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Model output discussion - is the beast awakening?


Paul

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Posted
  • Location: Banbury
  • Weather Preferences: Deep Deep Snow causing chaos
  • Location: Banbury
9 minutes ago, sheikhy said:

As i say if the ecm does not improve on the 00z its game over!!nobody will like what im saying but ive seen this happen plenty of times over the years and more often than not there is no going back!!i can call this now but i wont i will give the ecm a chance till the 00z!!!you can have all the ensemble backing you want but the op is very good at picking out a change and those ensembles will follow in the end!!!yes 1 op run does seem to go wrong and then improve straightaway the next run and we better hope this is one of those times!!!anyway enjoy whatever snow we get between now and tuesday lol!

I have also been taken right up the garden path by ECM as well  , so you are saying if ECM isn't showing it then it aint going to happen 

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Posted
  • Location: Rotherhithe, 5.8M ASL
  • Location: Rotherhithe, 5.8M ASL
1 minute ago, Battleground Snow said:

That's doesn't look too bad at 216 with lowish heights near Italy.

I don’t think it’s a catastrophic shift from this morning it does look ECM op was off far too progressive with getting low heights in scandi, but not what we want to see continue from either, the low heights to southeast are very important we need them further east otherwise you get a soggy bottom and Scandi high will sink quickly! 

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Posted
  • Location: Near Gouda, Holland. 6m Below Sea Level.
  • Weather Preferences: Sun, snow, ice. Very hot or very cold.
  • Location: Near Gouda, Holland. 6m Below Sea Level.
7 minutes ago, Daniel* said:

Definitely not as bad as OP but worse than this morning heights to NE gain less latitude and higher pressure in med which makes it difficult to draw coldest air in.

4D88051B-184E-4CBC-99DE-CBAC5C531C77.thumb.png.8e90dbcc871df1df6560bc5d74585bf4.pngF4CDA9BE-8E94-402B-ABEF-256095D0471A.thumb.png.814f3d6f857c0a83e68bf1fd794d3dc5.png

That goes hand in hand.

A solid Scandinavian High, a dynamic high that is, causes lower pressure over Europe.
If it does not develop, or in a flabby way, it doesn't succeed in lowering those S-European/Mediterranean Heights.

It's a pity that this seems to be a bit of a downgrade.
No desperation though. We've been here before. I've never seen a cold spell arrive without drama.

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Posted
  • Location: Essex Riviera aka Burnham
  • Weather Preferences: 30 Degrees of pure British Celsius
  • Location: Essex Riviera aka Burnham

ECM and UKMO make far less of heights at D6 around Greenland compared to GFS...I wonder if this could be an issue?

Can't make head or tail of tonight's ECM 12z after D6 it's anybody's guess.

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Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.
1 minute ago, sheikhy said:

Fair enough!!!just beware this one run could change the whole dynamics!!!i want it to get back to what it was showing just as much as you mate!!fingers crossed!!

It's one single run of a computerised mathematical simulation; there's no way in which a computer model can effect changes in the dynamics, of the weather...?

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Posted
  • Location: Essex Riviera aka Burnham
  • Weather Preferences: 30 Degrees of pure British Celsius
  • Location: Essex Riviera aka Burnham
2 minutes ago, MJB said:

so you are saying if ECM isn't showing it then it aint going to happen

More chance of that happening than if it was the GFS not showing the blocking.

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Posted
  • Location: Bath, Oxford
  • Weather Preferences: Cold and snowy winters, hot and sunny summers with thunderstorms!
  • Location: Bath, Oxford
14 minutes ago, sheikhy said:

As i say if the ecm does not improve on the 00z its game over!!nobody will like what im saying but ive seen this happen plenty of times over the years and more often than not there is no going back!!i can call this now but i wont i will give the ecm a chance till the 00z!!!you can have all the ensemble backing you want but the op is very good at picking out a change and those ensembles will follow in the end!!!yes 1 op run does seem to go wrong and then improve straightaway the next run and we better hope this is one of those times!!!anyway enjoy whatever snow we get between now and tuesday lol!

It's not "game over"? Look at the bigger picture instead of taking at each run at face value. The signals can reappear as quick as they disappear.

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Posted
  • Location: Maldon, Essex
  • Location: Maldon, Essex

It’s the same thing every time. Amazing charts in FI, and people fall for it every time!

I would wait until the morning, but downgrades never seem to reverse.

ECM ensembles may give us more of a clue on where this is heading 

 

 

Edited by Djdazzle
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Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon

Away for most of the 12z rollout on weekly pub replacement Zoom call with mates.

And pages to read.  

So i take it the UKMO is OK as far as it goes, the GFS not as good as 6z, but sort of gets there, the // a bit better and delivers in FI, the ECM is dreadful.  Sounds like standard flip flopping in a situation with high uncertainty.  We won’t sort this until Sunday at the earliest.  And there’s possible snow for many on Saturday.  Apparently low heights in Genoa are essential, I always thought that was a cherry cake that had failed to rise in the tin.  

ECM mean T240 compared with 0z:

53EB2260-DC1A-4059-B0ED-D8080343D5BD.thumb.png.af53001aa1310d146b71f8ae15fb915d.pngB141B82D-9280-4CB6-8FAE-DCC9ED5B0A14.thumb.png.669187a0df771bcfbf46017fd42068d4.png

It does look a bit worse, but might be only a few moire members going rogue, we will see..

 

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Posted
  • Location: Banbury
  • Weather Preferences: Deep Deep Snow causing chaos
  • Location: Banbury
8 minutes ago, Froze were the Days said:

More chance of that happening than if it was the GFS not showing the blocking.

And you have evidence of that ? 

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Posted
  • Location: Dead Centre of the Vale of Clwyd
  • Weather Preferences: Cold Sancerre.
  • Location: Dead Centre of the Vale of Clwyd
6 minutes ago, Djdazzle said:

It’s the same thing every time. Amazing charts in FI, and people fall for it every time!

I would wait until the morning, but downgrades never seem to reverse.

ECM ensembles may give us more of a clue on where this is heading 

 

 

Pretty much the last 7 days 00Z 'downgrades' have been reversed by the 12Z runs. Generalisation of course, but....

 

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Posted
  • Location: Leicester
  • Location: Leicester
12 minutes ago, MJB said:

I have also been taken right up the garden path by ECM as well  , so you are saying if ECM isn't showing it then it aint going to happen 

COULD still change on the next run of course!!!but it has to change next run mate or it really aint looking good!!!for me ecm has always been the top model since the early days when i first started on here!!!like i mentioned earlier i want it to change for the better just as much as anyone here!!

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Posted
  • Location: Leicester
  • Location: Leicester
12 minutes ago, General Cluster said:

It's one single run of a computerised mathematical simulation; there's no way in which a computer model can effect changes in the dynamics, of the weather...?

You know what i mean!!!!anyway ecm gota change in the morning!!

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Posted
  • Location: East Ham, London
  • Location: East Ham, London

Evening all

A decent day in lowland East London despite a few morning showers but colder through the afternoon. 

I didn't view last evening's models with the euphoria of some others - the journey to something colder next weekend seems there albeit far from certain (even at T+180) but the severity and longevity of any cold spell or snap far from certain. GFS, which seems to run the atmosphere on steroids, quickly returned Atlantic dominance while Parallel gave us a nice warm E'ly (believe it or not) while ECM just went off on one of its improbable T+216 and T+240 evolutions.

Clarity is much needed but I suspect it won't be found on today's wibblings but we'll see:

12Z GEM: T+120 takes us to Wednesday February 3rd at which time the Atlantic trough is moving across southern Britain with E'ly winds over Scotland and a cyclonic flow further south. Heights to the east of Iceland and upstream amplification ahead of a new storm moving off the eastern seaboard. Mild air with positive uppers persists in the south but it's colder further north with -4 to -8 850s generally and uppers below -8 over northern Scotland. From there, heights rise over the British Isles as a wedge of HP develops by T+180 from the Azores, through the British Isles to Scandinavia. A new Atlantic trough has formed from a lobe of energy off the storm over North America and has moved quickly NE to be near Iceland by T+180.  A broad but shallow trough sits over Europe. The colder air mass has moved south with 850s below -8 over much of southern Britain and -12 uppers close to the east coast. Uppers of -4 to -8 elsewhere. Moving on, and the Atlantic LP spins to the north of Iceland, turns east and then south east as heights rise to the far north and by T+240 is moving SE into the North Sea. It is phasing with the residual LP over the Balkans. A wedge of heights persists from the Azores towards south-west Britain. Milder air has pushed back into western and south western areas but it remains colder to the east with a new wedge of colder air coming into Scotland behind the LP.

image.thumb.png.ab6bee120ef82efe6750ed5d833ffe84.pngimage.thumb.png.91df9e033a9c5223aa84d0379d92e59f.pngimage.thumb.png.ae521c02e98e5ee8b2a8afa3ddd73cc3.png

A complex and messy evolution from GEM to be honest.

12Z GFS OP - at T+120 a complex trough covers southern and western Britain with centres over southern England and to the north west of Ireland and a third feature just to the north east of the Azores. Heights to the north and upstream amplification. 850s over the British Isles either side of zero at this time with the coldest air confined to the far north of Scotland and the northern isles. From there, heights continue to build to the north and the trough slowly fills and sinks south and by T+180 the British Isles in an ESE'ly air flow with 850s zero to -4 over southern areas and below -8 for much of northern Britain. Moving on and the E''y air flow persists but the heights are weakening to the north and the Atlantic trough has moved SE and is now starting to pivot back to a more positive alignment which will lead to heights rising again over southern Europe so I suspect the Atlantic reset is coming. At T+240, the cold regime is holding on with 850s generally below -8.

image.thumb.png.e973b8953ba648a8b48697800ebbb068.pngimage.thumb.png.c424d637317a31b443b58e38b9b93621.pngimage.thumb.png.f42b4cc3ae968f6730408b323980ce85.png

12Z Parallel - at T+120 the profile is similar to the OP with the controlling LP over North-west Ireland and a cyclonic SSE'ly flow over the British isles with heights to the north and upstream amplification - weak heights over Scandinavia at this time. Milder air with positive uppers over southern Britain but colder air persists over northern and eastern Scotland and the Northern Isles. From there, as with the OP, heights build strongly to the north and the trough fills and sinks south leaving an E'ly air flow over the British Isles. Uppers below -8 covering much of the British Isles by T+180 (Saturday February 6th). From there, the E'ly persists across southern parts as the HP relaxes slightly north west. Despite the continued air flow direction, the air source is further south so some milder air comes into the mix leaving uppers at T+240 zero to -4 over south east England and -4 to -8 elsewhere.

image.thumb.png.50722f28acbb9f06b771adfd9f0448a2.pngimage.thumb.png.ac02bd1dab768b51abaeb4809d441caf.pngimage.thumb.png.c9605ff7dd633f3b202e20c814eb9b26.png

Parallel loves its mild easterlies, doesn't it?

12Z ECM - the evolution was a real curiousity last night especially post T+192. At T+120 tonight, the trough orientation is slightly different to other models but we have heights to the north and upstream amplification. Uppers either side of zero over most of the British Isles but colder air with uppers of -4 to -8 persist over Northern Scotland. From there, the Atlantic storm which is just coming off the eastern seaboard at T+120 races north east to be just off Norway by T+192 with a second LP to the south of Iceland. HP over the Azores persists along with heights which were over Scandinavia and have already sunk south-east into Europe. Milder uppers approaching from the west but colder air persisting over eastern areas by T+192. Moving on, the trough splits - one element sinks south to the west of Ireland while the other starts to sink SE through Scandinavia with a moribund Atlantic and heights building through Iceland leaving a slack N'ly over the British Isles by T+240. Much colder air has moved south with uppers below -4 for most places and below -8 over Scotland.

image.thumb.png.18944273910d5c68b92d683b978d2cf9.png image.thumb.png.9656cca0145152ebaa8681c5d09b2416.pngimage.thumb.png.f387fe05a0abdf610c320fd88891d8be.png

Nope, don't buy that ECM evolution at all - it's a model drowning in its own data contradictions.

 Looking further ahead, GFS OP and Parallel at T+312 (February 11th) and T+384 (February 14th) respectively:

image.thumb.png.30ba98ca49ba462f6c5d3c3786cb592e.pngimage.thumb.png.202ed43f46d0aee5ab90b19c1143105c.png

image.thumb.png.28bf907a8b71507bb2adc1f7738747c4.pngimage.thumb.png.3326fd9378e9824a7ea1889484297eb1.png

OP blows up a huge mid-Atlantic trough which breaks down the cold spell while Parallel is a coldie's nirvana with Easterlies and Northerlies throughout FI and a solid 10 day cold spell. After last night's horror show, Control is mostly cold or very cold and ends with a battleground.

The 10 HPA suggest a new warming trend approaching mid-February but that's a long way off.

Conclusion: while I don't really accept the evolution, ECM and GEM get to cold in the end - it's rather simpler with GFS OP and Parallel with the trough filling and disrupting south as heights build from the north. OP breaks down the cold spell quite quickly while Parallel is superb for coldies (Control not bad either). ECM does strange things with an Atlantic trough which seem to defy the laws of physics. NAVGEM and JMA are different again so the amount of uncertainty post T+180 is a concern - we can but hope Parallel has called this well. I just don't see how, in the absence of a strong PV and zonal jet we can be seeing a robust Atlantic - but some models want t push an Atlantic trough NE toward Iceland to break down the mid-Atlantic amplification so we'll see.

 

 

 

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Posted
  • Location: st albans
  • Location: st albans

The models seem to have lost their satnav ... all become a bit of a mess after seeming to be converging on a broad solution yesterday

the eps suite has six mainly even clusters in the 8/10 day period - no getting away from the slow drift away from deep cold 

the gefs were a bit of a curates egg too 

suggest some deep breaths and see what the 00z bring 

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Posted
  • Location: Leicester Forest East (Leicestershire)
  • Weather Preferences: Hot and dry in summer and cold and snowy in winter
  • Location: Leicester Forest East (Leicestershire)
31 minutes ago, sheikhy said:

Mate one day they lookk darn good and next update theyre not good at all

A sheiky post without exclamation marks

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Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon

It seems to me that there are two phases to this evolution necessary to get the real cold air to our shores properly. 

The first is some proper connection between the block and the Arctic high.  This is shown on GFS (and also //) at T144:

726678EE-B41C-4240-A569-5CC24D9DA6E4.thumb.jpeg.9d0429f1364477b61ae3711569ce2a2c.jpeg

The 1030 hPa isobar shown by the yellow line, means advection of cold on a long draw NE’ly.  

ECM just doesn’t have this at same time:

790F6B3B-C748-43CB-9E2B-0927D12794AB.thumb.jpeg.f58ebf57e11640bf6278d37d405e76b0.jpeg

The second phase would be concentrating on the block closer to us (forget the arctic high at this point) to be optimally aligned to bring the cold in to the UK with sufficient disturbances in the flow to cause snow.  No charts on that is it is so uncertain.  Let’s get the first phase sorted, and that means the block has to be more northern than ECM shows.  

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Posted
  • Location: Crewe, Cheshire
  • Weather Preferences: Snow, storms and other extremes
  • Location: Crewe, Cheshire
1 minute ago, Mike Poole said:

It seems to me that there are two phases to this evolution necessary to get the real cold air to our shores properly. 

The first is some proper connection between the block and the Arctic high.  This is shown on GFS (and also //) at T144:

726678EE-B41C-4240-A569-5CC24D9DA6E4.thumb.jpeg.9d0429f1364477b61ae3711569ce2a2c.jpeg

The 1030 hPa isobar shown by the yellow line, means advection of cold on a long draw NE’ly.  

ECM just doesn’t have this at same time:

790F6B3B-C748-43CB-9E2B-0927D12794AB.thumb.jpeg.f58ebf57e11640bf6278d37d405e76b0.jpeg

The second phase would be concentrating on the block closer to us (forget the arctic high at this point) to be optimally aligned to bring the cold in to the UK with sufficient disturbances in the flow to cause snow.  No charts on that is it is so uncertain.  Let’s get the first phase sorted, and that means the block has to be more northern than ECM shows.  

Yes and those Arctic heights were downgraded on the 12z GEFS too, by comparison to the 6z suite.

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Posted
  • Location: NR Worthing SE Coast
  • Location: NR Worthing SE Coast

Ecm always seems to flip-flop around after 144 hours,it maybe the top model up to that timeframe,but after that  its utterly hopeless,worse than gfs,might as well scrap its output after 6 days,impossible to make any forecast from it!

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Posted
  • Location: East Ham, London
  • Location: East Ham, London
2 minutes ago, bluearmy said:

The models seem to have lost their satnav ... all become a bit of a mess after seeming to be converging on a broad solution yesterday

the eps suite has six mainly even clusters in the 8/10 day period - no getting away from the slow drift away from deep cold 

the gefs were a bit of a curates egg too 

suggest some deep breaths and see what the 00z bring 

I'm clearly in a minority of one here - I don't get all the doom and gloom but then I only look at one set of runs a day - the 12s.

ECM isn't the disaster some claim - the 850s at T+240 are decent and you wouldn't argue against another E'ly from that.

GFS OP is okay but the writing is on the wall if you believe the Atlantic is going to produce such a huge and complex trough in the current atmospheric environment and the Parallel is superb for cold fans. 

I haven't gone through the Ensembles but I find with ECM with 50 members plus Control and OP it's a case of, as the song had it "All Kinds of Everything".

The final observation is for snow fans it's not a question of deep cold but of marginal battleground situations going the right way as cold and warm airmasses collide. The frequency of these collisions define what some see as a "snowy" winter even if it's not a particularly cold one and you can have a month of battleground scenarios whereas a couple of days of -12 850s is a rarity and may not produce a flake.

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Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.

Must admit i was probably about 4 more GEFS and 2 more EPS suites of solidity away from calling this nailed, has it fallen practically at the last point it could possibly do so using my ensemble methods?, the one thing that did set the alarm bells ringing this morning was difference in the GEFS 0z mean and eps mean at 240, although both ended well in terms of majority clusters going cold-severely cold, the differences in how were striking plus GEFS over last day have flipped about, still all good apart from downgrading the longjevity on todays 12z, they were positioning the mean ridge very differently run to run around 216-240.

Edited by feb1991blizzard
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Posted
  • Location: Crewe, Cheshire
  • Weather Preferences: Snow, storms and other extremes
  • Location: Crewe, Cheshire
4 minutes ago, stodge said:

I'm clearly in a minority of one here - I don't get all the doom and gloom but then I only look at one set of runs a day - the 12s.

ECM isn't the disaster some claim - the 850s at T+240 are decent and you wouldn't argue against another E'ly from that.

GFS OP is okay but the writing is on the wall if you believe the Atlantic is going to produce such a huge and complex trough in the current atmospheric environment and the Parallel is superb for cold fans. 

I haven't gone through the Ensembles but I find with ECM with 50 members plus Control and OP it's a case of, as the song had it "All Kinds of Everything".

The final observation is for snow fans it's not a question of deep cold but of marginal battleground situations going the right way as cold and warm airmasses collide. The frequency of these collisions define what some see as a "snowy" winter even if it's not a particularly cold one and you can have a month of battleground scenarios whereas a couple of days of -12 850s is a rarity and may not produce a flake.

Of course it's about deep cold. You're not going to get long lasting laying snow in Feb with a marginal set up. It's fine if you want falling snow and a couple of slushy deposits, but nothing more than that.

I'd like to get out there and walk in crunchy snow. Not once have I had the chance to do that this year due to any falls melting almost immediately.

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Posted
  • Location: South Staffordshire
  • Weather Preferences: Snow
  • Location: South Staffordshire

Good grief. 

That ECM isn't a 'downgrade' - it's a complete bipolar opposite that leaves us heading towards mid February and beyond into the dregs of winter with no nationwide snowy spell. It's all fine to say 'it could be an outlier' and lets see what happens next, of course that's very true but that kind of attitude would lead you to believe 'waiting' this winter would have delivered a memorable spell, but it hasn't.

As it is, the models continue to point at the Netweather model thread and shout 'suckers' every time. Couple of good runs deep into FI and the thread explodes with sledges and snowball fights, how do people not learn?!

Still, it doesn't surprise me - this was always a 'close' set up and one that could go either way, it was also at Day 8 still (obviously still FI) and tonight just goes to show that 1 thing in the wrong place ruins an entire set up. GEFS and EPS trending away this evening, it all feels rather 'another one bites the dust' doesn't it? Let's also point out that this is another scenario where ENS all heading in one direction mean absolutely nothing and in potentially colder setups, rarely ever will (unless it's the Atlantic heading in).

It will be interesting to see what the 0z's do with that Energy towards Greenland as this is huge in deciding what happens going forward.

Could just be me and with everything that's going on, but this is starting to feel like the longest few months of model watching in history. I just can't see it 'happening' this year. The much beloved background signals are in our favour, but have been for 8-10 weeks now without delivering. It's just not coming together this season and IMO, won't do either. 

Still, let's see what the 18z and then early suites deliver. Perhaps this will just be a rogue run, I'd put my mortgage on the fact it's on to a new trend and we won't see any sort of easterly next weekend....hopefully I'm wrong though.

PS - How over-reactionary are the MO with warnings since the failings of last weekend?! Complete flop of a forecast area for tomorrow and to have warnings out for 3 days next week in a vast area seems like madness! They will be withdrawn sharpish. 

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