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Model Output Discussions 12z 30/11/16


phil nw.

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Posted
  • Location: St rads Dover
  • Weather Preferences: Snow, T Storms.
  • Location: St rads Dover
11 minutes ago, booferking said:

A few ENS show a slight glimmer of hope around 8th 9th Dec, fingers crossed this trend can pick up

gensnh-15-1-180.png

gensnh-7-1-180.png

gensnh-13-1-192.png

gensnh-15-1-192.png

TBH the top chart is kind of the way I expected things to go, the high being push NW by the Atlantic going under, and the east pushing in. Looks like the opportunity may still be there.

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Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
15 minutes ago, booferking said:

A few ENS show a slight glimmer of hope around 8th 9th Dec, fingers crossed this trend can pick up

gensnh-15-1-180.png

gensnh-7-1-180.png

gensnh-13-1-192.png

gensnh-15-1-192.png

this was a theme in the ensembles a couple of days ago - got a bit lost yesterday - the ECM ensembles at D15 has hints of this too

ec-ens_nat_gh500mean_gh500std_thk500mean

 

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Posted
  • Location: Lytchett Matravers - 301 ft ASL
  • Weather Preferences: Snowy Winters, Torrential Storm Summers
  • Location: Lytchett Matravers - 301 ft ASL

Again, I've seen a lot lot worse! 

IMG_3805.GIF

Next weeks mild blip aside that is. Trends the right direction after that, to chilly at worst.

Edited by karlos1983
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Posted
  • Location: Essex, Southend-On-Sea
  • Weather Preferences: Warm, bright summers and Cold, snowy winters
  • Location: Essex, Southend-On-Sea
7 minutes ago, Man With Beard said:

With respect that's exactly what I said above and I did actually check the very chart you're showing before I posted - there is a height anomaly to the NW and so I accept the ECM46 was right to a degree on a macro-scale, but I believe we were expecting high pressure to the NW - I mean, much further NW than what we see below - and because the ECM46 didn't get the micro-scale right, conditions ended up extremely differently to the general interpretation people were making in early November, and so to the man on the street it would be seen as being wrong.

gfs-0-6.png?6

Now the argument will be "Why are people expecting a D30/D40 forecast to predict the micro-scale details so precisely in the first place?" But that's the whole point. If it can't, then more caution is needed. I know some show caution already, but I think it is not enough. Just how many times has "Wait until mid-December" been mentioned on here this week - giving a rather stronger impression of certainty than is helpful???

Micro-scale isn't what the LRF models are made for. So when it comes up with height rises NW there is an increased chance of a cold outbreak but doesn't guarantee it. It is a case of us getting ahead of ourselves, when caution was heavily advised we took what we wanted to hear and forgot the rest despite the chances of mild still being there. 

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Posted
  • Location: Lincolnshire - 15m asl
  • Weather Preferences: Frost and snow. A quiet autumn day is also good.
  • Location: Lincolnshire - 15m asl
2 hours ago, Tamara said:

Other than the adjustments in timetable as reflected by the major weather organisations, it doesn't change the bigger picture outlook as laid out yesterday. Its a case of monitoring those feedback loops - there is a lot going on over Siberia and to the NE to watch, just for starters. Plus the tropical interference in the I/O is not a seasonal permanence!

.

Thanks Tamara - i think this is key. Timetable not destination...

I'm wondering where you are seeing things longer term. Downward propagation of an unhappy vortex looks to me to be a two week task, and then perhaps we get a sustained imprint of that disrupted pattern on the troposphere, backed up by timely reamplification in the pacific. Cold from second half December through into the New Year if the blocks set up in the right place, accounting for rinse and repeat nature of a blocking pattern. But what about beyond that? Dare I pick your brains on it?

With the upper vortex looking to recover through the month from a starting position over Siberia where do we go? If Cohen's view is correct then low sea ice and early snow cover will encourage HP development in the Kara region and we can expect a degree of strat warming to persist from this direction. But what about over in the Pacific? Do you see a neutral ENSO pattern allowing more wave breaking from the aleutian low, or will that pattern fade and a more blocked pattern also emerge over the north pacific? Is Nina dead and buried as a threat?

The holy grail would surely be a wave 2 attack riding on the back of a delayed MJO progression as hinted at now. This might delay our winter start, but lead to a greater peak in cold potential from mid January through into February following on from a blocked beginning in December. Sounds like Nirvana to me. Time scales would then suggest perhaps a more mobile second half of February?

Or do you think we will see a changed Pacific profile,, perhaps only wave 1 working from the Siberian side to re position the vortex over Canada/Greenland and a consequent shift towards a more mobile pattern in the second half of winter?

Ha - lots of questions. But worth chewing over while we wait for the current model output to see more clearly what is going to happen mid month. Watching a block sink into Europe with milder air coming up from the SW running over the top is about as much fun as sewing on name tapes.

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

Lots of zig-zagging and no flatliners on yet another very poor GEFS suite, ECM ensembles certainly trending the right way at the end though.

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Posted
  • Location: Newton Poppleford, Devon, UK
  • Weather Preferences: Snow, Thunderstorms, High Winds.
  • Location: Newton Poppleford, Devon, UK

The GFS, ECMWF and UKMO model all show the Atlantic taking hold.

gfs-0-114.png?6 gfs-0-138.png?6

ECM1-120.GIF?02-12 ECM1-144.GIF?02-12

UW120-21.GIF?02-06 UW144-21.GIF?02-06

Edited by Grimers
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Posted
  • Location: Brighton, East Sussex
  • Location: Brighton, East Sussex
17 minutes ago, Grimers said:

The GFS, ECMWF and UKMO model all show the Atlantic taking hold.

gfs-0-114.png?6 gfs-0-138.png?6

ECM1-120.GIF?02-12 ECM1-144.GIF?02-12

UW120-21.GIF?02-06 UW144-21.GIF?02-06

With all due respect, those charts dont show 'the Atlantic taking hold' really, Atlantic influence yes but primarily the slug high pressure block is in charge and looks like remaining so for the foreseeable.

I know it's the old cliche on here but in my opinion we need a reset in the pattern, unfortunately it looks like it could be hard to shift.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
19 minutes ago, Grimers said:

The GFS, ECMWF and UKMO model all show the Atlantic taking hold.

gfs-0-114.png?6 gfs-0-138.png?6

ECM1-120.GIF?02-12 ECM1-144.GIF?02-12

UW120-21.GIF?02-06 UW144-21.GIF?02-06

Yes there is no gain without some pain, it looks certain that next week will become much milder.

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Posted
  • Location: Surrey and SW France.
  • Location: Surrey and SW France.

Kara sea blocking high is a response to good early snow cover and low ice in the region - yep - fine example of this in action for the first ten days of January 2016!

psnh_jun_hist_z500_201601.gif

Was this not the very thorn in the side of expected improvements in the outlook last year?

As an aside, a good example of how seeing this chart as an anomaly forecast might not tell the full story.

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Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
2 minutes ago, Nouska said:

Kara sea blocking high is a response to good early snow cover and low ice in the region - yep - fine example of this in action for the first ten days of January 2016!

psnh_jun_hist_z500_201601.gif

Was this not the very thorn in the side of expected improvements in the outlook last year?

As an aside, a good example of how seeing this chart as an anomaly forecast might not tell the full story.

Trough anchored to the West of us giving warm and very wet weather.

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Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL
5 minutes ago, feb1991blizzard said:

Trough anchored to the West of us giving warm and very wet weather.

Depends really, if the Heights can move Westwards a wee bit it could open up some interesting battleground situations. 

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Posted
  • Location: Heckmondwike, West Yorkshire
  • Location: Heckmondwike, West Yorkshire
8 minutes ago, Nouska said:

Kara sea blocking high is a response to good early snow cover and low ice in the region - yep - fine example of this in action for the first ten days of January 2016!

psnh_jun_hist_z500_201601.gif

Was this not the very thorn in the side of expected improvements in the outlook last year?

As an aside, a good example of how seeing this chart as an anomaly forecast might not tell the full story.

Good post. In theory it seems good for us to have the Kara block but in practice it does indeed look like a thorn in the UK winter!

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Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL
36 minutes ago, Grimers said:

The GFS, ECMWF and UKMO model all show the Atlantic taking hold.

 

Not one of those show the Atlantic taking hold. Those show the Euro slug High taking hold.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North

The Gefs 6z mean shows mild swly winds locking in from next midweek onwards and gradually becoming more changeable with bands of rain interspersed with brighter, showery conditions but with some fine spells too. Further ahead becomes more unsettled and perhaps not as mild with some cooler atlantic air into the mix.

21_120_850tmp.png

21_144_850tmp.png

21_168_850tmp.png

21_216_850tmp.png

21_216_500mb.png

21_240_500mb.png

21_240_850tmp.png

21_288_500mb.png

21_336_500mb.png

21_384_850tmp.png

Edited by Frosty.
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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
7 minutes ago, mountain shadow said:

Not one of those show the Atlantic taking hold. Those show the Euro slug High taking hold.

The Atlantic takes hold eventually according to the Gefs 6z..positive NAO

Edited by Frosty.
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Posted
  • Location: sheffield
  • Weather Preferences: cold ,snow
  • Location: sheffield
6 minutes ago, Frosty. said:

The Gefs 6z mean shows mild swly winds locking in from next midweek onwards and gradually becoming more changeable with bands of rain interspersed with brighter, showery conditions but with some fine spells too. Further ahead becomes more unsettled and perhaps not as mild with some cooler atlantic air into the mix.

Yes becoming more unsettled for sure.Cooling of later on the run so pretty average December weather tbh.Still prefer the dry frosty weather but i guess we are due some unsettled and disturbed stuff

Edited by swfc
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Posted
  • Location: Surrey and SW France.
  • Location: Surrey and SW France.
2 hours ago, Man With Beard said:

But how useful are they if they change so much?

Last night I listed some of the successes that Glossea has had recently (we know thanks to Fergie's updates). But can anyone tell me of a reasonably successful D20-D46 forecast from the ECM 46 in the past year - apart from when it is predicting westerlies?

I don't know about that but it is all here - for two years - if anyone wants to have a look.

http://www.ecmwf.int/en/forecasts/charts/mofc_multi/mofc_multi_verification_anomaly_family_vanomaly?time=2016111400,0,2016111400&parameter=2m temperature&area=Europe

Z500 ...

http://www.ecmwf.int/en/forecasts/charts/mofc_multi/mofc_multi_verification_anomaly_family_flowz500?time=2016111400,0,2016111400

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

Yes, almost certainly a zonal second half of Dec now, it may be drier towards the SE and temps depending on jet angle but mildish looming.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
1 minute ago, SN0WM4N said:

This posts adds nothing to this thread apart from knee-jerk reactions.

That's not true, it's what the GEFS 6z mean is showing!

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Posted
  • Location: Leeds
  • Weather Preferences: Bitter Cold in winter and Extreme heat in summer
  • Location: Leeds

Yes very confusing for new members like me.

As after reading the latest MO update it's still favouring cold/blocked. 

 

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