Model Output Discussion; into 2015

[Polar Maritime]

Crucial time coming up for coldies.

 

Could i ask why ? 

[IDO]

Looks like the GFS has moved towards the ECM tonight with more amplification. The GEFS have been useless so far this winter, especially from day 7 onwards. I suppose this is why the Met Office don't take the GFS into account when making there forecasts.

 

I don't think the two attempts at ridging at D6 and D10 will make any difference to the long wave pattern. The D12 GEFS are pretty much in line with the last 4-5 runs: 

 

 

The PV is moving around our side of the NH and all the blocking is on the other side so I cannot see any amplification being anything but temporary. Though conversely introducing a transient HP to the UK would bring in more of a TM flow than the recent runs have shown (see GFS 12z op). GEM was one of the first models to spot these early December like ridge/trough combos and it still runs with them:

 

D7:   D10: 

 

It's ensembles are close to the GEFS at D12. At D16 the GEFS show no sign of blocking over our sector but there is no discernible pattern apart for the propensity for the mean PV lobe to remain to our NW: http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=384

 

The MJO does not get interesting till after mid-Jan and the SSW is not likely till after then so we will have to be patient IMO.

[blizzard81]

Could i ask why ? 

By all means - current warming of the strat, lets hope it pays dividends in the first half of Jan (heart of winter!) :smiliz19:

[MP-R]

Not my type of winter at all. The winters of the last 20 years plus have been dominated by this dross.

I think the main culprit is the warming of the oceans in recent decades.

 

Tbf the charts shown are more akin to November and December than January/February so again it's just bad luck. I'm hoping that with the SSTs a few degrees colder than a month ago, we will be able to scrape more wintriness out of potent PM shots, of which there are plenty shown across all models. That's the positive part.

 

Besides that, there is nothing positive about potentially damaging winds from some unusually deep depressions. We really desperately need some amplification upstream and some undercuts around the UK waters. Echoing what was asked earlier, I would also like to know why the most potent area of the PV 9/10 has to be over Greenland. Out of all the places, I would have thought just above the Gulf Stream isn't amongst the coldest!

[MPG]

The Gfs in particular looks like it's cranking up to Chuck some weather bombs our way with explosive cyclogenesis as we saw recently, a really potent mix of wintry weather with spells of heavy rain, sleet and snow and severe gales to storm force winds at times but also a few calmer frosty interludes.

Great if your up a mountain, but weather bombs, rain an flooding is not welcome....if that's what occurs. There is a disconnect, MJO not playing simples. If you like PM shots it's good news.

[mulzy]

The Gfs in particular looks like it's cranking up to Chuck some weather bombs our way with explosive cyclogenesis as we saw recently, a really potent mix of wintry weather with spells of heavy rain, sleet and snow and severe gales to storm force winds at times but also a few calmer frosty interludes.

 

Sleet and snow mainly over Northern hills, rain for most of lowland Britain.  Nothing particularly wintry to be honest...

 

http://modeles.meteociel.fr/modeles/gens/runs/2014122812/graphe3_1000_306_141___Londres.gif

Edited December 28, 2014 by mulzy

[blizzard81]

Tbf the charts shown are more akin to November and December than January/February so again it's just bad luck. I'm hoping that with the SSTs a few degrees colder than a month ago, we will be able to scrape more wintriness out of potent PM shots, of which there are plenty shown across all models. That's the positive part.

 

Besides that, there is nothing positive about potentially damaging winds from some unusually deep depressions. We really desperately need some amplification upstream and some undercuts around the UK waters. Echoing what was asked earlier, I would also like to know why the most potent area of the PV 9/10 has to be over Greenland. Out of all the places, I would have thought just above the Gulf Stream isn't amongst the coldest!

I am not that technical when it comes to such matters but I guess this is linked to the north atlantic oscillation (NAO).

Like I said earlier, the sst's have a huge bearing on our weather and not least the NAO. Warm waters up towards the south

and east of Greenland aides the formation of high pressure in that area and vice versa.

[Jason M]

Looking through the GEFS, I'd agree with IDO. No sign of any northern blocking although ptrb 7 does offer a cheeky toppler to finish. Essentially they are zonal though and without some major intervention from the strat, difficult to see how we will break out of this.

Having seen similar many times over the years this pattern will tend to encourage heights to our SE in response to the PV being sat to our west or northwest. This would likely increase the prevalence of TM shots over time.

it would be nice just to see a bit of eye candy in FI. Even the pub run has been sober of late :-)

[Frosty.]

I think most on here are looking for something MUCH better than that.

I certainly am, I want a Beasterly as most of us but at least we have a wintry mix ahead of us which is better than benign mild dull weather in my opinion. It's a very wild outlook, this week is the calm before the wintry storm so to speak.

At least there is no Bartlett slug on the horizon to eat away valuable winter time.

Edited December 28, 2014 by Frosty.

[blizzard81]

Yes, as I predicted earlier, the ECM has dropped the amplification towards Greenland at T144.

This model really needs to get this problem of over amplification in this area at T168 onwards sorted.

It has gone on for far too long imo.

Edited December 28, 2014 by blizzard81

[Barry12]

IDO, if the ECM is so useless past day 6, why do the Met Office use it over the GFS?

[karyo]

Unsurprisingly, the ECM has come down to earth with a much less amplified 12z output.

 

The potential for a wintry northwesterly at the 144 - 168 hour range has vanished apart from the highest tops of Scotland.

 

Matt Hugo wrote an excellent post on the stratosphere thread yesterday explaining why the current stratospheric warming will not benefit our side of the Atlantic. I suggest people read it.

Edited December 28, 2014 by karyo

[MP-R]

I certainly am, I want a Beasterly as most of us but at least we have a wintry mix ahead of us which is better than benign mild dull weather in my opinion. It's a very wild outlook, this week is the calm before the wintry storm so to speak.

At least there is no Bartlett slug on the horizon to eat away valuable winter time.

 

I think having had active Atlantic weather in October and November I'd rather have the benign dry weather lol. I love a good storm but one after the other with no let up becomes a pain.

 

Anyway, wrong thread for preferences.

 

On a more relevant tack, I will contain by displeasure of the models and consider next weekend a tipping point, and here's why:

 

GFS

 

ECM

 

 

A ridge of heights poking northwards, and attendant ones poking southwards and low pressure to the west negatively tilted. That would be a chance at undercutting unless it flattens out in future runs. That's the best I can muster for now.

[bluearmy]

Interesting part of ecm op run approaches where we wait to see if the Siberian shortwave will close off the Arctic ridge and head to Canada

Re the ecm op - Exeter won't reallyuse it post day 6/7 unless it has good ens support.

[blizzard81]

The difference between this morning's ECM op and tonight's is laughable!

If I was to get my positive head on - model chaos due to strat warming?

If not then God help us coldies

[Frosty.]

 

The potential for a wintry northwesterly at the 144 - 168 hour range has vanished apart from the highest tops of Scotland.

 .

So that's it then, are you throwing in the towel because of 1 operational run, don't you think the next run could swing back to something better. I despair sometimes.

[karyo]

So that's it then, are you throwing in the towel because of 1 operational run, don't you think the next run could swing back to something better. I despair sometimes.

Maybe if you make the effort to read Matt's post you will understand...

[IDO]

IDO, if the ECM is so useless past day 6, why do the Met Office use it over the GFS?

 

Another example of ECM is yesterday's 1055hPa Alaskan High: 

 

Tonight's run: 

 

We have to accept that any height rise after D8 has a very low chance of verifying especially when there are triggers, like change of patterns, mid-lat lows, Pacific Ridge, etc.

 

I suggest that the experts are well aware of the ECM quirks and use its mean and ensembles as well as other models to work out the probabilities of upcoming patterns. It remains the best op model pre D6 and its ensembles are also the best.

Edited December 28, 2014 by i'm dreaming of...

[Polar Maritime]

Can we just all calm down please, And respect one-another  :smiliz19:

[blizzard81]

So that's it then, are you throwing in the towel because of 1 operational run, don't you think the next run could swing back to something better. I despair sometimes.

I would understand your comment more if the previous run was brilliant. Problem is, the 00z run was pretty mediocre with

a terrible ending. The 12z run is now much worse. We all talk about trends on here. Well, the trend is bad. I will shout cold

from the roof tops with the best of them given half a chance but I am also a realist. The realist in me tonight says the Netweather

winter forecast looks shaky to say the least.

Edited December 28, 2014 by blizzard81

[MR EXTREMES]

So that's it then, are you throwing in the towel because of 1 operational run, don't you think the next run could swing back to something better. I despair sometimes.

To be fair frosty when the ecm throws an awful run like tonight's out at t168 and t144 ID be very concerned indeed.

Still no meaningful northern blocking to our nw or ne but plenty of Southern blocking.

Possibility is the Azores heights might well make an appearance into the uk from the looks of where it's heading then even further north than the gfs.

If cold is what your looking for.

So possibly dry frost a feature under heights moving up from the south southwest.

[Smiler1709]

Right that's it, it's the 27th of December and winters over!!!

Because the models at the moment say so.....zzzzzzzzzzzzz

[mulzy]

Can we just all calm down please, And respect one-another  :smiliz19:

 

The current pattern (low heights to the north west and high heights to the south) is VERY poor for sustained wintry and cold weather.  Yes, the outputs can change but at the moment nothing significantly wintry on the horizon.

Edited December 28, 2014 by Polar Maritime
To remove off topic reverence.

[PolarWarsaw]

Maybe if you make the effort to read Matt's post you will understand...

 

What you mean the same posts that a few days ago were talking about promising signs from the strat. Love the fact Matt, Chiono, Recretos and Lorenzo etc fill us with wonderful information about the strat, but they are just forecasters discussing forecasts from day to day, much like those that study every model release during each day of winter. The charts may show a warming on 'our side' tommorrow. Honestly, this thread must do nothing but increase bipolar around the world. Please take a step back and look at the overall picture - do not take every individual post as a guarantee, nor every thread. If jesus himself, drops down to earth tommorrow and tells you that he thinks it'l be cold on February 19th and Karyo's back yard will see 18 inches of snow..it's not guaranteed. 

 

Onto the models - things look fluid and active. Potential for some snow to lower levels with a bit of luck but a westerly regime that will ensure that nobody see's full on and stable cold for long periods of times. Let's see what happens in the coming weeks - however, we are now coming to a time where we need to solidify up on something more sustainable if the OPI forecasts are to be met and the expectations on this winter from some of our more senior forecasters! 

 

Happy new year NW!

[blizzard81]

And before anyone jumps down my throat for calling an early winter's over post, as long as that arctic high

languishes over the other side of the pole then we have next to no chance of a true cold spell this side of the pole,

simples! All this talk of amplification over the pacific is all well and good but we need this to come to our side.

People will say Pacific amplification gives us more of a chance but having viewed this over many years, I am not so sure.

Edited December 28, 2014 by blizzard81