Model Output Discussion - Snow for some, but what else is in store?

[BARRY]

1 minute ago, mb018538 said:

Sounds about right to me. Outlook is looking pretty poor on the whole barring some transient snow events. Certainly not very exciting in my view anyway.

nomality returns to these shores.

[Radiating Dendrite]

5 minutes ago, Vikos said:

Aha, so it seems, they can handle it?

14th 00z vs 16th 00z for 24-1-21

 

Now 25th in comparission today 00z / yesterdays 00z

 

Or lets do it with a 10 days prognosis of 850is for today

6th Jan +10 days

 

I hope you get my point...

Think you need to repost your images my friend. Either that, or it is so complicated the models have given up. 

[TEITS]

14 minutes ago, WINTRY WALES said:

Good to see you TEITS

Quick question with regards to those trends. Would they be trends you noticed in winters over the years with a Non SSW driven trop? Would the effects of this SSW have an effect on those trends?

Just an observation of trends in winter when blocking is involved be that in Greenland/Scandi or both.

I know some disagree but I still believe these models have a historical bias programmed into them and always try and return to default weather pattern. This is when models come unstuck when blocking over higher than normal lattitudes occurs. For example the Arctic high has always been a nightmare to forecast for these models.

I do not expect a sudden flip but a slow move towards what I describe.

[Vikos]

1 hour ago, Tim Bland said:

we have reverse zonality just to our north and this is likely an effect of the SSW.

Can you name the layer? Ok, 10hpa, thats upper Strat.

In 150hpa I can't find the reversal (yet). Note: 150hpa is lowest Strat, more like Tropopause, 11.000meters hight

 

Nor in 100hpa

 

This is the strongest reversal I found in 30hpa, impressing -0.8m/s

but will turn positive in 10d forcast

 

What I want to say, that a reversal "downstairs" hasn't yet happend ( or I am just to blind to see it in the charts)

[ptow]

2 hours ago, Penrith Snow said:

I do like the ECM at 240 not for the actual surface conditions although it would be interesting in Scotland but for the reverse wind flow easterly to our north which could so easily shift south.

Look at this chart for late December 1978, looks so much like the ECM (although ECM 240 looks more favourable) yet 3 days after that December 78 chart southern Britain was swept by a severe blizzard.

Just saying.....

Andy
 

 

Those 2 charts are far from similar. 

[Jeremy Shockey]

ECM 0z ensemble mean

Looking towards 23rd / 24th for our next snow opportunity and the mean uppers have improved quite a a bit.

 ECM 0Z Op @ 168 hrs

The Op for Sat 23rd looks good. Just need a shift South so that we are all in the game.

[Vikos]

14 minutes ago, Radiating Dendrite said:

Think you need to repost your images my friend. Either that, or it is so complicated the models have given up. 

Thanks. Updated it, so press STRG+F5 for full reload of the site, then they should show.

Sorry....

[sunnijim]

7 minutes ago, Vikos said:

Can you name the layer? Ok, 10hpa, thats upper Strat.

In 150hpa I can't find the reversal (yet). Note: 150hpa is lowest Strat, more like Tropopause, 11.000meters hight

 

Nor in 100hpa

 

This is the strongest reversal I found in 30hpa, impressing -0.8m/s

but will turn positive in 10d forcast

 

What I want to say, that a reversal "downstairs" hasn't yet happend ( or I am just to blind to see it in the charts)

Sorry if this has been mentioned elsewhere,and it may or may not be relevant?

The M.O 10 day trend forecast mentioned the recent warming and how it can lead to the reversal.

The interesting bit I took was that on this occasion it has only 'partly reversed' so I'm guessing the effects have taken place but we are not seeing the complete reversal hoped for? Hence why we have this rather uninspiring set of runs in recent days...

 

[Ice Day]

The 850's debate has been this winters big conversation on here.  Snowking's excellent post from a few weeks ago put a lot of misconceptions to bed and just to add in that according to the GFS 0z run, the uppers over me now are 0.1c.... and it's snowing!

Anyway, using Chiono's recommendation and looking only out to 144, the morning runs were pretty good.  Just slight tweaks in the right direction and the UKMO and ECM would be very good.

  

[winterof79]

As we leave Jan and move toward February. 

What is going to happen to the remainder of the PV

Surely that bodes well. One more warming and its possibly curtains. 

[sebastiaan1973]

34 minutes ago, Vikos said:

Aha, so it seems, they can handle it?

14th 00z vs 16th 00z for 24-1-21

 

Now 25th in comparission today 00z / yesterdays 00z

 

Or lets do it with a 10 days prognosis of 850is for today

6th Jan +10 days

 

hope you get my point...

I don't see any important differences, that matter to us. It remains more or less the same. No cold weather.
Edit grammar.

Edited January 16, 2021 by sebastiaan1973

[Captain Shortwave]

The models have returned to the suggestion of heights drifting westwards into northern Canada once the jet stream breaks through underneath the Atlantic ridge.

 

 

 

At this time deep cold looks unlikely. However we do appear to be in a rather cold and cyclonic set up. Anything to steer areas of low pressure further south from the Atlantic would be most welcome. Perhaps a left over wedge of heights to the north/north west would probably be sufficient to feed Atlantic lows into the trough near the U.K. at the right trajectory to deliver snowfall.

The polar vortex at the lowest levels looks knackered, it is just a shame that at the moment the hemispheric pattern isn’t falling that well for us. However the risk of significant snow is still on the table, even if the likes of widespread ice days and negative double figure 850s are not.

[Badgers01]

1 minute ago, sebastiaan1973 said:

You prove I'm right. No, important differences, that matter to us. For our part of the world it doens't it remains the same. No cold weather.

I totally agree those images show the general themes and trends were correctly predicted surely ! 

[sebastiaan1973]

Here you can see average of EC240h yesterday and this morning. Not much of difference.

[offerman]

14 hours ago, nick sussex said:

Thanks . Unfortunately everything that can go wrong does in tonight’s outputs .

It’s very disappointing for coldies but we’ve been here before , many times .

 

Hi Nick

completely agree with you again. 

Years ago I used to make the mistake of looking too far out and seeing cold charts sometimes repeating run after run but only to be disappointed in the near timeframe of 4 to 5 days literally getting water down day by day until left with a disappointing mild scenario.

so I learnt over the years to just ignore F1 charts as a complete waste of time snd emotions in winter. 
however they do seem to provide more support/direction sometimes in summer with regards to high pressures , but even here they are not infallible. I find they are more accurate in summer than winter but of course if and in summer things can go wrong too . 

 

so with regards to winter I just ignore F1 charts ,day 10 charts I just focus more so on 5 to 6 days but as we all know recently they can also be completely futile due to the current virtually Unforecastable Synoptics and slack systems all over the place at present. 

[IDO]

8 minutes ago, Vikos said:

Can you name the layer? Ok, 10hpa, thats upper Strat.

In 150hpa I can't find the reversal (yet). Note: 150hpa is lowest Strat, more like Tropopause, 11.000meters hight

 

If you look at the d10 ecm chart you can see what Tim means:

There are HP/wedges across from Siberia through the Arctic to the US, giving a mean easterly flow through those waypoints. That is rare and we can reasonable assume that it is the result of the SSWE? Who knows if we need a full reversal in the strat to cause that feedback in the trop? With the sPV on the move around and post that date it is suggested that this will be a short-term anomaly (3-5 days). This appears to be a one-off SSWE so we should maybe not expect a "normal" strat>trop redux?

[offerman]

13 hours ago, MATTWOLVES said:

Not much point adding the 4 or 5 days point though,its already been stated on here a thousand times by various posters..its more about keeping your emotions in check when viewing the output. 

Regarding John,he is basically saying what many are saying...the models are really struggling to nail anything down..but a mobile situation looks very unlikely. The point of this story being the models are providing more questions than answers right now. He doesn't rule out deep cold in February also. I think some may have been expecting a QTR following this SSW event..1stly...its only been around 10 days since the displacement,so in that respect we could be looking for the models to start showing the goods next week...on the other hand if its a much slower downwelling,we could be looking at 3-4 weeks.

The SSW that occurred in January 2013 was bringing us bouts of winter right through March,so we can't rule this out also. Also worth noting was the event was not a total split...more off a displacement,but worth baring in mind was the fact the Vortex was already weak and meandering,this warming just weakened it further. It may not recover for quite sometime,thats if it does at all.. So we will remain in the game throughout these coming several weeks. Im not so sure about the nina affect moving forward....for me I've always been sceptical of how this influences the UK,especially as we are so far downstream of the event..El nino  for instance as been linked to backloaded Winters in the UK..there are numerous examples...but also a fair few studies that show they have little impact on our Weather. Im not sure if La Nina is gonna bring us a strong jet come next month,or we are going to have a battle between the affects of the Strat and Nina battling for supremacy...interesting times from now through till Mid March is my opinion  

Edit...and on the other hand we may already be seeing some kind of reversal...to the North of us and spanning a hell of a long distance,as blue just pointed out.

Great post there Matt thanks ever so some much for that. 
I agree with you about the La Niña effect and would say eL Nino has a larger affect I have always thought that too. And yes I think you’re right as well about the 4/5 days comments . 

[Vikos]

7 minutes ago, sebastiaan1973 said:

I don't see any important differences, that matter to us.

Why you drop the 10day 850is GIF?

 

For our part of the world it doens't it remains the same. No cold weather.

Isn't this the synoptics thread, not the regional weather thread? Sorry, I am in the wrong thread, then...

[Vikos]

7 minutes ago, IDO said:

If you look at the d10 ecm chart you can see what Tim means:

There are HP/wedges across from Siberia through the Arctic to the US, giving a mean easterly flow through those waypoints. That is rare and we can reasonable assume that it is the result of the SSWE? Who knows if we need a full reversal in the strat to cause that feedback in the trop? With the sPV on the move around and post that date it is suggested that this will be a short-term anomaly (3-5 days). This appears to be a one-off SSWE so we should maybe not expect a "normal" strat>trop redux?

All plausible, but after seeing the EZ Scenarios yesterday, I doubt, that EC is performaning very good ATM, so I have little trust.

[Harsh Climate]

Quite suprised by the number of negative posts on here this morning, the outlook still looks wintry, cold at times, with the chance of snow in places up to 144h. And that's with all 3 big models in agreement GFS/UKMO and ECM!

Obviously there is a somewhat north south split, The next week looks good for the northern half of britain and poor for the southern half. With a more NW focus in the coming days that would obviously bring more westerly places into play. I think northern ireland and northwest england should be in on the game next week, perhaps some good accumulations and even modest levels of alltitude. As ever the higher your alttitude the greater chance of settling snow in this set-up. I think at times in the north westerly flow next weak with deep blues on the 500 uppers, I reckon low levels around belfast, manchester for instance should get in on the act.

We,ve just had a snow event I wont ever forget, 6" of snow (at 300ft) that has lasted untouched 36 hours from just a borderline battleground situation with no real cold uppers and a messy looking chart. Just shows we don't need these perfect easterly's and -12 uppers to get the good stuff.

I see the charts flipping from one extreme to the other over the last week or so, when will people learn, rather than placing all eggs in one basket run to run just take a step back and judge them all on a daily or even two daily basis, much less stressful and you can give a more balanced summary.

Someone tell me how the big 3 models are bad at say 144h, way beyond fi at the moment? Not the typical juggernaut of lows barreling west to east across the atlantic or the dreaded bartlett.

[sebastiaan1973]

4 minutes ago, Vikos said:

Isn't this the synoptics thread, not the regional weather thread? Sorry, I am in the wrong thread, then...

For our part of the world means NW-Europe

[northwestsnow]

5 minutes ago, sebastiaan1973 said:

For our part of the world means NW-Europe

But you said no cold weather.

And that is patently not true seb.

There is cold weather forecast in NW Europe .

Possibly snowy to across parts of the UK.

[sebastiaan1973]

1 minute ago, northwestsnow said:

But you said no cold weather.

And that is patently not true seb.

There is cold weather forecast in NW Europe .

Possibly snowy to across parts of the UK.

Okay, no significant cold weather for most of us. Of course there is always, on hills more chance on snow.

Edited January 16, 2021 by sebastiaan1973

[Garthvader]

12 minutes ago, Harsh Climate said:

Quite suprised by the number of negative posts on here this morning, the outlook still looks wintry, cold at times, with the chance of snow in places up to 144h. And that's with all 3 big models in agreement GFS/UKMO and ECM!

Obviously there is a somewhat north south split, The next week looks good for the northern half of britain and poor for the southern half. With a more NW focus in the coming days that would obviously bring more westerly places into play. I think northern ireland and northwest england should be in on the game next week, perhaps some good accumulations and even modest levels of alltitude. As ever the higher your alttitude the greater chance of settling snow in this set-up. I think at times in the north westerly flow next weak with deep blues on the 500 uppers, I reckon low levels around belfast, manchester for instance should get in on the act.

We,ve just had a snow event I wont ever forget, 6" of snow (at 300ft) that has lasted untouched 36 hours from just a borderline battleground situation with no real cold uppers and a messy looking chart. Just shows we don't need these perfect easterly's and -12 uppers to get the good stuff.

I see the charts flipping from one extreme to the other over the last week or so, when will people learn, rather than placing all eggs in one basket run to run just take a step back and judge them all on a daily or even two daily basis, much less stressful and you can give a more balanced summary.

Someone tell me how the big 3 models are bad at say 144h, way beyond fi at the moment? Not the typical juggernaut of lows barreling west to east across the atlantic or the dreaded bartlett.

Thanks great advice for a complete novice ,i find that in here is sometimes quite more volatile than the models

Edited January 16, 2021 by Garthvader
Grammar

[Griff]

9 minutes ago, Harsh Climate said:

Quite suprised by the number of negative posts on here this morning, the outlook still looks wintry, cold at times, with the chance of snow in places up to 144h. And that's with all 3 big models in agreement GFS/UKMO and ECM!

Obviously there is a somewhat north south split, The next week looks good for the northern half of britain and poor for the southern half. With a more NW focus in the coming days that would obviously bring more westerly places into play. I think northern ireland and northwest england should be in on the game next week, perhaps some good accumulations and even modest levels of alltitude. As ever the higher your alttitude the greater chance of settling snow in this set-up. I think at times in the north westerly flow next weak with deep blues on the 500 uppers, I reckon low levels around belfast, manchester for instance should get in on the act.

We,ve just had a snow event I wont ever forget, 6" of snow (at 300ft) that has lasted untouched 36 hours from just a borderline battleground situation with no real cold uppers and a messy looking chart. Just shows we don't need these perfect easterly's and -12 uppers to get the good stuff.

I see the charts flipping from one extreme to the other over the last week or so, when will people learn, rather than placing all eggs in one basket run to run just take a step back and judge them all on a daily or even two daily basis, much less stressful and you can give a more balanced summary.

Someone tell me how the big 3 models are bad at say 144h, way beyond fi at the moment? Not the typical juggernaut of lows barreling west to east across the atlantic or the dreaded bartlett.

Isn't the gem supposed to be up there these days? 

Suggest colder air from North East for Scandinavia later...