Model output discussion - another cold spell on the horizon?

[Kasim Awan]

4 minutes ago, That ECM said:

Bit early for Willy waving competitions again. Not sure anyone should be doing that in these 850’s

 

seriously tho, stop the point scoring please.

The charts you have referred to there are actually conducive for a major snow event across Southern UK, even to the coast. 

[ItNeverSnowsInWindsor]

7 minutes ago, mountain shadow said:

We are locked and loaded now.

What can go wrong?!

The Iberian high for starters ?

[That ECM]

1 minute ago, Kasim Awan said:

The charts you have referred to there are actually conducive for a major snow event across Southern UK, even to the coast. 

Indeed And it will change but not my point

[Scott Ingham]

3 minutes ago, Kasim Awan said:

Almost nailed on now mate - all major NWP now swinging in that direction is a definite sign - plus the background factors etc, would be very unlucky if this were to retreat. 

It could retreat as quick as its come such is the nature of the ssw but yes it fits wavelengths expected and background factors. 

Love to see some continuity today

Its another good call if it comes off from the GFS in this synoptic.

[mountain shadow]

And we're not at FI anymore.

The cut off low in the North Western Atlantic is the trigger and is on all the model output now. 

The UKMO is not completely there yet though and we need tonight's 12z to firm up on it.

[carinthian]

11 hours ago, carinthian said:

Interestingly the latest Met Office fax shows a slowing down of the warm front progress for mid -week. The NE of Britain stays in cold air.  Would not be out of the question to see a wave development along the front with a risk of snow on the colder side. The UKMO model in my view seems show an upgrade , especially 96t-144t with a slower deconstruction of the high and transfer of energy further south and east. This progress then could release some real colder air from the north and east . A lot to be decided this coming few days.

C

 

Well done UKMO. This mornings run carries on from what it was indicating last evening ( re: above post ) with the trough dropping over the  British Isles into the continent. Longer term 144t-192t looks like the secondary wave shown over Southern Greenland ( chart below ) will be the feature that will release the real cold air from the Arctic towards the British Isles and sort of backed up by the other models generally this morning. However, thats still some days off. What really fascinates is in the shorter time span Tues -Fri this week with regards to the frontal movement shown on the fax charts. . Certainly signs of it holding. What will it produce in terms of potential snowfall ? I should get a up-date from the team over here later this morning ( snow computer ) % results with specific  interests for you many cold lovers back home.

[Drifter]

10 minutes ago, Kasim Awan said:

Almost nailed on now mate - all major NWP now swinging in that direction is a definite sign - plus the background factors etc, would be very unlucky if this were to retreat. 

Oh dear......it is never and I mean never nailed on. 
I’ve been burnt too many times by these bloody models. 

[Scott Ingham]

10 minutes ago, CreweCold said:

Maybe they should pick an ensemble member to be the op. Might be an outlier less often!

Its just so poor in the Greenland locale.

Now a scandi high and split energy of a slider.

Ecm is your girl!

[Liam J]

Well GFS will be having a laugh this morning looking at the 00z ECM good performance from GFS so far this winter. 

Flipped...  Let’s hope this is the start of solid continuity. Don’t flip back.  

 

Edited January 11, 2021 by DisruptiveGust

[O'Maille80]

10/10 output this morning. An exciting week of model watching awaits.

[Scott Ingham]

7 minutes ago, mountain shadow said:

And we're not at FI anymore.

The cut off low in the North Western Atlantic is the trigger and is on all the model output now. 

The UKMO is not completely there yet though and we need tonight's 12z to firm up on it.

Get the cut off low at 120 and we go cold. Then its a question of how cold and snowy

[DavidS]

Fascinating NHP in deep FI on the GFS

[KTtom]

16 minutes ago, That ECM said:

Bit early for Willy waving competitions again. Not sure anyone should be doing that in these 850’s

 

seriously tho, stop the point scoring please.

Good post, there is a PM function for self congratulating...Make it less norsious for us eating breakfast!

[BARRY]

2 minutes ago, Drifter said:

Oh dear......it is never and I mean never nailed on. 
I’ve been burnt too many times by these bloody models. 

WE HAVE TO STAND BACK AND OBSERVE 

 

[Kasim Awan]

Well, glad I stayed up tonight to watch the output. Had a strange feeling this would be quite a pivotal moment. It certainly is pivotal - however not entirely conclusive as the pattern is still 160-200h out & so caveats with regards to changes etc are very much present. 

The interesting take away, and a strong point for newbies I feel, is that "verification stats" and the whole idea of "verification" as a single figure is flawed. Now, spatial & temporally indexed verification is where it's at. Some models are better at dealing with certain areas, synoptic problems, and time ranges. For example, it is quite evident that the GFS is somewhat better at dealing with strong Greenland amplification episodes, with other models lagging behind... this certainly evident in the past month of model watching. One to bear in mind & hopefully those in the field (researchers) will post more of this perhaps a comparative study which would be of huge use to model analysts.. To help them make judgements about which model's solution is more realistic given the synoptic challenge & time scale. Especially if there is a seemingly inconclusive split in the output between models. 

Edited January 11, 2021 by Kasim Awan

[Kasim Awan]

8 minutes ago, KTtom said:

Good post, there is a PM function for self congratulating...Make it less norsious for us eating breakfast!

Yes in hindsight I probably went a bit too far with that... it's effectively the GFS & Scott whom I was praising, this came across as self-directed. Anyway, moving on, here's to a 12Z which sustains the trend. 

[Griff]

240s as far as I can see. 

Well this is going to be interesting. 

"he's not a Greenland high, he's a very naughty boy"... Or something similar. 

(remember one and all please be nice, it's Monday after all) 

 

 

Edited January 11, 2021 by Griff

[Stu_London]

Upper aren't as good on the ECM as it deepens the low and drives it further south than the other models.

Still a snowy run - probably rain to snow event in the far south.

[sheikhy]

Any news on the snow thursday friday?!or has it pushed all eastward again

[Vikos]

Just dropping it...

 

   Para

Edited January 11, 2021 by Vikos

[Griff]

Just now, Stu_London said:

Upper aren't as good on the ECM as it deepens the low and drives it further south than the other models.

Still a snowy run - probably rain to snow event in the far south.

Patterns and trends, rather than expending energy on FI precipitation charts etc? 

Saul Goodman 

[mulzy]

This is far from a done deal folks.  There is significant scatter on the GEFS and EPS through the medium range.  Lots of less cold options are still on the table - this morning’s mean EPS though decent is not as cold as previously.

[Stu_London]

Just now, sheikhy said:

Any news on the snow thursday friday?!or has it pushed all eastward again

to far east on GFS - not sure on other models

[Griff]

Just now, mulzy said:

This is far from a done deal folks.  There is significant scatter on the GEFS and EPS through the medium range.  Lots of less cold options are still on the table - this morning’s mean EPS though decent is not as cold as previously.

That goes back to the recent discussion of higher res op more likely to spot a development sooner than the eps? 

Plus mean is skewed by extremes? 

Plus my wishful think.  

[northwestsnow]

1 minute ago, mulzy said:

This is far from a done deal folks.  There is significant scatter on the GEFS and EPS through the medium range.  Lots of less cold options are still on the table - this morning’s mean EPS though decent is not as cold as previously.

LOL!!

Det jumps on board, eps moving the other way??

Clearly this saga might have legs in it...