Model Output Discussion 19th January 2014-18z onwards.

[Joe Levy]

I have only just woken up this morning and made the mistake of reading the forum before checking the models. I was confused and expecting to be disappointed based on a couple of posts, and then found the ECM ensemble charts with 850temps like these:

How could anyone say that this is rubbish for cold?! Aside from that, some great posts this morning as well

[NorthYorksWeather]

Full GFS 6Z ensembles for my area ( sorry for IMBYism ). Op run close to the mean generally however we would like to see a nudge colder towards the Control run as this is a beast in the short/long term.

 

[Panayiotis]

As somebody who was always open to the view that the Atlantic might not just barge its way in as originally forecast, I do wonder what the implications are based on the present weather, not exactly going to plan right now as far as I can see.

 

240114 1000GMT NW v6 radar.png

 

In my experience, what the current picture suggests is that the block is far stronger than anticipated at this stage and the route to cold may well come earlier than expected. Just check the latest radar and satellite imagery and it appears to me at least, that the precipitation is much lighter and taking an entirely different trajectory out of the UK, seemingly passing away ESE'wards away from our shores. How this ongoing trend effects the weekend's events will be fascinating to watch and I firmly expect a quite different setup into next week as a result, IMHO there will be changes to the UKMO forecasts in the shorter-term. Whether I'm correct, time will tell and anybody with some insight please tell me if I am way off the mark.

 

Below are the expected movements of the rainbands and associated fronts over the coming 24 hours, firstly the latest analysis followed by one 24 hours later, courtesy of the Fax Charts.

 

240114 MetO Fax Chart - current time.png240114 MetO Fax Chart - t+24.png

 

Hopefully things will change for the better given how the flooding issues are seemingly never ending and a change in weather type must be most welcomed by many.

Top back this up:

http://www.bbc.co.uk/weather/2653822

Click on the video. 

However the Euro4 models had this for 12pm and then increase the PPN later at 6pm:

Edited January 24, 2014 by Panayiotis

[Catacol]

Hi Catacol-

 

I think your wrong, especially when using a 240 chart to support the snow that comes at 168/192 & 216.- seems odd you choose a non representative chart to support your theory

 

However using the stratosphere via the ECM as a forecasting tool for the troposphere at day 8/9/10 & then micro managing that to the UK is less than pointless.

 

Even at the far out reaches of the ECM at 168 /192 /216 on the ECM let say they were to verify

http://www.meteociel.fr/modeles/ecmwf/runs/2014012400/ECU1-168.GIF?24-12

http://www.meteociel.fr/modeles/ecmwf/runs/2014012400/ECU1-192.GIF?24-12

http://www.meteociel.fr/modeles/ecmwf/runs/2014012400/ECU1-216.GIF?24-12

 

The uppers covering the 72 hours are at their HEIGHT around 192 when the -1c isotherm gets into the extreme south, so for there possibility of back to rain, but away from there its all snow im afraid.

 

As semi proof of this- go to the operational run temps above ^^ note the -6c temp on the operational at the end- its reacting to snow cover for the T2M ... it would do this if it was indicating no snow.

 

 

S

OK - just one more post. :-)

 

Steve - I love your analysis on here. You brighten my day every day - and that is reason enough for you to be given a badge of honour on this forum. I love reading of the possibilities of trop model variance and how you are able to see future paths that few on here - myself included - can spot.

 

My own research has found me spending less time looking at trop detailed forecasts and much more time looking at background signals. That must just be my mindset and probably evidence of an inability to grasp all the complexities of the metereological pattern. But it has its merits, and I find myself about 10 years on from starting to learn a bit about all this much more able to pick a pattern than I ever used to be.

 

And what I see is saying - close... but no cigar.

 

So we must agree to disagree on the next 7 - 10 days. But I honestly hope you are right!! Will certainly make for a very interesting week of model watching... that's for sure.

[SMU]

someone post the ECM snowcover charts please from weather bell --- that may support.

 

Snowman- its almost impossible to speculate-

 

maybe south of london 

Edited January 24, 2014 by Steve Murr

[R.P. McMurphy]

Let's try to remember there is room for all views in here and certainly no need for name calling....agree re it being something that I'm coming on board, but I still have one foot on the harbour wall for now too..

 

Come on Shed, admit it, you have one foot and two toes on the harbour (snow) wall... And you're pleasantly enjoying yourself...

[Dean E]

Not sure why people are going as far ahead as next weekend and saying 'Its not showing snow or its not cold enough ect.' Thats over a week away, if you remember yesterday, the models didn't even have Sunday covered. (The models are better today, but not 'nailed')

 

Anything +96 hours in my opinion should be taken as trends only. Its still a very finally balanced situtation.

[Severe Siberian icy blast]

I know it's the wrong thread but just to clarify a few things ,there is an ongoing fairly potent wave 1 activity hitting the stratosphere from now all the way through to day 9

Easing off somewhat toward the end.

Along with decent wave 2 picking up just in time when the wave 1 eases somewhat ,

There is stress on the vortex over the next 10 days , so yes that might not mean a split vortex all the way through the strat but it may well be enough to split it , as we have just seen recently about the effect our weather next week , so with everything considered things are looking a lot brighter than what they did 4 weeks ago .

[Dean E]

someone post the ECM snowcover charts please from weather bell --- that may support.

 

Snowman- its almost impossible to speculate-

 

maybe south of london

 

As far as I'm aware, the Weather bell ECM doesn't have snow cover charts...

 

Heres the GFS for Sunday though, interesting to say the least 

 

[mountain shadow]

The GEM evolution was the one that was on the cards a few days ago, but is the solution that has been binned by most of the models. It would indeed bring some proper winter to our shores.

 

However I cant see it happening. 100hpa chart this morning out to 10 days once again - vortex beginning to reform with its centre still down over Greenland:

 

 

and then the 30hpa chart for the same day in early Feb showing a vortex shape under stress but anchored over the atlantic and in a position to continue to support a pattern that will fire more lows over the uk

 

 

Decent levels of vorticity too still forecast over the atlantic at the same time:

 

 

 

There really isnt any way to soften the blow of this prognosis. To get height rises under these circumstances over Greenland is going to be very tough. Chio suggested that the scandy high might hang on and that our cold may come from the east when he was musing a few days ago, but if these strat charts are accurate (and bear in mind they tend to verify much better in broad patterns than the detailed trop charts do...) then we are looking towards the end of February for anything dramatic to build - and by day 10 wave 1 warming is fading.

 

The only crumb of comfort at the moment is that we appear to have a signal for a renewed wave 2 warming through the first week of February. Once again we can say that this might deliver... the vortex is certainly weakened and is no longer the beast that it was 3 weeks ago - but the ever growing possibility is that any impact of such an attack may not be felt until we hit March...

Hi Catacol, a good post, but my first thoughts when I read it were "ok, ECM forecasting increased vorticity in the Greenland corridor of death in ten days time, however, we already have a strong Scandi high in place, so where will the energy from the increased vorticity go?, Under the block or over it?"

I'm not sure we can answer that for certain yet.

[shedhead]

Come on Shed, admit it, you have one foot and two toes on the harbour (snow) wall... And you're pleasantly enjoying yourself...

Unfortunately been there, seen it, done it and still got the scars to prove it Glenn, so no way am I gonna morph from cold Grinch into Frosty par deux overnight...

 

Things certainly look more promising, especially when compared with what we have had to endure to date, but until we can be assured the LP will dive SE early next week and finally open the door to some proper cold air I will remain.....let's just say 'relatively hopeful..certainly no more at this stage.

Edited January 24, 2014 by shedhead

[Summer Sun]

The met office still expect westerly winds to return by the end of next week, before that we have a risk of easterly gales and showers turning increasingly wintry in the north and north east, longer term temperatures will be mostly rather cold, but near normal at times in the south.

[draztik]

It has been interesting watching the models ebb and flow over the last few days, with the ECM/UKMO supporting a colder outlook, while the GFS still *6z incl.*, not so keen in having much cold air in situ over the UK in the coming week, certainly compared to the Euros.-

 

Looking at the ECM det., the jet sinks into Europe next wk, lows from the Atlantic move in a ESE direction across the UK, so with heights to our NE, we should see a much colder feed of air into Britain from the East. ECM then sees a stall in a secondary low over us, which should deliver snow for the Midlands and further N.

So, I do think we will see some snow (for a time) but it looks to be of the wet variety, and personally I'm not a fan of that type, but I'll take it over rain! Thereafter, we see the models take us back to a westerly outlook…

 

Summary, 6-10 day outlook, heights ecm ens

Winds generally coming in from E/SE, in association with troughing to our S.

 

10-15 day heights, ecm ext

-westerly returning, negative anomaly in Europe not as pronounced, but with this setup, it does appear temps will stay below average.

 

GEFS also keen on a return to westerly flow mid term; Looking at the other LR models, we see an agreement in terms of the westerly being restored. The updated JMA ensemble for wk 3/4, and CFS ensemble wk 3/4 (fairly consistent trend from these models into this time period over previous updates). Edit : forgot to mention the EC32 also shows troughing a key feature to our NW into the longer term.

Edited January 24, 2014 by draztik

[snowking]

WeatherBell snow accumulation out to +240 from the 0z ECMWF Det.

 

 

Bear in mind not to take the actual depths shown too seriously as this is based upon a 10:1 snow to liquid equivalent ratio - something that is unlikely to be true under marginal conditions, nevertheless it shows that the 0z ECMWF det. was indeed a snowy run and suggesting otherwise is a little misleading.

 

Of course that is taking this at true face value, this does not mean this is what will necessarily occur.

 

SK

Edited January 24, 2014 by snowking

[Frosty.]

Darren Bett is a mild ramper point one.Secondly it is far too early to be making statements saying that a cold spell is on its way with snow and ice likely to the general public as panic will set in when the pattern is not set in stone.Still much more runs needed to be sure by no means a certain.

It's within the reliable timeframe now, well within it so i'm certain the landscape of the NH profile will look like classic winters of old by next week, and disruptive snow.

[Suburban Streamer]

someone post the ECM snowcover charts please from weather bell --- that may support.

 

Snowman- its almost impossible to speculate-

 

maybe south of london

 

 

This is from wunderground. only goes to 180hrs. ECM 0z:

 

 

(about as useful as the gfs snow charts)

 

EDIT: Just seen SK's post

Edited January 24, 2014 by Suburban Streamer

[EML Network]

What kind of statement is that to make then post the above images?

 

The GFS is fantastic for cold and snow towards the end of the month and into February.

 

 

Also regarding the ECM:

 

 

 

 

 

The whole country is under -5C 850's - and you come out with that statement.

 

I can't help but feel you are rather on a massive Wum, or simply don't know how to read the charts properly.

 

Even Shedhead's coming on board and that's saying something.

I won't ''come on board'' until I see snow falling from the sky !!

 

those charts above we both illuded to are for 2nd Feb.

 

How many times this winter are we looking at charts that ''might'' deliver something snowy more than 7 days out ?? only for it to never materialize.

 

It amazes me that some of you on here simply don't ever learn and fall into the same trap time and time again.

 

To get snowfall you don't just need uppers of or close to Minus 5.

 

You need dew points lower than 0, you need to look at the ''wet bulb'' and the higher the humidity the better.

 

You also need to look at the larger picture and I'm sorry but the charts for next week look too marginal, you only need to look at the ensembles to see that things are on the wrong side of maerginal for most of us.

 

 

I'll be only too happy to come back here on 1st Feb and say I was wrong when the country grinds to a halt because of heavy snowfall, I doubt however many of you would come back and hold up your hands and say YOU are wrong, when we're in the midst or more wind and rain.

 

the ECM is clearly showing a NW feed later in the run and the GFS is showing a return to Westerly drive weather in it's later stages, similar to yesterdays 06z run in fact.

 

I'd LOVE it to snow next week, god oinly knows I love snow as muxch as everybody else, but I'm not going to allow myself to be lead up the garden path by charts that are close, but not close enough IMBY and I've learn't the hard way not to get excited about a North Westerly epecially if the cold air isn't already in place before it arrives !!!

[Fozfoster]

Unfortunately been there, seen it, done it and still got the scars to prove it Glenn, so no way am I gonna morph from cold Grinch to Frosty overnight...

 

Things certainly look more promising, especially when compared with what we have had to endure to date, but until we can be assured the LP will dive SE early next week and finally open the door to some proper cold air I will remain.....let's just say 'relatively hopeful..certainly no more at this stage.

Shed, this rain we should of had today has gone into France which saying to me the block is stronger than the models thought, so that can only be a good thing going forward. Yeah.

Cheers Foz.

[shedhead]

One or two would be wise to take on board EML's latest post, nothing is guaranteed at this stage, all we can currently say with 100% certainty is the upcoming period repesents the best chance so far this winter of actually seeing some winter...or at least winter as the vast majority in here like to think of it.

 

The post from Frosty earlier was I'm sure tongue in cheek, but they can and often do raise the expectation bar to levels way above where they should really be, especially given everything currently available to us.

Edited January 24, 2014 by shedhead

[Neilsouth]

Need some advice, I always was led to believe that we need -10 850's and not -5 which people keep going on about. Especially in streamers as it's the difference between sleet and snow. So why are so many excited with the models? Where is the interest?

 

[legritter]

Great forum today ,but how are or why people quoting latest met office update when its not on met office site yet .perhaps its only me but still seeing yesterdays cheers .

[shedhead]

Shed, this rain we should of had today has gone into France which saying to me the block is stronger than the models thought, so that can only be a good thing going forward. Yeah.

Cheers Foz.

I see it as far more +ive than -ive Foz as my earlier post suggesed, but the whole set up going forward is still very much knife edge, if not razor edge. Too much emphasis given to one side could result in us having something 'cut off' that we'd rather hold onto...and I'm not talking about a Biscay LP. Next 48hrs of charts now look critical, the improving trend needs to continue and even gather pace if possible.

Edited January 24, 2014 by shedhead

[smhouston]

Need some advice, I always was led to believe that we need -10 850's and not -5 which people keep going on about. Especially in streamers as it's the difference between sleet and snow. So why are so many excited with the models? Where is the interest?

 

You've been told wrong then, there are many factors that dictate whether it is snow or not. You can get snow with less than -5 850s

 

Read John Holmes will it snow guide

[Neilsouth]

You've been told wrong then, there are many factors that dictate whether it is snow or not. You can get snow with less than -5 850s

 

Read John Holmes will it snow guide

 

Yes I know that as it's happened before, but when it comes to streamers much less likely.

[DTHFCJ]

Great forum today ,but how are or why people quoting latest met office update when its not on met office site yet .perhaps its only me but still seeing yesterdays cheers .

Refresh mate its updated now.........