Model Output Discussions 06z 04/11/16

[bluearmy]

15 minutes ago, mountain shadow said:

I would caveat that statement, buy adding by the GFS to the end of it.

The ECM has performed very well, particularly the ensembles. The GEFS on the other has and continues to churn out means showing a Northerly when it just isn't going to happen.

As I illustrated last night, the extended have had a fair old fail

[Summer Sun]

The Op is on the mild side of the mean now

The 00z it was on the cold side

[Nouska]

15 minutes ago, Changing Skies said:

Keep the faith, I think the MetO have a tone of confidence, ironically the short-medium range is causing more of a headache, I'm not a fan of this erratic behaviour in model output but this is typical when cold solutions wants to bubble to the surface. I'm fairly convinced there will be no proper cold spell early Dec a northerly snap is all, good if it rocks your boat. In real wintry blasts they're usually the first to pick it up.

Absolutely!

I cannot see what the Met office see but I can see that the forecast strat profile at 30mb is an unusual occurence compared to recent times. A Canadian warming has been a prelude to some good early cold periods including the 'Daddy' of them all.

   

Patience required and a realisation that things have changed a lot with regard to overall atmospheric conditions in the intervening decades.

 

[Iceaxecrampon]

Well - what a turnaround from yesterdays treats  we were spoilt to be honest  - cold embedding in decent frosts and good to see the snow holding on the peaks for November.

[MR EXTREMES]

From what I've seen from the models as we head into December pretty much void of negative nao.

I believe our chance will come if the polar vortex gets disrupted further.

although I'm skeptical of any real Greenland type blocks.

we see vortex building strength this likely to continue through December 

[Jimmyh]

Huge fan of this page, but already beginning to see exhaustion setting in. I have learnt so much in the last few years by reading between the lines and trying not to get hung up on the one liners.

Having been a follower of this for a good few years, here is my take on the model output at moment. The swings are huge. From deep deep cold to mild mush, there is of course a huge difference to this time last year.

This time last year we had absolutely no signs of cold, this year we have a vortex which has been on holiday, unable to decide where it will go for a number of weeks. The feeling I have is that we could be on the cusp of something great or just get caught in no mans land frustrated as cold pools vere into the mid atlantic. I love a good storm, but I am really not seeing where this jet will become mobile in the short term.

Is exciting and I think a chill pill needs to be handed out, if as has been said by we minutely look at each run four by GFS then it is frought with danger.

please don't let the sniping and one upisms get your backs up

 

this could be a hugely exciting winter period     

[Spah1]

UK Outlook for Saturday 10 Dec 2016 to Saturday 24 Dec 2016:

After a wet and windy start to this period, high pressure is likely to dominate from mid December, with fairly 'blocked' conditions becoming established across the UK.

Hopefully this doesn't mean high pressure sat over the UK. We need it to move northwards. 

[jvenge]

19 minutes ago, MR EXTREMES said:

From what I've seen from the models as we head into December pretty much void of negative nao.

I believe our chance will come if the polar vortex gets disrupted further.

although I'm skeptical of any real Greenland type blocks.

we see vortex building strength this likely to continue through December 

GFS is keeping it negative at the moment. ECM has it rising above towards the end of the run, but it hasn't been too consistent with this. ECM also has AO going positive, while the GFS mildly negative.

[captaincroc]

Winters in the UK are like a Tombola.  All the season we put our hands in that bucket, normally the odds are stacked against our favour....firstly we have to get a number ending in a '5' and even if we do, most of the prizes are unwanted Bath Salts. This winter though, things are different. It feels there are a lot more '5's and the prizes this time are epic...let's just hope we get a lucky ticket. 

[cardiff lad]

Been following for a couple of years and enjoy reading different posts and the way the weather changes.its different to last year already rain after rain  enjoying the sunshine today cold wind but dry as I learned get the cold in first and the goods will follow hopefully as it is still autumn.

[Timmytour]

I've come on about this time the last couple of days to posts in awe and wonder after the GFS 6z run only to see expectations firmly temperered and back on the leash after the later ECM and GFS runs.

I'm fully expecting hoping today turns out to be the complete opposite!  :-)

[stainesbloke]

28 minutes ago, Jimmyh said:

Huge fan of this page, but already beginning to see exhaustion setting in. I have learnt so much in the last few years by reading between the lines and trying not to get hung up on the one liners.

Having been a follower of this for a good few years, here is my take on the model output at moment. The swings are huge. From deep deep cold to mild mush, there is of course a huge difference to this time last year.

This time last year we had absolutely no signs of cold, this year we have a vortex which has been on holiday, unable to decide where it will go for a number of weeks. The feeling I have is that we could be on the cusp of something great or just get caught in no mans land frustrated as cold pools vere into the mid atlantic. I love a good storm, but I am really not seeing where this jet will become mobile in the short term.

Is exciting and I think a chill pill needs to be handed out, if as has been said by we minutely look at each run four by GFS then it is frought with danger.

please don't let the sniping and one upisms get your backs up

 

this could be a hugely exciting winter period     

Great post 

Background signals have been consistently pointing to some markedly different conditions this year to previous awful 'winters' which is very interesting in itself. No guarantees of snow but thankfully months of Atlantic ghastliness looks unlikely this year. It is November 25 not February 25 so no reason to be downbeat whatsoever. 

Some very nice early winter weather to come in the next week or so too, with high pressure in charge.

[phil nw.]

The latest London ens graph for 2m temperatures shows a large amount of spread as we start the new month.

Rainfall low which suggests a blocked outlook around the UK,at least for a week seems the likely outcome..

The spread in temperatures probably due to where the high settles,a little further north would allow a colder feed off the continent such as shown for this coming Sun/Mon.

The cold air coming down and around the high from the Scandinavia trough to our east.Mid day temps just above freezing in the south and sub-zero further north.

Beyond the next few days? who knows with such a wide spread of solutions to the NH pattern it's one of those times that a mean chart doesn't show the whole picture and a deeper look at the clusterings in the gefs stamps may give an idea of trends.

Have a look at the gefs for a week today T168hrs

anything from a strong northerly to a UK high is there-more volatility than normal quite early on as underlined in that first graph.

 

.

[Mucka]

Looks like the GFS is ready to wave the white flag on the Northerly if the 06z ensembles are to be believed which is odd given the signal strengthened if anything in the 00z set.

ECM is a good run if you like dry chilly weather with frost but taken at face value it is followed by long draw Southwesterlies and very mild weather. We could muse about the possibility of a Scandi high another week down the road but otherwise it is pretty desperate stuff if we are looking for cold in FI. I suspect we will maintain a more amplifed pattern than that though so doubt it is leading the way to a pattern change.

ECM ensembles have totally moved away from any real cold and mostly go for temps around normal to above normal for early December after a chilly start, A few very mild runs probably reflecting patterns close to the Op but huge scatter and a few chilly runs too so not a lot of information there other than no signal for real cold.

Given all that, it is a case of taking long term forecasts at face value and looking forward to our first cold spell toward mid December that leads into a white Christmas for the optimistic cold weather fans. 

November will end a fairly chilly month and there has been a fair bit of blocking, just mid latitude blocking that never quite set up in the right places for an unseasonably cold blast.

Early December looks like more of the same so we await charts that show the blocking getting into the higher latitudes to enhance our cold prospects.

I kind of hope the phantom northerly is completely put to bed this evening as a break from willing cold and snow charts into reality is needed 

Time for a rest and to come back refreshed to chase down those Winter charts - in actual Winter! 

(We all know this evenings output will probably lure us back in though and we are still in an amplified pattern so something can, and probably will, crop up very quickly )

 

Edited November 25, 2016 by Mucka

[No Balls Like Snow Balls]

And relax................ and SMILE.

A Santa surprise perhaps. 

 

 

Edited November 25, 2016 by No Balls Like Snow Balls

[Blessed Weather]

Yes, we must keep our spirits up! GEFS 11-15 day forecast:

"Northerly flow directed at Scandinavia around main #polarvortex center suggests #cold weather for Northern Europe soon after #winter starts."
Dr. Cohen.

 

[karlos1983]

Very exciting times ahead I feel. 

[SteveB]

Call me crazy, but I still have a feeling the models will start to show a swing back to colder in the next couple of day's

It's not often at 144-168hrs the charts continue showing the same out come down to 0hrs, so there is no reason why they should start now.

I still think a Northerly of sorts will happen sometime next weekend on wards.

The Northern hemisphere is primed differently this year, Polar Vortex is all over the shop & so are the charts.....

BRING ON THE 12z

Edited November 25, 2016 by SteveB

[Ravelin]

5 minutes ago, SteveB said:

Call me crazy, but I still have a feeling the models will start to show a swing back to colder in the next couple of day's

You are crazy!

Then again, so am I probably because I have the niggling feeling that's likely/possible too. Put it this way, nothing will surprise me given the model shenanigans recently.

[festivalking]

Can anyone remember such a week of yo-yo output before this one? Last winter it was obvious relentless mush. Even Dec 2010 was rock solid in its output leading up to it.  It's been extraordinary and I doubt its not over yet. Surprised no one has mention Shannon during the week!

[Methuselah]

3 minutes ago, festivalking said:

Can anyone remember such a week of yo-yo output before this one? Last winter it was obvious relentless mush. Even Dec 2010 was rock solid in its output leading up to it.  It's been extraordinary and I doubt its not over yet. Surprised no one has mention Shannon during the week!

Can't say as I have, TBH...In some ways it's like we've been teleported back into the 1960s, when 3 days' forecasting accuracy was your lot...Long may model-uncertainty continue!

[feb1991blizzard]

4 hours ago, booferking said:

Scandi high me thinks. Building heights towards i mean

I was seeing a distinct upper ridge building in the Atlantic in close proximity -  it suddenly built from a flat scenario in just a few frames on the mean deep into FI, unfortunately it flattened again, if at that range it would have continued to build by 384, that would have been a very strong signal at such range.

[Tamara]

On ‎24‎/‎11‎/‎2016 at 13:08, Tamara said:

 

However, if traction increases to consolidate an eastwards signal in the tropics as consensus modelling, there are continued signs to show that the Pacific favours a ENSO neutral with a +AAM tinge (a winter such as 78/79 is a good parallel here) then stratospheric weakness will be utilised with the Pacific ridge very much a friend in terms of being part of a cross polar stratospheric induced ridge - that is the beginning of a period for snow and ice.

 

Yesterdays post focussed on the downsides behind the less appealing NWP which has been juggling with the much more appealing amplified responses to CW polar stratospheric weakness. On that basis I felt quite complimented by my description of "cautious optimism"

I wonder if the upside angle of todays post might constitute a leap from sanguine caution to wilder abandonment?

Want some of that 'return to Maritimes' forcing traction? Its almost insidious for sure, but first tentative hints of joys to come seeping into the just updated GEFS and ECM tropical convection suites.

 

Is the next angular momentum upsurge coming into view to ramp up amplification/stratospheric weakness to another level and further evidentially support the cross polar profile and those week 3 and 4 decidedly yummy extended ECM profiles? The timing on this could be very fitting....

Based on the fact that the atmospheric circulation remains largely disconnected anyway with a higher atmospheric angular momentum tendency than suggested vs the ENSO base state, then the ante is upping to increase 'upside' to this disconnect prevailing throughout - as lifespan time keeps running out for the expected course of this Nina (the end of the year).

The ECM model is increasingly bullish now in terminating this (disconnected) contract into the heart of winter - and the majority of models are heading more and more towards a shortfall of the Nina threshold and ENSO neutral prevailing over the coming weeks. With AAM already disconnected to the Nina base state, then this neutral trend would may augur better still for sustained atmospheric buoyancy to capitalise on strong Eurasian stratospheric feedbacks courtesy of excellent autumn snow cover and favourable ice weakness over Kara/Barents - and help drive home programmed amplification attacks on the vortex and an -AO/AO profile beyond the New Year. There are dominoes certainly to fall before then, but in a wildcard winter, such a wider abandonment scenario is not beyond my own feasible comprehension - if todays focus switches with more emphasis on possible 'upsides'.

The 30 day moving SOI, right now, up to the last week of November, underpins how much of a departure has occurred over the course of the autumn. The disconnect continues...and with time running out to meet those previous forecast expectations. Something should give quite quickly one way or the other....

 

On daily increasing evidence basis there are at least as much grounds for any Nina-esque Pacific Ridge being the cross polar friend rather than the mid latitude upstream foe I cautioned of yesterday.

The Global Wind Oscillation has already rebounded straight back from quite high amplitude Phase 8 (following the end of the recent MJO cycle) back to Phase 4.  The fall in total GLAAM has been restricted just to parity, after that overstretched +ve disconnect at almost +2SD!

This leaves the atmospheric circulation precisely where it was at the end of October (just ahead of the previous, then imminent tropical forcing spike) and that is in spite of the considerable downward inertia of an atmospheric angular momentum correction (as discussed in recent updates) that balances flux budgets following active tropical cycling through the Pacific

This limited fall, set against ocean base state, is ahead of the return of the IO/Maritime forcing coming slowly into view and which would spike angular momentum positive heading into winter proper and really ramp up the prospects for amplification, taking maximum advantage of that early stratospheric weakness.  On the basis of such a timed spike in AAM, the natural change in seasonal wavelengths heading from December to January would work natural magic on the NH weather patterns seen in other neutral ENSO/+ve GlAAM, solid Eurasian snow cover years

....Heights from southern Greenland, Iceland to Scandinavia - and with the Global Wind Oscillation orbiting in Phases 5/6/7 (as recently) rather than threatening Nina phases 1,2,3. 

The continuing failure for ocean/atmosphere coupling to properly occur against downside pressure, further increases my own suspicions harboured since late summer that, although its still too soon to be absolutely certain, some consensus opinions of both the potential effects and longevity of this event may have been overcooked. 

If, and it is  still an if at the moment, this does prove to be the case then the downside floor (described yesterday and which still exists) of -ve GLAAM/weak Nina, westerly QBO and decreasing solar cycle = increasing threat of stratospheric vortex recovery and +AO/NAO profile pendulum ......swings more and more the other way to  +ve inclined GLAAM/neutral ENSO constructively augmenting sea ice, SIA and SCE feedbacks  = potential for Jan SSW.  

That would beat a drum as icing on the cake for mid winter prospects

 I really shouldn't get ahead of myself, but I have nevertheless indulged regardless.

..

[london-snow]

1 hour ago, No Balls Like Snow Balls said:

And relax................ and SMILE.

A Santa surprise perhaps. 

 

 

Although encouraging can't help but feel everything's getting shunned further and further back.

[bradymk]

1 hour ago, No Balls Like Snow Balls said:

And relax................ and SMILE.

A Santa surprise perhaps. 

 

 

Looks like ecmwf seeing an easterly flow weeks 3 and getting stronger week 4 then judging by those temperature charts. Haven't seen any 500hpa anomaly charts yet. Shame it's still 3 weeks away but like I said last night, would still rather it be showing the cold outcome it is rather than mild anomalies regardless of how unreliable it's been or how far away it is.