Model Output Discussion - Spring Has Sprung

[johncam]

Absolutely heehaw cold on offer in current output , think as a lot have been saying for a while , thats it for this winter. Very dissapointing considering what the all the forecasts met included were saying . Another mild winter on the cards. Aw well always next year.

[joggs]

Absolutely nothing on offer for a half decent cold spell. Forget 10+ days ect. This winter has been dire and defied alot of decent signals.

Called winter over a couple of weeks ago due to the winter following the same pattern of not been conducive to hlb IMO. 

Been great to read informative posts from Tamara and Eagle especially.

Goodluck to the odd few chasing a fruitless chase rest of the season.

I feel in a warming climate,Iberian heights are here to rule.

Anyway,a bust for most predictions, models.

Alot of learning to do.

See you in November for another(no doubt) disappointment

[Bricriu]

The background drivers didn't fail, they are just a reminder  that they do not guarantee  cold for us. Something has overriden them and the signal for a back loaded winter. No doubt next winter we will have a strong pv over Greenland. Well at least in that scenario we won't have our hopes raised by any UKMO long range forecasts

[E17boy]

Hi peeps,

Hope all of you are well. I threw the towel in nearly 2 weeks ago and I was right to do so as nothing has changed the outlook to anything colder. Just thought I say my final thank you to all for this season, all your posts have been a pleasure to read. I will probably be back here  when we start getting our humid days and my attention turns to thunderstorms.
 

So what do we take away from this season, well I am sure there will be many questions and scratching of heads a season which we hoped would deliver but has ended disappointed The weather will always do what it wants and we will continue trying to predict it’s outcome which as this season has proved may not play with outside factors. Thank you all once again and those who do not join the summer storm boat I hope to see you all again next winter season. 
 

all the best

stay safe

and finally 

SADLY THE SEARCH FOR OUR WINTER WONDERLAND HAS COME TO AN END 

regards

[cheeky_monkey]

 Bricriu  E17boy discount a strong basin wide El Nino at your peril ..there is your head scratcher and winter overriding factor IMO 

[Hotspur62]

This February really has been a bust in terms of what the models predicted and I really thought in terms of the winter months it held the best chance of a wintry spell for the U.K. as a whole.It was only mid late January that all models including the GLOSEA model that showed a real blocked picture and for them all to be wrong has totally bemused me tbh.I know we are only 14 days into Feb but now the models are pretty much all in agreement for next 10 days that there will be no blocking so that pretty much covers all of February.I had always held GLOSEA in high regards but just goes to show you that all the best models can and do get it wrong(this also happened last summer as well).Something is causing this but what?Is it simply the warm SSTs?I don’t have the answers as I am not qualified enough but something is going on which worries me for the future as the World continues to warm at an alarming rate.

[Rain All Night]

Lol @ SSW...

...although it's interesting that the mean falls to zero in a few weeks' time

Edited February 14 by Rain All Night

[nick sussex]

 Rain All Night

It used to be that strat forecasts were much more reliable than the normal outputs . Sadly that hasn’t been the case , combined with the useless EC46 fantasy charts and the ensemble colder clusters at medium range imploding it’s been a very poor show from the NWP when predicting cold .

 

[Uncertainty]

Might be time to get the towel ready.

The models have been appalling this winter. Seasonals, ec46, ensembles, Ops: all guilty. I’ll see if this euro trough comes off, about 40% of eps members support the gfs op. If not… I’ll hoy it in.

@Hotspur62 factors I can think of:

- high solar, in times of high solar I feel the models over estimate blocks and downgrade them as it gets closer, the inverse is true for low solar. Just my opinion, not wanting to start a debate. 

- Hunga Tonga impacting the strat

- the mjo has flattered to deceive - although in general I do feel it has led the pattern. 

- The Nino has been too strong and not east based enough and the lingering effects of the +iod were unhelpful

- the pathetic SSWs we have had have spoilt favourable trop patterns by revving  up the Atlantic, twice. (Ridiculous  to think about but somehow totally unsurprising)

- the eternal model bias towards over amplification in the extended 

The last one is the main reason I am losing the joy in what we do. It’s almost as if the modellers need to add an extra 2x to the Atlantic. It’s under modelled 80% of the time.

[stodge]

Evening all

A lot of negativity on here tonight and it's not hard to see why.

However, we do have, based on GFS OP and Control, an "interesting" storm set to move over us at the end of next week which would doubtless be named whatever the next name is.

Other models not so keen on the storm coming as far to the south but the Atlantic train rolls on into the last week of the month with yet more rain and wind as the jet edges back south.

The vortex does continue to look weak with another strong warming later in the month so far too early to be negative about March and the seasons take little notice of the arbitrary definitions of when season should begin and end. 

There's also the not unjustifiable thought we might get our most favourable winter synoptics in spring - cold Easter anyone?

[damianslaw]

Theme of the models today trending towards less amplified flow late month, but still a signal for the atlantic trough to inch east, albeit it may struggle to clear the UK.. meaning we may exchange a very mild rather dank outlook for something more wet and wild with temps back closer to average, northern parts exposed to polar maritime air but nothing overly cold.

A single anomaly of February since 2013 has been the propensity for it to deliver exceptional anomalous warmth on a number of occasions with mild long drawn south westerlies, apart from 2018 and weak attempt early 2021 the absence of northern blocking and winds from between north and east has been notable.. those classic scandi feb highs seem from a bygone age. Don't worry they'll be back to make there annual appearance at some stage in spring no doubt! 

Edited February 14 by damianslaw

[LRD]

8 minutes ago, nick sussex said:

EC46 fantasy charts and the ensemble colder clusters

Agreed. The ECM clusters have been useless this winter (and last). But they're anomaly charts which are not to be trusted in the slightest. The EC46 has also performed poorly despite me defending it at times this season.

Speaking of which and not that it matters much bearing in mind its record this last 2 months or so but the EC46 has lost pretty much all meaningful northern blocking. However, it does go with some potentially cool mobility in the last days of this pathetic 'winter'. So northern hills could see a last hurrah in terms of something even slightly resembling winter weather

I hope it's right. Bring on a very pleasant spring and a warm summer with plenty of widespread thunderstorm activity

[Met4Cast]

1 hour ago, Bricriu said:

The background drivers didn't fail, they are just a reminder  that they do not guarantee  cold for us.

Unfortunately as highlighted by myself & others in recent days, “background drivers” have been against the idea of a significant high latitude blocking episode. 

It seems a major SSW is now unlikely too with a relatively quick sPV recovery compared to recent forecasts. 

Very odd winter in terms of the stratosphere. 

[stodge]

18 minutes ago, Met4Cast said:

It seems a major SSW is now unlikely too with a relatively quick sPV recovery compared to recent forecasts. 

Very odd winter in terms of the stratosphere. 

I don't think a "major" SSW was ever on the cards. What we are likely to see is another hint of a split but this time a less dramatic recovery - the zonal wind speeds forecast (15 m/s) are still on the low side of average - and this seems confirmed by the briefest of breaks in the Atlantic dominance in the last week of the month.

March continues to show a prolonged further weakening back towards zero so you'd expect the Atlantic train to slow again with more opportunities for heights to build and amplification to occur. We could end up with a warm early spring or we might not. 

As we see, the response to a strong Wave 1 is to re-strengthen the vortex so the signs are March will see a gradual weakening which might be more conducive to blocking on our side of the globe.

Edited February 14 by stodge

[Met4Cast]

1 minute ago, stodge said:

I don't think a "major" SSW was ever on the cards.

Just 2 runs ago 100% of EPS members had a technical reversal (Major SSW) The GFS was less keen but still had a significant number of members reversing u-winds. 

So in fairness expectations of a major SSW were high. 

[feb1991blizzard]

 Met4Cast

Whether or not a technical SSW is now irrelevant, they aren't going significant negative for any length of time and its a (unfavourable) displacement not a split.

[WYorksWeather]

Sorry everyone, but I'm not getting into a chase into March. The BFTE was an exceptional event and in any case it began around the 24th February - any repeat now would likely be too late to produce anything for most of us especially given the overall levels of warmth in our vicinity compared to previous years.

In any case, there is a post-mortem thread so I'm not going to get into that discussion here.

Medium range

The GFS ensemble is continuing to downgrade any late-month cold, so I think it's increasingly looking like a win for the ECM ensemble here, which has consistently been uninterested in a late month cold spell. The GFS still has a little way to go with the climbdown, but the ECM basically has no cold spell whatsoever.

And in a new low, if you look at the ECM you can't even cherry pick the ensembles for anything very cold or snowy. There's not a single run that gets the 850s down to -10C at any point for the rest of the winter.

A record mild February is absolutely on the table, and if we don't get there it's likely to be fairly close. Bonkers, especially given the previous long-range modelling.

SSW

The SSW forecasting from ECM also shows decreasing support for an SSW, and as I highlighted as a possibility, is now increasingly showing a quick vortex recovery. This is also known as a reflective SSW, which we saw in January, and is actually more likely to promote mild conditions.

SSTs

As usual, SSTs for days 0, 5, 10 and 15. The clock is definitely ticking, and here's why. The day 15 chart is still colder than day 0, but for the first time, it is now similar to the day 10 chart. The move to rising SSTs is on the way.

Here are the same charts, but in anomaly terms. The one constant, as I've been highlighting for weeks and weeks (I must sound like a broken record!) is that huge warm pool near the Azores, which is turbo-charging the mildness of our south-westerlies. We should continue to expect exceptionally mild conditions whenever that wind direction occurs.

Meteogram

Taking all this into account, it's no surprise that the ECM meteogram for Reading has absolutely nothing of note on it whatsoever if it's cold you're looking for. At most, the mean is showing a descent from exceptionally mild tomorrow, through very mild over the next week or so, to slightly milder than average or near normal to round out February.

Summary

After a brief period where I called attention to the GFS ensemble but noted its disagreement with ECM, the GFS is increasingly converging to the ECM solution of at most a few days of nearer average conditions, but nothing especially cold to round out February. The SSW increasingly looks poor for cold prospects as well. To top it all off, the SST charts show that we really don't have much time left, especially in the context of the general levels of warmth this year.

As a result, we're most likely done for winter at this stage I think. I'm therefore going to suspend my hunt for cold and swap to looking for the first warm days of the year, which for me would mean a widespread 18-20C. I may still swap back to winter mode if something notable comes out of the blue.

[Rain All Night]

11 hours ago, Rain All Night said:

0z deterministic runs, Wed 14th to Wed 21st (day 7)

Very little new to say as we watch the big purple blob approach... heights put up a little bit more of a fight on ECM than on GFS.

0z ensemble means, Wed 14th to Thu 29th (day 15)

The big purple blob arrives on our shores on 21st (GFS) / 22nd (ECM) Feb. GFS has it produce a deeper low height anomaly into Europe than ECM.

The Atlantic ridge / Scandi trough signal that we had been seeing originally then duly arrives from around 26th Feb (day 12), but it doesn't stick around for long.

Strictly just for fun, the ECM control run offers an illustration of what could lie behind the ensemble mean...

12z deterministic runs, Thu 15th to Wed 21st (day 7)

Whilst there is divergence on the finer details from Tuesday onwards - ECM lets the high pressure put up more of a fight before presumably being blown away - ultimately the same outcome looks inevitable in about a week's time, based on the ensemble means below.

12z ensemble means, Thu 15th to Thu 29th (day 15)

We seem agreed on the arrival of the big purple blob on either 21st or 22nd Feb, but ECM is now losing interest in subsequent troughing to our east; GFS still makes more of an effort in that regard, around 26th Feb, but beyond that, it converges with the ECM in suggesting quite a significant-looking build of pressure approaching us from our west - could we be heading for a more settled start to spring?

Just for fun, here's a cherry-picked ECM ensemble member that illustrates the outcome I'm imagining, based on those ensemble means...

Edited February 14 by Rain All Night

[WYorksWeather]

Just had a look, and again don't rate this for accuracy, but EC46 has fully flipped and is now mild, mild, mild through to the end of March.

19/02 - 26/02:

26/02 - 04/03:

04/03 - 11/03:

11/03 - 18/03:

18/03 - 25/03:

You just have to laugh!

  

[Daniel*]

Deary me…

 

[Cloud 10]

What a bizarre run from the 18z,deep trough comes crashing in from the NW and then decides to have a love-in with the UK which results in a rather nasty storm.

 

Not to be taken literally at this range of course,but one to keep an eye on.

 

[Froze were the Days]

 Hotspur62 Read the post above yours - not many posters I read last month mentioned a strengthening El -Nino (largely a cold party pooper) all I read was AAM that, MJO phase this, SSW that etc. etc. also Iberian Heights have been relentless the last few weeks, if you think it's been bad here just look at the near continent. Not sure about the SST's either as they've been close to normal with a slight tri-pole in the North Atlantic which can be inducive to a more southerly tracking jet stream but other than that it's always a struggle.

I'm always set up to be disappointed before December arrives most Winters now but 2023/24 has been on another level, the worrying thing is I feel there will be worse winters which will give us small hope of any cold spells (as per mid-January) just around the corner...

Edited February 14 by Froze were the Days

[ICE COLD]

 Cloud 10 lol according to the 18z it’s a snow storm down here . Well that won’t happen

[Daniel*]

Unbelievable wrt AO… I’ve never seen such a huge model bust for polar blocking in mid/late Feb, something that had total cross model agreement only a matter of days ago. 

 

A week ago!

Edited February 14 by Daniel*

[offerman]

 Hotspur62

I feel that it’s higher pressures, more stagnated topography of these, forcing up milder winds from the south and south-west, so the pressure charts often resemble in reality very similar patterns to our Southwest, and these are particularly strong in recent years and a hard to shift out of the way

So I’m not sure when these long-range forecasts come out they are looking at certain drivers for sure whether they include these recent stagnant high-pressure systems. Well that I’m not so sure of. 
 

if you turn a standing fan on, and it’s blowing cold air with no obstruction in the way, but if you put a wall in the place of the flow, this will disrupt this colder flow of air, and if you have a strong wall with a strong, counteracting driver behind it. This will inevitably. Prohibit the colder, incursions and certainly any longevity, but make it very difficult to get any cold in place

The wall is equivalent of the high-pressure systems that we have encountered through most of this winter to our Southwest

 

Also, just to add to my last post, the fact that there has not been any particularly strong Arctic high-pressure systems as well, but also they seem to have been many more smaller disturbances, and as we all know, it only takes one small disturbance in the far north to disrupt any potential flows south, plus there’s also been warmer sea temperatures as well, so the warmth has been exacerbated still further from our Southwest.