Model Output Discussion 23/11/2012 18Z onwards

[bluearmy]

Might be off topic but ive just realised that the met office have all ready updated their outlook view early this morning. Wonder why that is?? They seem to be going against gfs and ecm it seems.

they will be using ens data, most of which we dont see. ian F will no doubt be along after the trials of the weekend rains to update us but it looks like a positive update to me.

[SMU]

Morning - its funning ive been logging on from my phone to this thread each morning in bed without looking at the output & after reading this mornings highlights- or maybe 'lowlights' Its amazing what opinion you form of what the outputs will show - but also how wide of the mark some interpretations are-

The UKMO again is stunning, 9.5/10- just dropping half a mark because it is perfect.

Interesting, I havent even bothered with the GFS ( & the 06z wont get much commentary)- but i find it funny that the ECM is suddenly returning to the atlantic weather at 240.

its not.

A snow event from the NW across the UK & pressure to build from the NE after that.

Keep it brief today- as I mentioned last night- expect a better run at 120 for the main 3/4 models & expect the UKMO to be near the front of the pack.

Have a good day, the UKMO if it varifies will be bringing a high%age chance of snow by late friday next week-

S

[chiffer]

Definately a positive update, its better than yesterdays outlook. Think with the information they have they only see it going one way (at the moment)

[Cloud 10]

ecm mean looks decent with low spreads across much of the uk. once the cold sets in late in the week, uppers below -5c and thicknesses below 528dam. under what may well be a slack trough, that gives plenty of opportunity for snowfall. its not as if this mean has changed much over the last few days.

Morning BA,do you have an alternative link for the ECM ens? Meteociel still stuck on 12z

[Ice Day]

The BOM continues to be the

Meteociel - Modèle Numérique australien BOM ACCESS

Bank! The angle of attack looks perfect for the whole of the UK, shame it's only the BOM. Can someone now please post 'how well the BOM is verifying this year' to really get the juices going!!!

[Tim Bland]

Best ensembles of the season so far from GFS! Mean uppers at -5 for almost the whole run! We are being spoilt this year http://www.netweather.tv/index.cgi?action=charts;type=ens;sess=

[bluearmy]

Morning BA,do you have an alternative link for the ECM ens? Meteociel still stuck on 12z

whoops - you're right! ecm website shows the mean looking less solid to our nw as we reach day 10 ! ok till day 9.

[SnowBallz]

I think some of you have forgotten - or indeed you may not know - but the BOM model is built on the UKMO base platform, ie: it's essentially the same model, with slight variation to account for SH and, specifically, the Australasian region.

The UKMO sells its forecasting services to foreign meteorology agencies - one of its main revenue generators. So, if you want to extrapolate forward beyond the 144h range of the NH UKMO, take a view from the BOM. However, caveat that with the understanding that each model does have regional tweaking.

[bobbydog]

The BOM continues to be the

Meteociel - Modèle Numérique australien BOM ACCESS

actually, it looks remarkably similar to the UKMO at +144

UKMO-

BOM-

australians could give a XXXX about our weather....

Edited November 24, 2012 by bobbydog

[chris55]

Stunning UKMO and BOM this morning and both very similar, so some consistency between these two models at least

GFS not to far of either,

The evolution of the little SW "slider Low needs watching as rather than spoiling the party it "could" if things fall right, produce some snow on it's eastern edge if the interaction with the colder uppers and positioning is just right. Although at present the influence of the block holds it to far West,

ECM still has the trough to the east to far North IMO.

Edited November 24, 2012 by chris55

[weather eater]

My post of yesterday still stands, the crucial period is now a day further on, so let’s call it 72hrs to 144hrs, we still can’t get any sort of agreement between the big three. UKMO the best of them, ECM pretty similar to yesterdays 12z run in its early to mid range evolution. The GFS looks closer to yesterdays 06z run, however it evolves much as I suggested it could yesterday, we get the SWs merging but then the whole system sinks, leaving us in an easterly airstream. Conclusion more waiting and seeing I’m afraid, At least I'm enjoying it while some of you appear to be getting your knickers in a bit of a twist.

Just looked at the BOM it's actually very similar to the GFS and it merges the SWs in a very similar way.

Edited November 24, 2012 by weather eater

[chionomaniac]

Bobbydog and Chris55 have perfect timing after Snowbalz post!!!

[Cloud 10]

Bank! The angle of attack looks perfect for the whole of the UK, shame it's only the BOM. Can someone now please post 'how well the BOM is verifying this year' to really get the juices going!!!

Don't know how well the BOM is doing in general terms but based on its prediction

and verification for today,i would say more work needed!

today.. 6 days ago..

[VillagePlank]

Here's, the GEFS 00z analysis,

Very interesting to see -8C 850hPa feature in the 68% probability zone for a day and half in the middle, there. Do I dare let myself believe. Just for one minute ....

Edited November 24, 2012 by Boar Wrinklestorm

[Methuselah]

Don't know how well the BOM is doing in general terms but based on its prediction

and verification for today,i would say more work needed!

today.. 6 days ago..

See Snowballz's post, above...

[chris55]

P20 on the GFS ens looks to have the day 10 pattern spot on :winky:

[Severe Siberian icy blast]

Morning - its funning ive been logging on from my phone to this thread each morning in bed without looking at the output & after reading this mornings highlights- or maybe 'lowlights' Its amazing what opinion you form of what the outputs will show - but also how wide of the mark some interpretations are-

The UKMO again is stunning, 9.5/10- just dropping half a mark because it is perfect.

Interesting, I havent even bothered with the GFS ( & the 06z wont get much commentary)- but i find it funny that the ECM is suddenly returning to the atlantic weather at 240.

its not.

A snow event from the NW across the UK & pressure to build from the NE after that.

Keep it brief today- as I mentioned last night- expect a better run at 120 for the main 3/4 models & expect the UKMO to be near the front of the pack.

Have a good day, the UKMO if it varifies will be bringing a high%age chance of snow by late friday next week-

S

Agreed Steve , I did say that, the ECM looks a typical undercutting low so it could produce copious amounts of snow in that situation as its positioning on the ECM is perfect to slide across the country , strengthening the block to the north as it does so .

[Methuselah]

P20 on the GFS ens looks to have the day 10 pattern spot on

In 10 days, we'll know for sure...

[I remember Atlantic 252]

UKMO 144 chart on meteociel seems weird? the 120 chart has a low SE of greenland, just totally disappears by 144

[BorrisB77]

UKMO 144 chart on meteociel seems weird? the 120 chart has a low SE of greenland, just totally disappears by 144

i think it is getting pulled apart by the regeneration of the blocking high.....

[I remember Atlantic 252]

i think it is getting pulled apart by the regeneration of the blocking high.....

yeah, just seemed a bit quick

[Liam J]

Everyone views the outputs differently and part of that boils down to experience in viewing charts and knowing exactly what to look for without taking operational runs at face value all the time. Given the rather erratic outputs and many solutions on the table where we go from here is by no means as clean cut as people may think. History tells me more often than not that these messy evolutions currently being played out will lead to something rather special, once the models grasp the complete pattern change taking place n the NH. Which is quite out of the ordinary so no wonder we have some large divergence in front of us.

We are all at risk of making wrong judgements here until the pattern is agreed upon within the outputs, use the ensembles more than ever in this situation as many times the OP run is way out of kilter with the set, much like this morning.

According to a few predictions made last week we should now be under the infulence of easterly winds & Scandi high.

[BLAST FROM THE PAST]

UKMO 144 chart on meteociel seems weird? the 120 chart has a low SE of greenland, just totally disappears by 144

Yes it seemed unfeasible to me in such a short space of time, I could see it happening 48-60 hrs later but not within 24. The blocking is seemingly retrogressing fast when it gets going and if it were to go 'wrong' it could get sheered as it moves to out NE/N and then NW and trough slips through to sit over us. I am intirgued by the developments, the potential set up for prolonging this approaching spell, yet I'm not convinced yet. Mind you the potential spell looks far more meaty cold than I thought .... so what do I know.

As per last night, the t144 this morning is perfection IMO...again...lets get it to t24

BFTP

Edited November 24, 2012 by BLAST FROM THE PAST

[Polar Maritime]

The METO update looks very promising..

[VillagePlank]

Concern must be growing for the SE for tomorrow morning, particularly Kent/E Sussex and on the Downs,