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Model Output Discussions 06z 04/11/16

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4 minutes ago, Man With Beard said:

Believe it or not I think Dec 2014 had a two week spell, not cold like this tho

Snow fell on 26 december then high sat over us for the next week giving ice days and some really hard frost at night.... is that what your thinking of??

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Plenty of below average / cold weather on the Gfs 18z tonight with even some wintry ppn later. I feel we are going to be seeing some wonderful cold eye candy charts soon.:cold-emoji:

ukmintemp.png

h850t850eu.png

h850t850eu (1).png

prectypeuktopo.png

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18z GEFS is the first to show fairly strong signal of re-amplifying the pattern (considering the range) after the collapse of the our initial block. Difference being is how the PV/Pacific ridge/Artic high is handled this leads to the difference in output. It should be noted that not all runs end with us in a favourable position but there are good number (~40%) that put us well onto the tracks of cold spell for mid month with ~20% in a sort of grey area. 

Exciting times ahead with many more upsets to come.

 

Edited by SN0WM4N
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24 minutes ago, Connor Bailey Degnan said:

Hope the cfs is onto the right lines. OH MY WORD

Screenshot_20161129-234758.png

Screenshot_20161129-234601.png

its been showing this type of setup for the past few days now from mid month onwards just like the met office so there is something going on those charts even put december 2010 to shame 

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We are in for something special * Very Soon * This is going to be an EPIC WINTER ' ~~ Just like the ones we use to know .........

:cold:Fantastic Charts ' Best i have seen in Yonks .:cold-emoji:

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4 minutes ago, A Frayed Knot said:

We are in for something special * Very Soon * This is going to be an EPIC WINTER ' ~~ Just like the ones we use to know .........

:cold:Fantastic Charts ' Best i have seen in Yonks .:cold-emoji:

of death kiss :wallbash:

 

 

 

:)

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20 minutes ago, igloo said:

its been showing this type of setup for the past few days now from mid month onwards just like the met office so there is something going on those charts even put december 2010 to shame 

The charts modelled there by the cfs are as severe as 1962/63.

Far too early to say it'll be anything like that but incredibly good signs 

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I think there is way too much cherry picking going on here now of looking at charts which would be wintry then linking them into the hype that surrounds the winter ahead, as per ever in the weather its about the short/medium term and for now, there is no charts which indicate snowfall.

That said, we got a situation where this stubborn high over the UK may lead to better things to come and who knows, may come before all this mid December hype. On the other hand, many runs suggest the high will eventually sink and we start to pick up a mild SW'ly although this is far from a gurantee however a more likely solution than a cold/snowy one basing on many runs.

Really when chasing cold/snow set ups, they will actually start to appear in the medium term and we go from there sorting out the details, no point in cherry picking charts in far reaches in FI then because 2 or 3 runs in succession has a similar outcome does not mean a trend as it will eventually change to something else.

The pacific ridge that is forecast to hit the Arctic and potentially split quite a strong PV there atm is on the cards but how this works out is far from certain and how it interfere with our weather is certainly not clear cut and that is why its probably best to take it one step at a time, not big steps and looking out for trends what might happen during mid December when its over 2 weeks away!

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UKMO goes on a shortwave frenzy and from hero to zero this morning sending most of the energy over the block.

Even the mediocre GFS is better.

UN144-21.GIF?30-05gfsnh-0-144.png

At least GFS is staying away from any potential Southwesterlies as the weather grinds to halt.

gfsnh-0-192.png

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Yes  ukmo is a step back from yesterdays runs  - really dont know what to make of it all at the moment, the Gfs is a very cold run but who knows, we really could do with the Atlantic slowing down sometime, soon!

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9 minutes ago, northwestsnow said:

Yes  ukmo is a step back from yesterdays runs  - really dont know what to make of it all at the moment, the Gfs is a very cold run but who knows, we really could do with the Atlantic slowing down sometime, soon!

It's anticyclonic as Karl( Frosty) says :D, so dry and fairly chilly outlook still. But as far as progressing the output toward blocking in better positions for a cold upper flow to set up within 10 days or so, this mornings Op output is all kinds of, "meh"

A bit like toast without butter.

Hopefully the ensembles are a bit more interesting but we are in for the long haul on this one.

 

 

Edited by Mucka
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17 minutes ago, Mucka said:

It's anticyclonic as Karl( Frosty) says :D, so dry and fairly chilly outlook still. But as far as progressing the output toward blocking in better positions for a cold upper flow to set up within 10 days or so, this mornings Op output is all kinds of, "meh"

A bit like toast without butter.

Hopefully the ensembles are a bit more interesting but we are in for the long haul on this one.

 

 

Yup, UKMO looks cold,as does GFS. However-

Rukm1441.gif

Its very difficult to see how we get any kind of retrogression from there, the high has sunk back into Europe and the jet is firing away in the Atlantic.

As mentioned,the UMKMET is a big step backwards this morning- you are right i think mucka, this is going to be like pulling teeth getting the retrogression we need..

 

Edited by northwestsnow
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10 minutes ago, northwestsnow said:

Yup, UKMO looks cold,as does GFS. However-

Rukm1441.gif

Its very difficult to see how we get any kind of retrogression from there, the high has sunk back into Europe and the jet is firing away in the Atlantic.

 

Absolutely. It would be a case of waiting for the high to slowly sink and a trough to dig in from the North to reamplify the pattern and start again.

GFS ensembles show an interesting split out to the mid term though. some are much more progressive and really quite flat in relative terms, while others conversely want to sharpen the pattern much more.

Seems the operational output we have seen thus far is only one side of the argument rather than a statement of fact for now. 

Examples below.

gensnh-3-1-168.pnggensnh-8-1-168.pnggensnh-14-1-168.pnggensnh-18-1-168.png

gensnh-1-1-168.pnggensnh-4-1-168.pnggensnh-9-1-168.pnggensnh-20-1-168.png

Edited by Mucka
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1 minute ago, Mucka said:

Absolutely. It would be a case of waiting for the high to slowly sink and a trough to dig in from the North to reamplify the pattern and start again.

GFS ensembles show an interesting split out to the mid term though. some are much more progressive and really quite flat in relative terms, while others conversely want to sharpen the pattern much more.

Seems the operational output we have seen thus far is only one side of the argument rather than a statement of fact for now. 

Whats really suprised me is the UKMET 00z run, it was evidently very wrong at t96 yesterday. Guess it highlights the fine tuning of the energy distribution and the knock on effects of it...

Maybe its a 'wobble' from ukmo but from a historical perspective, once a model backtracks from a colder evolution, it never or rarely seems to go 'back'...

Clearly, its complex, either way, its a chilly outlook, no point over analyzing and getting ahead of ourselves with so much disparity at such short notice...

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GFS ensembles.

By day 10 there are 0 runs bring colder uppers (-4 or less) into central England.

By day 11 there is 1 run.

Bay day 12 there are 3 runs

By day 13 there are 7

So while some of those are hardly spectacular winter charts at least there is a growing signal for cold arctic air in deep FI.

My unapologetic cherry picks for this morning are p7.

gensnh-7-1-324.pnggensnh-7-0-324.png

and p9

gensnh-9-1-300.pnggensnh-9-0-312.png

graphe6_1000_260_88___.gif

Edited by Mucka
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Come on guys, the UK D6 charts are woeful when it comes to HP -v- LP, they are akin to D10 ECM charts. I rarely pay any attention to them as clearly they have issues.

My thoughts are that we remain in a holding pattern where the PV remains subdued but there is no forcing to create a more prolonged amplified pattern. It shows that even with a weak PV you need the right synoptics to get long term cold. 

We have gone from the Russian/Siberian High & Azores mid-latitude quasi block setup to an Azores & Pacific HP combo.But again both haven't the heart to be anything but topplers if they do venture into semi-higher latitudes, so effectively still a rather mobile NH pattern within those confines.

Of course as time passes the PV gains a bit more energy just to make any meridional pattern a little bit tougher.

It looks pretty clear we have a sinking high around D8-D10 and its direction of fall will define the upper flow over the UK, with GEM bringing us a warming (average T850s >8c above normal) whilst the GFS a mild flow (T850s +4c above average). As that sinks the cycle starts again, and the next wave from the Azores pushes towards the UK. I am sure the FI GEFS will have some producing  stellar runs, but that has been the modus operandi for weeks and it may be better to assume the status quo until one of these elusive background signals change the pattern. However that has low confidence as the second pulse from the Azores after D10 and the sinking high could be difficult to model at this range. 

Being honest it is hard to see any cold/snowy pattern developing by mid-December but the potential remains clear and hopefully its just a matter of time.

gfs-15-216.png

gem-15-222.png

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3 minutes ago, IDO said:

Come on guys, the UK D6 charts are woeful when it comes to HP -v- LP, they are akin to D10 ECM charts. I rarely pay any attention to them as clearly they have issues.

 

Being honest it is hard to see any cold/snowy pattern developing by mid-December but the potential remains clear and hopefully its just a matter of time.

 

That's not what the stats say and where did anyone say UKMO day 6 should be taken as gospel?

On the second statement, which is it, clear potential or hard to see cold/snow prospects? .

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I wouldn't get too hung up about deep FI charts. Agree little sign of any snowy weather or deep cold fairly mundane quiet weather coming along.

One thing intrigues me is why is ukmo T96 is wrong pretty much the same as any other model where is it wrong???

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Today

Quite a hefty frost this morning in Wales the Midlands and southern England and the clear conditions with light winds will continue during the day, Further north more cloud and higher temps will be the order of the day and this is also the case for Scotland where there will also be a brisk NW wind and even some rain in the far north. Tomorrow will be cloudier for most but still areas of frost in the south albeit not as extreme as today.

1hourprecip_d02_10.png1hourprecip_d02_17.png2mmintemp_d02_44.png

Just to take a general overview of this morning's and perhaps a quick look at a couple of salient features in the reasonable time frame. Essentially it's just a variation on a theme which remains the interaction of the main players, distribution of the upstream energy, the main trough and the high pressure over the UK. Regarding the latter, more specifically the HP stays put while a couple of the troughs deconstruct making no difference at all to the overall pattern. From 24 hours ago the most noticeable difference is the sharpening of the Aleutian ridge. (which as an aside is assisting introducing some very cold air into Alaska and NW Canada)

gefs_z500a_5d_nh_43.png

Some detail. The cut off upper low to the south west spawns a another low from it's northern quadrant around T150 which drifts just south of the UK and which initiates a slack area of low pressure over France with outbreaks of rain which may just sneak into the south. This slowly fills whilst at the same time a weak trough emanates from the main trough to the west and tracks slowly east but is snuffed out eventually by renewed ridging NE from the Azores HP. before it can make landfall

gfs_z500a_natl_26.pnggfs_6hr_precip_eur3_26.pnggfs_6hr_precip_eur3_32.png

A quick summation. The UK remains under the influence of the HP (keeping in mind the above). So dry with surface temps probably a little below average but the usual caveats apply to this.

Edited by knocker
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Up to day 11...much n such the same.... high pressure slowly giving way to the atlantic... but the GEFS after this point could be anyones guess if the ensembles is anything to go by. Still have a gut feeling that things will change mid december. 

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