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

[Mucka]

Please be so kind as to refer to the post above by draztik showing the 12z NAEFS anomaly chart - virtually identical to the 0zs giving no signal for anything but average to mild and unsettled.

If I can see a signal to cold & there are tiny hints, I will post it but we have to be realistic at the moment.

 

You don't consider the ensembles tiny hints then?

They have clearly shown an average to cool/cold signal as we progress through the second week of Jan for sometime.

or the MetO forecast for the second week of Jan?

"Temperatures will initially be near normal but there are indications of it then turning colder"

 

I would say there are no tiny hints for mild rather than cold after the first week of Jan

Edited January 1, 2014 by Mucka

[Snowy.Eth]

Not in the old days tony - we chased and chased a northerly toppler for week after week, month after month. Ecm only went to T168 and GEM to T144 so we only had gfs to look at for eye candy.

Those were the days and going through a winter with nothing.

[nick sussex]

Any news on the potential snow for Saturday!!models backed down or do we still have a chance?.ian ferguson was talking about it yesterday and said it was quite a strong potential as well!!

Still quite uncertain depending on what output you look at, the GFS takes a low ene and shows some snow on the nw flank for southern Ireland and into the far north, the UKMO has a weaker feature running ne shown on the fax chart:

 

 

It does look very marginal though, perhaps helped if the flow slackens out, still lots of time for more changes.

[Purga]

You don't consider the ensembles tiny hints then?

They have clearly shown an average to cool/cold signal as we progress through the second week of Jan for sometime.

or the MetO forecast for the second week of Jan?

"Temperatures will initially be near normal but there are indications of it then turning colder"

 

I would say there are no tiny hints for mild rather than cold after the first week of Jan

Mucka, I did say 'and there are tiny hints', perhaps I didn't construct my sentence very well - apologies. I think there is a change in the offing but just how much and how cold or not is very open I would think. If there is a cold signal developing which consolidates over more runs of the NWP and GEFS then great - but we've been let down so many times that I prefer to be rather downbeat which doesn't suit some younger members on here. I would love to see the back of this wet and windy stuff and get some proper winter cold believe me!

Edited January 1, 2014 by Purga

[Frosty.]

I'm looking longingly at that Siberian High on tonight's Ecm 12z op run with it's beautiful mega cold sub 492 dam thicknesses and thinking that wonderful purple core of bitter cold air could be heading in our direction by the second half / later in the month.

Edited January 1, 2014 by Frosty.

[shaky]

Still quite uncertain depending on what output you look at, the GFS takes a low ene and shows some snow on the nw flank for southern Ireland and into the far north, the UKMO has a weaker feature running ne shown on the fax chart:

 

fax72s.gif

 

It does look very marginal though, perhaps helped if the flow slackens out, still lots of time for more changes.

maybe a middle ground solution then and it might go through the centre of england!!see what happens!!

[stewfox]

deleted

Edited January 1, 2014 by stewfox

[lassie23]

This winter goes to show how low solar activity and massive snow cover over Russia has no interaction without uk weather! Also that silly myth that whatever cold and snow develops over north East USA later affects us! Absolute garbage!

I agree! We need a negative NAO to start with.

[SMU]

The zonal train might have just crashed on the 18z......

 

S

[bluearmy]

as the models tighten up the canadian vortex and drift it nw in week 2, we lose the lobe that has been pushing the deep cold into the atlantic and interacting with the stj to create the depressions running at us. however, we see a push of energy thrown from the canadian vortex out towards the w siberian daughter (which will likely become the master in time) across to the n of greenland. this has shown on gefs for some time and now ecm extended ens are showing it. that is usually the signal for renewed mobility in the atlantic.  at the same timepoint, both ecm and gefs extended are expanding lower euro anomolys.  that doesnt make a lot of sense to me. i would expect the azores ridge to be expanding east with this movement of the p/v.  a recent fi gefs theme has been an expanding nw european trough , trending colder with time.  does this fit in with exeter's view of it getting colder, moreso the further north you are ?  too many mixed messages. sticking with the ens mean would make sense but it just doesnt when we know there are very different solutions out there. btw, the ecm control for holland is frigid late on under a sceuro block.

[bluearmy]

The zonal train might have just crashed on the 18z......

 

S

 

what have you seen by day 3 steve ?????  i cant see it and surely 72 hours is too soon for differences? 

[Ali1977]

That looks a nasty low coming in around Monday

[damianslaw]

The Jetstream profile forecasts beyond 144hr mark look much more diffuse and uncertain with indications of buckling and overall a weaker jet.. a weaker jet can only help aid the development of weaker low pressure systems and increase chance of higher heights having a greater influence over the country.

 

Might we be looking at a more NW-SE aligned trough as we move through January becoming unstuck in response to heights building to our NE.

[fergieweather]

Any news on the potential snow for Saturday!!models backed down or do we still have a chance?.ian ferguson was talking about it yesterday and said it was quite a strong potential as well!!

Signal remains in latest output but low probabilities. However, UKMO stress the wintry ppn potential remains one of the key uncertainties for Sat but much will depend on dropping the gradient to facilitate evaporative cooling/lowering of WBFL. But in summary, yup, remains one to watch, for sure. Some high-res output offered up to 5cm snow but the uncertainty really needs stressing before anyone hyperventilates over this one...!!

[UV-RAY]

This winter goes to show how low solar activity and massive snow cover over Russia has no interaction without uk weather! Also that silly myth that whatever cold and snow develops over north East USA later affects us! Absolute garbage!

So many things wrong with this post, first off solar output is spouted by far too many who haven't the foggiest on what they are talking about, incidentally output at this moment in time is relatively high for this cycle but it's more to do with UV output so may I suggest you read up on Joanna Haighs findings. The rest of your post just highlights all the necessary pieces of jigsaw that is needed in order to get cold to these shores. Right back to the model output and IMO nothing has changed a pattern change remains on the cards from around the '10th, the only thing which is up for grabs is how cold and how long. Edited January 1, 2014 by Sceptical Inquirer

[SMU]

what have you seen by day 3 steve ?????  i cant see it and surely 72 hours is too soon for differences? 

 

Models do change at 72- well the fail FS

 

We want a change in the PNA signal for a deeper tighter jet- the old model statistics used to show that the GFS was FAIL @ the PNA block...

 

Watch the positive tilted trough changed to a negative tilt..... GFS has crashed & burned. a 300 mile movement NW in that low @ 120

 

S

Edited January 1, 2014 by Steve Murr

[Captain Shortwave]

Well this is humiliating for the GFS, Scandi ridge downgraded massively, Upstream is slower and more amplified.

So more like the ECM then

[SMU]

GFS jet stream profiles rapidly changing....

 

 

look at the PNA sharpen up over the US

 

12z 126

 

18z 120

 

S

 

[bluearmy]

Models do change at 72-

 

We want a change in the PNA signal for a deeper tighter jet- the old model statistics used to show that the GFS was FAIL @ the PNA block...

 

Watch the positive tilted trough changed to a negative tilt..... GFS has crashed & burned. a 300 mile movement NW in that low @ 120

 

S

 

the east coast low is further inland than the 12z and yes, neg tilt but i still didnt see that coming at T72. gfs is notorious for sticking with its solution out to day 5/6 and then making small adjustments over time to get to where it should be. the differences are not huge but may extrapolate over the next few frames

[nick sussex]

Although the GFS has moved towards the ECM the troughing over the UK is just sitting there waiting to phase with the PV, this really is now the sticking point, zip energy going se and its very difficult to get to anything colder if these phase.

 

Ordinarily even the GFS upstream pattern would be sufficient to deliver the ridge across the top but until the limpet trough shows signs of getting a move on its going to be a frustrating watch!

[pdiddy]

This winter goes to show how low solar activity and massive snow cover over Russia has no interaction without uk weather! Also that silly myth that whatever cold and snow develops over north East USA later affects us! Absolute garbage!

Not so fast!  Surely this kind of statement is best left until March?  Models suggest a weakening of the jet, MetO have gone colder in their 30 day and there are colder members appearing in the ens:

 

http://www.wetterzentrale.de/pics/MT8_Aberdeen_ens.png

 

Can you really be sure there is no interaction?

Edited January 1, 2014 by pdiddy

[swfc]

Well to my untrained eye the 18z looks terrible and nothing like the ecm or 12z?i must be missing something!!!

[SMU]

Well to my untrained eye the 18z looks terrible and nothing like the ecm or 12z?i must be missing something!!!

 

What your missing is 1 assumption.

 

If 1 run of the GFS at 96 can change a low by 200 miles that then changes the hemispheric pattern by 1000 miles

then another shift of 200 miles changing the amplitude of the jet will further change the hemispheric pattern by another 1000 miles.

 

Each shift NW will make the jet a higher amplitude until the jet waved to the point where things support a building a scandi ridge.

 

S

ridge building up at 186- can the GFS work out that lows can under high pressures not through them

http://modeles.meteociel.fr/modeles/gfs/runs/2014010118/gfsnh-0-186.png?18

Edited January 1, 2014 by Steve Murr

[nick sussex]

The ECM could easily go the same way as the GFS 18hrs run because even that's very close to the dreaded phase, essentially here we have the ECM with a good upstream pattern and the GFS still with an okay pattern, either would have been fine without the UK trough love-in!

 

For newbies think of phasing in this set up as giving the PV a tow eastwards because as soon as the energies phase this is what happens, as much as we have been obsessed with the upstream low for good reason this is just one piece in the escape from zonal muck puzzle!

[Mucka]

Although the GFS has moved towards the ECM the troughing over the UK is just sitting there waiting to phase with the PV, this really is now the sticking point, zip energy going se and its very difficult to get to anything colder if these phase.

 

Ordinarily even the GFS upstream pattern would be sufficient to deliver the ridge across the top but until the limpet trough shows signs of getting a move on its going to be a frustrating watch!

 

Very frustrating. It just hangs around allowing the Azores high and European high to build back in before slowly filling and lifting North ensuring no cold uppers get in the circulation. If only it could of sent at least some energy SE or I would rather it event cleared off NE.

Winters like these remind us all of the good old bad old days of model viewing when a glancing Northerly was the highlight of the Winter.

Still, if we do ever get some snowfall this Winter it will be massively appreciated rather than taken for granted.