Model Output Discussion - Spring Has Sprung

[IDO]

Consistency with the GFS at D11-12 with the Iberian ridge firing up:

0z and 06z^^^

Pretty awful background signals forcing this.

[Downburst]

 Daniel* There is the North Atlantic and the South Atlantic. https://climatereanalyzer.org/clim/sst_daily/ I am happy with the usefulness of that long held geographical distinction.

[MJB]

We say about the lack of cold but get the HP in the right place and you just never know eh? I appreciate I am running out of straws but I have a few left to pick  

[minus10]

Looking at the gesf anoms 0z you could be forgiven for thinking that this is a good chart with blocking to the north west later this month..

...however all is not what it seems...it seems...i think as others have stated the blocking signal is there but it is not in the right place for the uk..too far north to be effective for cold. The trough underneath allowing milder air up from the south...

..the gefs mean also shows this...

More like an artic high ..while the op shows a meaty vortex again for around this time..only the op i know but talk about insult to injury!!

..in addition gfs op has been been at the higher end of the pack for a number of runs now with the mean also getting higher...

...this looks like a trend unfortunately...

Even the eps are milder...

..the EPS anoms (only going out to t270 at present on Titbits) also showing that north west hight rise but again looks like it will not be effective for delivering cold to the uk if it goes the same way as gefs..

..so although from a macro hemispheric perspective it may be going the way as dictated by the main drivers it seems as ever in the uk if the pieces dont fall right it wont make any difference...still can change of course and I really hope it does as would love to see a bit of proper cold before spring...but somehow i just feel it is slipping away...

...noticeable again this year the Daffs are up and out in some places...ground temps warmer than they should be...of course March colder snaps still likely and will cause problems for the flora...

 

 

Edited February 7 by minus10

[Chesil View]

 minus10

An excellent post and a point well made and one in line with what i feel i have learnt about them over my years on here

in my opinion The back ground drivers which I do believe control the general set up can at best only provide broadbrush picture of where ridges and troughs may set up. 

Its easy to get excited when we hear that a certain mjo phase favours Grenland high or Scandi high but worth remembering you can have a high in either of these locations that doesn't advect cold air across our tiny area of the globe. 

In fact the vast majority of scand blocking often just holds a trough in position over the UK with wet and mildish weather as a result.

Similarly with Greeland Highs the vast majority are slightly too far west and simply advect arctic air into the mid Atlantic.

There is no doubt in my mind that the background signal make the general broadbrush set up.  

But getting deep cold to advect across the UK is down to the very exact positioning and orientation of these Greenie and Scandi Highs and that is the detail the no mjo phase or gwo orbit or qbo or eamt event can yet successfully forecast for such a small island as ours.

So whilst I am always interested to hear from the brilliant experts about the drivers that we are so fortunate to have on this site.

I am also aware, as are they. That those drivers simply cannot tell me if its going to snow in my back yard or even my country.

All they can do is give an idea of where the balance of probabilities may lie in regard to getting  the cold to our shores and that is all they can and no more than that.

Edited February 7 by Chesil View

[Downburst]

Really given the extraordinary global sea surface global temps surely one has to question how this impacts everything. It is truly amazing the last few years and in particular right now these last 14 months. Plenty of El Nino Years since 1981 too, so I discount that. What the hell is going on, I am aware of 3 or 4 possibilities for north Atlantic quadrant, but no one seems to be sure. I mean if someone 20 years ago said, hey lets increase the world oceans surface temp 5% above climate average, I think we'd say, ah no, lets not do that, one doesn't know what might happen.

[Rain All Night]

13 hours ago, Rain All Night said:

12z deterministic runs, Wed 7th to Tue 13th (day 7)

I'm not sure what I'd been expecting to see next from the deterministic model runs, but it wasn't this. First we had the GFS start unexpectedly sending our low north and the other models then following suit, and now we have the GFS begin following this up with mild southwesterlies only for some of the other models to start showing that too. If deterministic runs out to day 7 were the only output you could see, and you'd not seen any longer-range ensemble or seasonal output or heard any professional or amateur teleconnections-based forecasts, then I don't think you would look at these charts and think that significant high- or even mid-latitude blocking is what's coming next. And yet it still could be, which is why we keep watching!

12z ensemble means, Wed 7th to Wed 21st (day 15)

After initially looking like they may be going nowhere, these ensemble means do, between them, just about manage to deliver the signals for Scandinavian and then Greenland blocking that we've become accustomed to seeing over the past few days, with ECM the most convincing. The Atlantic trough seems to be looking more and more menacing with each new set of runs, though it is nonetheless impressive for us still to get to day 15 without it taking over on these mean charts.

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

Most of these runs are showing long-fetch southwesterly winds either reaching, or very close to the UK by the end of week 1, and given the trend over the last couple of days, I wouldn't be too surprised to see that verify, although you can see on the UKMO and GEM that there is a possibly of either weak high pressure or weak low pressure sitting in the way of that southwesterly flow.

0z ensemble means, Wed 7th to Thu 22nd (day 15)

The models still think that we are likely to see rising heights over the UK and to our east that will prevent the Atlantic trough from advancing into us in week 2, but nonetheless that trough continues to look more influential with each new set of runs. Significant height rises to our northeast and later our northwest seem to be less well represented amongst the members of all three ensembles this morning than in recent runs, and you can see that from 21st Feb (admittedly very late in the run), a return to Atlantic low pressure systems seems to be well represented, though I wouldn't yet say "expected".

[Froze were the Days]

 Don Personally as said I haven't found it at all accurate after maybe the first week and a bit...will be about as accurate as some seasonal models for this Feb including GLOSEA...all about to fail miserably.

[Purga]

To be fair there is a lot of uncertainty (spread) within the latest GEFS dragging the mean down.

The mean chart for D10, as an illustration, shows a chance of a Scandi High is still vaguely on the table.

[Scandinavian High.]

All models seem to be all over the place at moment still think an easterly could pop up soon with an increase snow risk for eastern areas in next couple of weeks .

Edited February 7 by Scandinavian High.

[Rain All Night]

 Purga It's certainly there amongst the members, it's almost favoured even, but then have a look at the 850hPa temps it would bring in, there's not a lot of purple on show:

[MJB]

I know I keep banging this drum but with this still on offer from GFS why is there the expectation that the METO will drop something colder from the East.

 

[Battleground Snow]

The mjo going "backwards" really hasn't helped the chance of high lat blocking in mid February,

We really need it in 8, gfs and cfs just about do it later on in the month, (ecm hasn't updated today) but I wouldn't hold my breath about it making it,

Relying on a ssw to deliver is just pot luck, on how the deck falls after the event happens.

To add insult to injury, the snow for tomorrow has shifted 50 miles north on the overnight runs. I live in-between the a45 and M6 boxes on the map.

Even as one of the most optimistic coldies, this winter is wearing me down.

[MJB]

        

 

       

Just some charts that don't look especially great but there is cold around, maybe the expectation has gone through the roof this season. I still think we will get a cold spell of sorts with some snow around 

[E17boy]

 MJB These patterns may be on offer but as it’s been the case through this season these charts are always 9 or 10 days out and they have rarely come to fruitation. Going on todays charts if we are going to honest we have seen a downgrade to what was some days ago. I think the way things are going the expectation is that eventually Met Office will adjust their update accordingly. Keeping in mind that we don’t get another sudden upgrade in the next day or so.

regards 

[MJB]

 E17boy It's also been touted mid Feb. ish, but the weather isn't running to a UK timetable  , it can be delayed, the 46 has pushed for blocking mid Feb onwards, that is being shown on ECM and GFS and in the Met text forecast.

Let's just see where we go...........................no one has bad luck forever  

[AO-]

Good afternoon,

After recovering from watching the woeful output this morning, I would like to add a positive note. Taking the EC at 168h of this morning, there is not a lot of "effort" needed to get a Scandiblock. A bit of proper WAA and the block should be there. The models are stalling a bit in getting the cold where we want it. It doesn't mean it won't get there, but every day the chance of a serious cold spell is decreasing. At day 10 a Block is present. But in the wrong place. A bit more West would be nice. 

Edited February 7 by AO-

[Daniel*]

2 hours ago, Downburst said:

There is the North Atlantic and the South

On global scale yes but most of “North Atlantic” is not especially relevant to NW Europe at higher latitudes. Vast majority of that anomaly is coming from lower latitudes. Waters to our north, east and west are not unusually warm therefore the idea all wind flows are excessively mild is false. It’s southwest flows which are very mild and even milder. 

[Daniel*]

Well major SSW looking increasingly inevitable some GEFS runs dropping it to -20m/s which is impressive and benchmark of a very powerful event. It could be possible we see most significant SSW since February 2018 event but for the moment a split is not clear, it’s hard to see the vortex truly recovering into spring. I think the spring could be eventful this year just a feeling. 

[blizzard81]

Much better ecm o6z at T144. Scandi high much better positioned and orientated to advect proper cold our way. 

[Harsh Climate]

 blizzard81

Hopefull that the 12z runs can salvage something from a pretty dire change of output over the last 24 hours or so. 

Not one to throw the towel in early especially with a fair few background drivers in our favour but we need to start seeing something soon! Show us the 🌨.

Edited February 7 by Harsh Climate

[Scandinavian High.]

Meto not backing down something from the east could get interesting soon let’s see what models show later.

[Harsh Climate]

 Scandinavian High.

Just read it, hardly an inspiring update. We needs cold/snow from E / NE not 'colder conditions COULD develop in the east' and 'high pressure extending from mainland Europe' ( in other words a cold bartlett ) . Too late in the day for a slow burner I'm afraid.

[E17boy]

 Scandinavian High. yes METO have not backed away from colder conditions, which I thought they will after this mornings horror show. Looks like high pressures over the east will have influence next week eventually pegging temperatures down. Atlantic weather trying to encroach at times but with this high to our east does not look like any inroad progress. More emphasis is on drier weather. Longer term outlook still emphasising colder conditions could develop. 
 

 

[frosty ground]

 blizzard81

but there is nothing to advocate the air west so it makes no difference