK looks average at best, slightly below in some regions.

Days 8-16 temp anomaly GEFS mean

A very sobering post and the temp anomoly for Europe out to the 18th of January is staggering.Positive anomalies virtually everywhere you look aside from Iceland and Greenland.Always a tell tale giveaway sign of a +AO/NAO.

Edited January 2, 2014 by Cecil Hogmanay Melchett

[cooling climate]

At t144 on the GFS 06z run this is where we would like to have strong wave 2 activity which would

build heights to our north as per Nick Sussex post earlier. Unfortunately without this the energy and

lows to the nw will move east flattening the pattern as we have seen so often this winter.

With wave 2 amplitude forecast to become much stronger during the second half of January we

would be  likely to see a different outcome should similar synoptics arise.

[shedhead]

A very sobering post and the temp anomoly for Europe out to the 18th of January is staggering.Positive anomalies virtually everywhere you look aside from Iceland and Greenland.Always a tell tale giveaway sign of a +AO/NAO.

Indeed CHM, the lack or Eurasian snow cover is already a concern and if things pan out as progged we may not have much low level snow lying west of the Urals come mid month!!  Clearly the continent will cool down considerably quicker once we change the airmass, but any initial Beasterly is likely to be more gums than teeth...

[Frosty.]

Not sure if anyone has mentioned the GEM 00z this morning..so I will,  it has a lot of potential for coldies with high pressure ridging south from iceland, a scandi trough, atlantic lows further southwest with slider / undercut possibilities and generally it has a proper wintry January look about it beyond T+168 hours, especially for the north with a higher snow & ice risk..I would Bank this Gem run..it screams potential. I am firmly of the opinion that we are heading for a colder outlook, be it cold zonal / arctic / with trough disruption and southerly tracking jet or via high pressure building to the east/se with an increasingly cold continental flow, I can see the current stormy spell gradually running out of steam during the next seven days or so but that doesn't mean we won't have continued low pressure domination and in the meantime there are more disruptive spells, during the next few days and then again early next week.

Edited January 2, 2014 by Frosty.

[mountain shadow]

You know we're struggling for cold charts when Frosty is having to dig out charts from the GEM!

Sadly, we are now looking towards late January for anything prolonged cold wise.

[Frosty.]

You know we're struggling for cold charts when Frosty is having to dig out charts from the GEM!

Sadly, we are now looking towards late January for anything prolonged cold wise.

I think the Gem is a good model, no matter what it shows, I have used it a lot in the past and it's right up there with the best / worst of them.

[shedhead]

You know we're struggling for cold charts when Frosty is having to dig out charts from the GEM!

Sadly, we are now looking towards late January for anything prolonged cold wise.

It does look very poor to be fair. Can't remember the last time I saw the -5c 850Hpa line pushed a 1000 miles east of Moscow in the depths of Winter, but I'm sure the locals love it given what they normally have to face..

 

 

Contrast our dire outlook to this blasting down across the Eastern US early next week...-10c 850Hpa line approaching N Florida!!

 

Edited January 2, 2014 by shedhead

[legritter]

Indeed CHM, the lack or Eurasian snow cover is already a concern and if things pan out as progged we may not have much low level snow lying west of the Urals come mid month!!  Clearly the continent will cool down considerably quicker once we change the airmass, but any initial Beasterly is likely to be more gums than teeth...My ex mother inlaw was all gums but boy could she bite . as far as weather Models the zonal train continues but some signs on horizon of a cooling down eventually .just a hunch but i think this afternoons GFS could give us some cheer after 268 hrs as pressure possibly rises out east ,fingers crossed ,cheers all .

[The PIT]

A poor 06oz GFS and the mostly mild outlook set to continue even into FI. Normal deep FI tease is there of course. The only good sign is the jet is getting more amplified however everything is still in the wrong place for a proper cold blast.

[shaky]

Potential snow event for this weekend should hopefully come in range of the nae later on this evening!!!might aswell talk about that than the depression of talking about whats going to happen in about 2 weeks time!pretty certain fergie will shed more light on this POTENTIAL event later on!!

Edited January 2, 2014 by shaky

[Summer Sun]

Excellent post Draztik, sums things up very nicely, if rather depressingly!

 

Can I ask for a link to your final temp anom charts?

 

You can get it here but you have to pay

[shedhead]

You can get it here but you have to pay

Tks a lot SS.

[snowmadchrisuk]

Looking at current output we "COULD" be in an Easterly flow in a couple of weeks, sign of the the main PV chunk becoming weak and moving West , why at the same time them NE Heights look moving West also in the pattern , would only need about 300 miles further West on current models to have the Uk in a continental flow, wouldn't be cold at first as Europe isn't cold , but 48-72 hour's after setting in the uppers would flood South ...  really do think were on the way to a big pattern change soon ... 

[nick sussex]

The GFS 06hrs run continues to further amplify the upstream pattern, can we squeeze a bit more out of this trend?

 

Amongst the rather downbeat tone in here and the rush to order the prozac in some positive changes seem to have gone under the radar, of course we don't see the outputs bringing in anything colder but to presume everything we've seen this morning is going to remain as is seems somewhat strange!

 

So heres the last 3 GFS runs starting from last nights 18hrs run to T156hrs:

 

 

Then the 00hrs run to 150hrs:

 

 

Then the 06hrs run to 144hrs:

 

 

So in the space of 18hrs there has been a stronger high to the ne and the upstream pattern has become more amplified with a sharper dig of the PV to the west.

 

Will that be the end of the changes, we still have problems with the limpet troughing and of course nothing might come of this but I'd just urge a little delay in people calling the outlook until we see whether theres any further improvements upstream, bear in mind that if the upstream pattern further amplifies then even with some phase we might still be able to clear that piece of energy.

 

Also factor in problems with data collection in the Arctic oceans area, this was commented on by NOAA, will the ridge to the ne be stronger or is it being overplayed?

 

Overall the outputs still favour a close but no cigar outcome IF what we see today is what actually verifies!

 

 

[lassie23]

We really need a big change in the weather in North America and Canada. As long as that intense cold keeps pouring into the Atlantic, then we are screwed.

[bluearmy]

assuming the extended ens are in the right area (and so far this winter, they have been, there is no reason to think that proper cold winter will be paying us a visit for at least the next fortnight and possibly a week thereafter. the only straw for coldies is the 00z ops. of course, this could be the point where the ops make the running and the ens become unreliable but i see no reason to think that this is now. the split that was evident last couple days seems to have drained away somewhat towards the west flow being renewed after a couple of coolish days.it appears to me that our cold chances lie with whatever may transpire high up. the next ec32 due out tonight so we'll see if the control goes blocky again later in jan.

[carinthian]

OK . this is the latest. In the fields of high-resolution variations models, a portal internet service provides short and medium range predictions for snowfall and in -house longer term forecast . Current calulations are for the period 10-24 th January 2014 and is a synoptic prediction for Europe generally.

The first few days will show the Atlantic flow holding temperatures above normal in most of Europe but with temperatures starting to fall to near average values above about 50 N. The jet weakening significantly with some amplification of the flow way out in the Atlantic. Cold air and pressure rises intensifies later in this period. About a 33% expectancy of a fall in pressure to the southwest of the British Isles and into Europe. This phase is crucial if colder air is the be advected from the NE across mainland Europe and the UK. 

 C

[shedhead]

OK . this is the latest. In the fields of high-resolution variations models, a portal internet service provides short and medium range predictions for snowfall and in -house longer term forecast . Current calulations are for the period 10-24 th January 2014 and is a synoptic prediction for Europe generally.

The first few days will show the Atlantic flow holding temperatures above normal in most of Europe but with temperatures starting to fall to near average values above about 50 N. The jet weakening significantly with some amplification of the flow way out in the Atlantic. Cold air and pressure rises intensifies later in this period. About a 33% expectancy of a fall in pressure to the southwest of the British Isles and into Europe. This phase is crucial if colder air is the be advected from the NE across mainland Europe and the UK. 

 C

Thanks for that C....some crumbs I guess, but the 33% you quoted means crumbs pretty much sum things up imo.

[Bristawl Si]

Thanks for that C....some crumbs I guess, but the 33% you quoted means crumbs pretty much sum things up imo.

Is C's latest post a 'downgrade' from him? His posts seemed more bullish re cold and snow a few days ago.

Is C in a weather organisation over there, by the way - seems to indicate sources in many of his posts. Just wondering?