Model Output Discussion 26/11/2012 18Z onwards

[SMU]

Edited the original post as its supposed to be a comparison with another model- IE UKMO-

S

[Geordiesnow]

Oh well, I was offering hope that the UKMO raw output is right but going from Ian's posts, this seems unlikely now which means we will have to go via the Northerly route, the most riskier route and less snow potential.

Of course if the UKMO is wrong, then at least for our part of the world, its output has been poor with the constant positioning of the trough.

[SMU]

There's something else on that chart which i thought you might have mentioned?...

All the snow spikes?

[cold snap]

Heres a hint to analyizing the 18z V the 12z

empty all your windows / icons to net weather- ready to refresh the forum

Open X2 windows

http://www.meteociel...npara=0&carte=1

http://www.meteociel.fr/modeles/ukmo2.php?carte=1021&ech=6&nh=1&archive=0

keep refreshing one then you can tab back across to the old run to compare storm tracks, pressure differences etc-

those links are GFS V UKMO

S

That means the UKMO have moved towards the ECM mean ( & presume the MOGREPS mean) away from the UKMO Raw.

there was only 2/3 ECM pterbations that were identical to the UKMO at day 5- ^ hence the above commentary

S

So that it's then steve ?

It's not going to happen for now and ukmo model output is just a red herring

[SMU]

Sorry for the one liners-

T54 a large correction towards the NAM/UKMO on the 18z GFS-

also that drags the euro pattern west as well

S

NO Cloud-- The UKMO are adjusting to the CONSENSUS rather than the perceived outlier- that statistically makes the UKMO less likely, however if the consensus is wrong then well...

Wait for the 18z..

d

Edited November 26, 2012 by Steve Murr

[cold snap]

I need a Stella

I mean a 18z stella

[nick sussex]

Changes already with a deeper low and a bit more amplification upstream.

A good start.

Edited November 26, 2012 by nick sussex

[Weathizard]

Very confused by Ian Fergusons posts, so does that mean we may as well ignore the UKMO? Surely if the Met Office recognise their model is not correct they would manually over-ride the things that are wrong? Very confusing and I'm not entirely sure if that means we should be ignoring it or not?

[Cloud 10]

All the snow spikes?

[Ice BIast]

The low is further west at just T60

[Matty M]

Sorry for the one liners-

T54 a large correction towards the NAM/UKMO on the 18z GFS-

also that drags the euro pattern west as well

S

NO Cloud-- The UKMO are adjusting to the CONSENSUS rather than the perceived outlier- that statistically makes the UKMO less likely, however if the consensus is wrong then well...

Wait for the 18z..

d

Indeed Steve at just 60hrs it does appear a reasonable correction west, with heights/angle and lp position.

[fergieweather]

Surely if the Met Office recognise their model is not correct they would manually over-ride the things that are wrong? Very confusing and I'm not entirely sure if that means we should be ignoring it or not?

They are... they do... every day. The raw output isn't what we employ for our public forecasts. Ditto with NAE - only use modified version. Neither are available on web, however.

Edited November 26, 2012 by fergieweather

[Continental Climate]

At least three hundred miles further west i would estimate

[SMU]

One last time ( not speaking for Ian)

If you have one model operational V the ECm op + ENS suite & MOGREPS suite all pointing to something else pattern wise then the common sense element would at best blend the 3, or better still car park the UKMO use the consensus mean & comment on the uncertainty

S

[Panayiotis]

The low is further west at just T60

Yes and (the low to the east of the USA) is much deeper at 63hrs (than the 12z) this should help bring the high pressure northwards into Greenland. Also Greenland high looking stronger at 1028mb instead of 1024mb (12z) Edited November 26, 2012 by panayiotis

[cfallon]

At least three hundred miles further west i would estimate

Apologies, is that good or bad? Learning!

[Matty M]

At T84hrs we want that small low forming to the north of the UK to swing south nice and fast.

If it did we could have a stella run.

[cold snap]

They are... they do... every day. The raw output isn't what we employ for our public forecasts. Ditto with NAE - only use modified version. Neither are available on web, however.

Sorry Ian we all appreciate your input thanks ever so much just need a small bit of clarification here

Are you telling us as things stand that the ukmo model that we see is wrong? Yes or no

[Zenarcher]

At 78 hours on the 18z the low is now positioned where the ECM and UKMO place it also our ridging has been moved slightly West.

[Staffordshire]

Apologies, is that good or bad? Learning!

yup

[Weathizard]

T84, few hundred miles further west, 10mb lower pressure and greenie high 5mb stronger.

[SMU]

We are tracking well on the GFS--

T72 was almost identical to the UKMO -

http://modeles.meteociel.fr/modeles/gfs/runs/2012112618/gfsnh-0-90.png?18

T90 slack air & coldish uppers over the UK = COLD surface.

S

[Geordiesnow]

Shame if the guys at Exeter think the troughing could be wrong on its raw output because the GFS 18Z run looks similar regarding the troughing to the UKMO. Better news by the looks of it on the Atlantic ridge POV also.

As per with the GFS, we seem to have shortwaves all over the place mind!

[HammerJack]

How can I view the model output?

[chionomaniac]

Not really surprising to see the GFS 18Z edge slightly westwards. Following the 12Z Icelandic slp ensemble trend. I expect to see at least a 15 mb increase in Rekjavic pressure at 0000 3/12 on this run.

Will we see that I wonder?