Model Output Discussion; into 2015

[Frosty.]

I don't think that's strictly true blue armry, there is a lot of cold weather on the gefs 12z perturbations next week alone, especially further north with a risk of snow and also some fine frosty weather, nothing of note is a little dismissive of what's shown.

[BlueHedgehog074]

Don't ever be afraid to post what you think. I think the mods do a great job on here but maybe a piece of

advice to them would be to reassure people more that they shouldn't be afraid to post their thoughts on the models.

Just saying, as they say

 

You make a good point, there. This thread is certainly free for anyone, regardless of their ability, to post in. As such, if you're a new model reader who wants to have a go at doing a post, then please feel welcome to have a go. Doesn't matter either if it's not totally accurate (especially since we all have our own viewpoints of the models, and that we're all here to learn). Despite some of the problems that arise in here at times which, I can understand, can make the thread feel unsettling at times, we're generally a nice bunch. We will usually try to come to the rescue and stamp-out unneeded/disrespectful content in this thread while, at the same, allowing enough room for some emotions and some fairly heated debates, regarding the models, in here. 

Edited December 29, 2014 by DiagonalRedLine

[Kentspur]

I found some wintry GEFS 12z perturbations in the T+168 hours timeframe so potential for snow next week can't be ruled out. :-)

Good for the North! The south west looks like it's virtual bbq conditions in some of those charts lol

[Barry12]

I found some wintry GEFS 12z perturbations in the T+168 hours timeframe so potential for snow next week can't be ruled out. :-)

 

But they won't verify, pointless frosty mate

[Frosty.]

But they won't verify, pointless frosty mate

Yeah but at least there is hope mate, the situation is far from hopeless in my opinion.

[MP-R]

Good for the North! The south west looks like it's virtual bbq conditions in some of those charts lol

 

More likely the southeast. The southwest will receive a large amount of rainfall remember. In these setups the southeast can escape largely dry with temperatures in the 10-14C range. Happened all too often when I was at uni in Egham.

[nick sussex]

The ECM looks more like the GFS over Europe but theres zero agreement upstream between the outputs at T144hrs.

 

It does take a shallow low eastwards, could be some snow on the northern flank of that low for Scotland, I expect when the ECM postage stamps come out that there will be a wide spread of solutions at T120hrs.

 

NCEP have highlighted the complete dogs dinner upstream:

 

MODELS ARE STILL STRUGGLING WITH THE CLOSED LOW EJECTING OUT OF
THE SOUTHWEST AND ARE STILL SHOWING A LOT OF SPREAD WITH IMPULSES
OF ENERGY CUTTING THROUGH AND DIVING DOWN THE UPPER RIDGE IN PLACE
OVER THE EASTERN PACIFIC.  BOTH OF THESE PROBLEM AREAS LEAD TO
PHASING/TIMING ISSUES DOWNSTREAM WITH DEVELOPING A SURFACE LOW
OVER THE EASTERN U.S. THIS WEEKEND.  SINCE EACH PIECE OF
DETERMINISTIC GUIDANCE IS STILL HAVING ITS OWN RUN-TO-RUN
CONTINUITY ISSUE...THE WPC DAY 3-7 FORECAST RELIED HEAVILY ON
ENSEMBLE MEANS.

 

[Great Plum]

ECM hasn't followed the ukm's lead at 144 sadly - no ridge apparent...

ECM: http://www.wetterzentrale.de/pics/Recm1441.gif

UKM: http://www.wetterzentrale.de/pics/Rukm1441.gif

[damianslaw]

All models in agreement of the current high moving away southwards allowing a westerly feed as we enter the New Year. GFS as it often does powers up the atlantic with some very unsettled windy wet weather forecast for the early part of the month- with nothing relenting.. mmm not too sure it will have such energy. UKMO keener on a weakened atlantic flow allowing stronger ridges to develop ahead of advancing fronts - certainly not a full on atlantic attack but a mobile one all the same. ECM a little inbetween. There does appear to be a signal the azores high will stay close to southern shores and wants to ridge northwards still and I wouldn't be surprised to see it put up a fight against the atlantic allowing more pronounced ridge development.

 

Though the models don't show a fast track to anything particularly cold anytime soon, the events of recent days prove how changes can occur in short time periods- very few models forecast the track of the Boxing Day low very well until the near timescale, and some were still not convinced on a settled spell thereafter even 48 hours before. It proves changes do often crop up at short notice and catch the models out - even when under a mobile atlantic set up.

[TEITS]

Just a quickie but based on the comments in the strat thread. If you're looking for the next cold spell then you would be better off looking at the N Hemisphere charts in distant F.I.

 

http://modeles.meteociel.fr/modeles/gfsp/runs/2014122912/gfsnh-0-384.png?12

 

Im quiet encouraged at what may develop from mid Jan onwards.

[Cloud 10]

ECM hasn't followed the ukm's lead at 144 sadly - no ridge apparent...

ECM: http://www.wetterzentrale.de/pics/Recm1441.gif

UKM: http://www.wetterzentrale.de/pics/Rukm1441.gif

 

Not often you see that much difference between the European models at that timescale,and probably to do with the sudden  reversal of zonal winds right through the stratosphere/troposphere.

 

 

UKMO maybe over-reacting here?

[10 Days Away]

A rare post from me in this thread.

The GFS does seem to be receiving alot of attention at the moment for it's zonal outlook over the next couple of weeks, with seemingly little evidence to support anything other than a generally Westerly flow.

However, I cannot see any reason why the UKMO is not onto something with its last two runs bringing in a slightly more amplified and subsequently settled pattern around the 120 / 144 mark.

Yes this may get flattened out and a return to a Westerly flow may be expected to follow but that is two consecutive runs the UKMO has thrown out now showing such a pattern (the 0z run at 144 started the shift to a more settled outlook).

I hope I don't get shot down for putting forward an alternative view to the 'two weeks of Westerlys' projected by the GFS but there is nothing to suggest that the UKMO will not verify as it has been fairly consistent so far this winter.

Fascinating stuff that's for sure and who knows if we can get the high pressure in situ over the UK who knows what might develop from there?

Eyes down for the ECM...you never know it might even show some support for its European neighbour?!

 

 

You should post more , some others, less! 

[Long haul to mild]

Just a quickie but based on the comments in the strat thread. If you're looking for the next cold spell then you would be better off looking at the N Hemisphere charts in distant F.I.

 

http://modeles.meteociel.fr/modeles/gfsp/runs/2014122912/gfsnh-0-384.png?12

 

Im quiet encouraged at what may develop from mid Jan onwards.

Yes, that is probably the focus now. The next 10-14 days don't look great in terms of the pattern with the spell of westerlies and potentially stormy conditions set to arrive. However if the stratosphere continues to warm then we may start to see some better trends in FI soon as the vortex has some pressure applied to it.

 

Lots of time left this winter to get some good cold spells.

[dragan]

You should post more , some others, less!

You like it because it suggests possible (unlikely) cold. ECM so far, goes with the westerly regime.

[Frosty.]

Keep the faith, there are still approx 60 days of winter left..jeez that's not much is it :-/

It's a turbulent pattern coming up, very undulating with ridge, low, ridge and occasional disruption with some buckling of the jet. I think we will have a mix of mild and colder spells in the next 2-4 weeks with some snow, some frost and lots of wind and rain. The Scottish mountain resorts could have a lot of snow, as they did last winter.

[Harsh Climate]

Strictly from the position we currently find our selves in (No real chance of sustained cold/snow for the next 1-2 weeks), the ECM is banging this evening!

 

 

As teits said, all eyes must be on the northern hemisphere and any potential warming in this area.

 

Yes the very end of the run on ECM but the PV is getting the life squeezed out of it, firstly warm air advection from the alaskan region, to high pressure trying to join up with it from the azores. If this run was to go any further, the only outcome would be good high lattitude blocking and colder/blocked, possible snowy weather for the UK. Hope the ECM can follow this trend over the coming days : )

[nick sussex]

The ECM looks similar to the 00hrs run in its overall pattern.

 

It does split the PV again, I'm wondering whether we're seeing a quick response to the strat warming over Greenland.

 

If by some miracle those low heights finally relent over Greenland then given the chunk of PV to the ne theres a lot of cold air to tap into but still early days.

 

A proper Greenland block has gone missing over the last few years, I'm still not sure we can manage that, it depends on whether the PV remains split or whether it reforms quickly.

Edited December 29, 2014 by nick sussex

[Duane S.]

Nice tease from the ECM, no surprise looking at the strat charts, shame it can't happen though because apparently cold is not possible before Mid Jan!?!

 

Rule nothing out folks, as I posted yesterday, the eye candy charts are nearly upon us.

[IDO]

You should post more , some others, less! 

 

UKMO does that a lot; tries to make more of transient ridges. It is usually last to correct as we move towards T0. GEM, ECM and GFS have all shown this over the last few runs (and continue to spin this line on the odd run) and have moved on. UKMO will correct tomorrow if previous experience is anything to go by. It was only a few weeks ago they did the same thing. Though a transient push north within the pattern is possible.

 

This upcoming pattern will change by mid-Jan at the latest if the MJO forecast is correct. 

 

  MattHugo81

Wx Doctor in the house; Hoping for cold and wintry weather?....a case of don't look at the models and come back in 10 to 14 days! #nocold

29/12/2014 18:56

 

^^^As many pros have been saying so its not just the models.

 

I doubt the SSW before then and the warming also after then, though there remains promise for one of them:

 

  antmasiello

The new 12z ECMWF pretty much destroys the 10mb vortex. Wow

29/12/2014 19:03

 

So again, mid Jan...

[SLEETY]

Yes patience is the key this year.At least there will be plenty of cold air to tap into if things turn into our favour later.Its just bottled up in the Arctic at the moment.All good things to those who wait

[TEITS]

Keep the faith, there are still approx 60 days of winter left..jeez that's not much is it :-/

It's a turbulent pattern coming up, very undulating with ridge, low, ridge and occasional disruption with some buckling of the jet. I think we will have a mix of mild and colder spells in the next 2-4 weeks with some snow, some frost and lots of wind and rain. The Scottish mountain resorts could have a lot of snow, as they did last winter.

Indeed Frosty and lets be honest suppose the next 15 days are mild but we have a prolonged 7-10 day cold spell at the end of the month. Even if the remainder of the winter thereafter is mild I wouldn't be disappointed. The simple reason being is you have to accept the climate we live in and remember winters like 62- 63 are the exception. The winter of Jan 87 was fantastic in my opinion and yet it was mild apart from the exceptional spell in Jan.

 

Sorry if this appears off topic Mods but lately I have read many negative posts and even "winter is over posts".Remember +384 only takes us to mid Jan!

[bluearmy]

The ECM in the strat is consistent with the split and it's real eye candy at 10 hpa

Until we see gfs show some consistency at 10 days in the strat, we can't really get too confident but the highest resolution models high up (ECM and jma) look similar at day 8.

Could do with the extended ECM clusters beginning to show a quick response at the very end of their run. if they are seeing the same as the op, some of them must show a quick strong -AO apparent by day 14.

Perhaps a day or so too early to get hung up on that though.

[stratty]

Nice tease from the ECM, no surprise looking at the strat charts, shame it can't happen though because apparently cold is not possible before Mid Jan!?!

ECH1-240.GIF.png

 

Rule nothing out folks, as I posted yesterday, the eye candy charts are nearly upon us.

.........fingers crossed! Hopefully we can see that gap continue to open between the two air masses south of Greenland

 

[Mucka]

I think the ECM 10 day chart is roughly following expectations from early strat warming feedback weakening and displacing the Canadian PV thus pushing a lobe further SW and amplifying the downstream pattern? (our upstream)

That is the sort of pattern I am looking for in FI so nice to see it modelled at least even though it is currently the weakest of weak signals. (and possibly too quick)

 

Edited December 29, 2014 by Mucka

[johnholmes]

Models have bias'. NOAA and ECMWF readily accept this. The reasons probably too complex to go into.

12z GEFS - nothing of any note within the next fortnight from a coldie perspective.

However, deep lows and wind /rain + chance of some snow via runners still evident.

Ecm rolling out and I suspect most informed eyes will be well above the trop looking ahead to the second half of jan. The six day chart will carry some interest re the ukmo GM.

 

Of course all models have bias but not something that is put there and as they realise there is a bias the modellers 'tweek' to correct it. They constantly strive to try and make their model be a prefect reflection of what the physics of the atmosphere would give IF the errors that develop due to a variety of factors not human led were not there. Yes it is immensely complicated and the further a model attempts to predict ahead the more the problems grow. That will not stop the professional making constant efforts to improve things mm by mm each decade!