Model Output Discussion - Spring Has Sprung

[Dennis]

a short view to the Vortex 10Hpa' (50Hpa)

a new Canadian warming is forseen and a displacement too 

time to get ready for winter next month 

 

[Gowon]

Not bad from the ICON as it manages to split the blob over Greenland:

[Rain All Night]

2 hours ago, Catacol said:

I cannot help but curse our luck this month. First a failed SSW, and noone expected it to fail - indeed the strat big guns all came out and started to celebrate in the run up - and then a really positive tropospheric setup that has been undermined and stalled by an unexpected and not fully understood impact of strat developments. It could all have been so very very different!

It's whether the probability of something unexpected like these two things occurring can be estimated that interests me, as if we can't do that, then I don't see how we can put a confidence level on a forecast. It was a surprise to me when the (earlier) SSW didn't occur and then again when the flattening occurred so quickly and stuck, just because the forecasts to the contrary had sounded so confident.

Edited January 24, 2024 by RainAllNight

[Dennis]

also MJO 7 shows up

[Gowon]

The GFS has moved towards the UKMO:

 

Voila!

[Gowon]

The GEM is also joining in:

[Dennis]

Ideas are that the Vortex is heading to E  (or split) on the world map

then its waiting for the Greenland HP 

 

See latest NAM

Edited January 24, 2024 by Dennis

[Cold Winter Night]

UKMO 168h makes more of those lingering heights over Scandinavia as a new Atlantic wave approaches.
It may slowly get more difficult for the Atlantic to push through.

GEM also ends with a more amplified Atlantic and lower heights into Europe at 240h.

[bluearmy]

Ukmo is consistent with its idea of stalling the Atlantic and show’s disruption 

Be nice to see ec pick that baton up later 

 

[AO-]

GFS isn't that bad when looking at the different members at day 8. About half are fully zonal and the rest show a disrupted tpv. Among those three are some potent members, I suppose. Keep in mind that this is "only" at T192.

[Rob 79812010]

Well Well Well! The models starting to show promise. And Net Weather deliver a bombshell no one expected. Second half of Feb we could be talking 'substantially colder' says the monthly forecast

[damianslaw]

I guess the main theme emerging in today's models for early February timeframes, which is firmly outside the reliable still, is for a more amplified atlantic flow to take hold, largely as a result of the polar vortex stretching and splitting, with a lobe moving into scandi. Mid atlantic/UK heights most likely result.. memories of Feb 05 are coming back after a very wet stormy January.. 

 

Edited January 24, 2024 by damianslaw

[JBMWeatherForever]

Things starting to look interesting across nearly all the models for a return to significant cold early in February.  The signal being picked up today looks significant and I think some very wintery synoptics will be appearing imminently.  

[Methuselah]

This week's Met. Office Tend-Day Trend. . . more model uncertainty: 

 

[northwestsnow]

EC is dirge

Still flat at day 9

[Kasim Awan]

Stonking Bartlett on this run.

[ANYWEATHER]

52 minutes ago, JBMWeatherForever said:

Things starting to look interesting across nearly all the models for a return to significant cold early in February.  The signal being picked up today looks significant and I think some very wintery synoptics will be appearing imminently.  

If you back that quote with actual charts that would be good please! Because at the moment ,I only see high pressure to the south and low to the north ,generating mild west or south westerlies

[northwestsnow]

Absolutely no sign of winter on EC det .

Let's hope it was a horrid outlier ..

So sad this thread is so dead in the heart of winter

Edited January 24, 2024 by northwestsnow

[Metwatch]

A question for the few most knowledgeable on this here:

If we didn't have various mountain ranges on the planet like the Himalayas, Andes Rockies etc, and were just areas of flat landmasses or even part of the oceans, what implications on the AAM and GSDM would that have? Perhaps the +AAM wouldn't be able to rise up as much as it can do with these mountain ranges present which give mountain torque, and so high latitude northern blocking becomes even rarer without any forcing from the stratopshere? I suppose we would still have frictional torque playing a key role assuming the earth doesn't stop rotating.

Edited January 24, 2024 by Metwatch

[mountain shadow]

  @Metwatch just look to the Roaring Forties in the Southern Hemisphere for the answer to that.

Round and round they go with no deflections due to land masses.

Edited January 24, 2024 by mountain shadow

[Dennis]

lets start on this idea , EC cant hold back on other parameters

 

Edited January 24, 2024 by Dennis

[Quantock]

38 minutes ago, northwestsnow said:

Absolutely no sign of winter on EC det .

Let's hope it was a horrid outlier ..

So sad this thread is so dead in the heart of winter

Indeed, the EC not budging on its elimination of winter.

This winter I’ve taken to following the UKMO first and foremost and I reckon it’s been pretty solid in pointing the direction albeit only at the T144-168 timeframe it offers.  GFS has done its thing of showing trends in FI, sometimes a yes and sometimes a no but then that’s not surprising.  ECM seems to have done a lot of following - picking up trends only when they have been shown by the others.  Of course this could be my imagination but I thought I’d mention It..

So I’m hopeful that the EC diet is ‘behind the curve’ in pointing the way to a colder Feb.....

[WYorksWeather]

Still awaiting the ECM 12z ensembles for comparison purposes, but I'm not seeing a huge amount of interest from the GFS 12z.

This just looks mostly near average or above average at 850hPa, and then slightly above average by day and mild by night initially, dropping back to average by day but still mild by night as we move into February, with occasional brief shots of something closer to average.

There is admittedly more variation into early February, and there are some colder runs, but it's still slightly above average overall (which is admittedly better than raging mild).

Even if I take the furthest GFS 12z mean at T+384, there's nothing really going on here. All there is a slight relaxation of the heights over Iberia. There's no sign of a block over Greenland, or a Scandinavian high. There's not even a mid-Atlantic ridge or a UK high.

And if we look at the 850s, the deep cold at -8C is well away to our north, roughly in line with Iceland or central / northern Sweden.

So, with a lack of any blocking, and the deep cold several hundred miles north or east, I'm not seeing a quick route to cold from here. The 0C line is over the UK, but that is just indicating average conditions for the time of year rather than anything cold.

I've already consigned January to the bin. If we get to the weekend still seeing this sort of thing, it'll be time to do the same for the first week of February. 

Our remaining hope is probably tied into the fact that the seasonal models picked up a strong blocking signal for February, the Met Office are continuing to talk about potential cold for the middle of February onwards, and potentially some positive teleconnection signals. We need to hope that something is on the horizon, and the models just aren't picking it up.

I await the ECM ensembles for comparison...

 

 

[Dennis]

the westerlies will be knocked out by a sudden dive AO/NAO 

[MJB]

  12th -19th

 19th -26th

 26th 4th