Model output discussion - The run up to Christmas

[swfc]

Ec is OK at 192 hrs. Not as much ridging   but Atlantic door shut.Good day coming I feel

Edited December 23, 2020 by swfc

[Cheshire Freeze]

EC at day 8 has the same bulge of low heights into Canada as the GFS control...let's hope that isn't a signal to be latched on to.

On the control it sparks the jet into sinking the Atlantic ridge with the jet steaming over the top.

Edited December 23, 2020 by CreweCold

[mountain shadow]

Two consecutive posts saying two different things.

No wonder folk get confused.

[Cheshire Freeze]

1 minute ago, mountain shadow said:

Two consecutive posts saying two different things.

No wonder folk get confused.

Just a passing observation from me. May get away with it on EC but it's a banana skin in the evolution.

[dragan]

4 minutes ago, mountain shadow said:

Two consecutive posts saying two different things.

No wonder folk get confused.

They both have good and similar points however 

Edited December 23, 2020 by Blessed Weather
Unnecessary comment removed

[That ECM]

2 minutes ago, mountain shadow said:

Two consecutive posts saying two different things.

No wonder folk get confused.

Two different outcomes. Crewe was highlighting a concern. T192-T216 be awhile before we know. 

[swfc]

Ec locks the door fi seems a bit closer on that run but it's split the PV and altho west based can't complain at that heading threw January 

[Cheshire Freeze]

2 minutes ago, CreweCold said:

Just a passing observation from me. May get away with it on EC but it's a banana skin in the evolution.

We do get away with it this run. However, I'd like to see UKMO and ECM pull more towards the GFS op run around day 5/6 later on.

[swfc]

1 minute ago, CreweCold said:

We do get away with it this run. However, I'd like to see UKMO and ECM pull more towards the GFS op run around day 5/6 later on.

Yes crewe it's a bit less smooth than gfs or aligned as to say. Hopefully all good later today on all output.

[northwestsnow]

9 minutes ago, CreweCold said:

Just a passing observation from me. May get away with it on EC but it's a banana skin in the evolution.

EC is excellent...

[That ECM]

5 minutes ago, northwestsnow said:

EC is excellent...

Yep.

[Valleyboy]

5 minutes ago, northwestsnow said:

EC is excellent...

Yep, looks like EC will drop a few snow bombs in various locations.

[swfc]

15 minutes ago, mountain shadow said:

Two consecutive posts saying two different things.

No wonder folk get confused.

Tbh that's the point. Options and opinions, makes the world go around. The varience on models does manifest this strange thing during conversation

[carinthian]

23 hours ago, carinthian said:

Morning all. I have an update from the team over here in relation to the above post sent yesterday morning. Based on the current consistency shown by the models this morning , the outer perimeter results shown by the snow model computer increases the risk of snow now to 40 %  during the period 29th /30th Dececember. They forecast  spreading out of the 1000-500mb thickness ( dam ) value of 528 or slightly below over England and Wales especially. These values would be in the range for snow to occur. The exact location cannot yet be determined  ( maybe with-in 48hours period if current synoptic persist ).  By New Year they expect the trough to align its axis from Greenland to Northern Germany , which is good news for extending the colder and possibly snowy conditions with-in the British Isles .

C

Morning all. I have an update for you following on from the above post yesterday. Really no change as we head to a colder end of year. Consistency in the models shown out to 144t and the team over here still expect  the same trough alignment to keep the British Isles in a cold unstable air mass. The latest parameter results this morning now show 50% snow risk for the United Kingdom generally towards the end of this month. Any predictive values above that moves into the realms of probable snowfall rather than possible. The parameter results provided recognize  a number of important features and interactions and can distinguish  the complexity of different air mass on land and sea ( always a complication regarding the UK ) regarding the forecast of snow. The fine mesh model used will only provide reasonably  accurate results with-in 48 hours of a predictive event. However, the good news does show forecast thickness 500-1000hpa values of below 528 over much of the British Isles by 30th December. Always a good indicator in the hunt for snow. Meanwhile in the Austrian Alps , another day of unseasonal warmth beckons but looks like snow for Christmas !

C

Edited December 23, 2020 by carinthian

[bluearmy]

16 minutes ago, northwestsnow said:

EC is excellent...

 

10 minutes ago, That ECM said:

Yep.

It’s drifting though in its latter stages on each run ..... if a strong feature develops unexpectedly upstream (or even over Europe)  then it will skew the current meandering output later on. Uppers remain abnormally high to our east ...... a good illustration that if it’s cold somewhere then it is v likely to be the opposite somewhere not too far away!

we usually expect the euro trough to fail somewhat come verification...... 

[That ECM]

1 minute ago, bluearmy said:

 

It’s drifting though in its latter stages on each run ..... if a strong feature develops unexpectedly upstream (or even over Europe)  then it will skew the current meandering output later on. Uppers remain abnormally high to our east ...... a good illustration that if it’s cold somewhere then it is v likely to be the opposite somewhere not too far away!

we usually expect the euro trough to fail somewhat come verification...... 

if strong feature develops unexpectedly upstream then we will have to evaluate the output accordingly. As coldies I get some will look for problems and concerns. As we are talking about day 6,7,8,9,10 there is always that possibility.

worrying about something unexpectedly happening and therefore not being able to know what it looks like seems pointless.  We just watch with interest. NW had said ECM day 10 was excellent. It is imo.

 

[TSNWK]

8 minutes ago, bluearmy said:

 

It’s drifting though in its latter stages on each run ..... if a strong feature develops unexpectedly upstream (or even over Europe)  then it will skew the current meandering output later on. Uppers remain abnormally high to our east ...... a good illustration that if it’s cold somewhere then it is v likely to be the opposite somewhere not too far away!

we usually expect the euro trough to fail somewhat come verification...... 

Morning BA I and I'm sure are most appreciate your thoughts and knowledge sharing for balance.

Any thoughts on this mornings GFS please? 

[bluearmy]

a large part of the ‘holy grail’ of wintry hemispheric set ups showing on the gefs late on now with the southern arm linked up all the way around ..........

the gfs ops are certainly playing with this seventies/eighties winter type set up which is very much high risk/reward for the U.K. as a west based NAO could change the cold for warm within a day or two as heights rise across W Europe and drag a sou’wester across us ......the flip side of that is we stay just the right side and potentially receive copious amounts of snowfall!  
 

[Chesil View]

36 minutes ago, That ECM said:

if strong feature develops unexpectedly upstream then we will have to evaluate the output accordingly. As coldies I get some will look for problems and concerns. As we are talking about day 6,7,8,9,10 there is always that possibility.

worrying about something unexpectedly happening and therefore not being able to know what it looks like seems pointless.  We just watch with interest. NW had said ECM day 10 was excellent. It is imo.

 

Not sure we need to concentrate that much on up stream as that door seems pretty much shut. What caught my eye on the ECM is the gradual hieght rises between Iceland and Northern Norway in the final few frames.which is essentially where the GFS goes after 240

Edited December 23, 2020 by Broadmayne blizzard

[bluearmy]

8 minutes ago, That ECM said:

if strong feature develops unexpectedly upstream then we will have to evaluate the output accordingly. As coldies I get some will look for problems and concerns. As we are talking about day 6,7,8,9,10 there is always that possibility.

worrying about something unexpectedly happening and therefore not being able to know what it looks like seems pointless.  We just watch with interest. NW had said ECM day 10 was excellent. It is imo.

 

completely get your post - given the dropping zonal flow high up we could well see a period where these meandering charts do actually verify. It’s unusual but the background set up is supportive I guess

5 minutes ago, TSNWK said:

Morning BA I and I'm sure are most appreciate your thoughts and knowledge sharing for balance.

Any thoughts on this mornings GFS please? 

it’s plausible ...... the envelope is a cold one but it’s one of those big ones !  With developments high up, coldies are looking forward to an Xmas period of model watching to match some of the best over the past fifteen years!  

[mulzy]

7 minutes ago, bluearmy said:

a large part of the ‘holy grail’ of wintry hemispheric set ups showing on the gefs late on now with the southern arm linked up all the way around ..........

the gfs ops are certainly playing with this seventies/eighties winter type set up which is very much high risk/reward for the U.K. as a west based NAO could change the cold for warm within a day or two as heights rise across W Europe and drag a sou’wester across us ......the flip side of that is we stay just the right side and potentially receive copious amounts of snowfall!  
 

Yes, that west based negative NAO is a risk, albeit a small one for now.  The ext EPS mean for day 15 is ridiculous - never seen that level of height anomaly over western Greenland that far out..  For safety I wish everything was a little further east but a very decent ext EPS suite.

[sheikhy]

Guys its done man!!we heading for what could be a notable cold and snowy period!!all 3 models look amazing!!!

[Sky Full]

A look at the UK surface temperatures over the next 10 days as (currently) predicted by the GFS:

There’s an increasing a amount of frost being shown both by day and by night, and this can only be amplified in the days following if the current NH charts verify......

[jules216]

10 hours ago, Catacol said:

It’s been a poor winter so far for Central Europe....but in response to more complaints about the Russian High - without it I don’t think we would be looking at such a meridional pattern now and the end of Atlantic influence, and in addition it is still incredibly early! It is only Dec 22....and if the split SSW happens (another product part driven by that Russian High) then probably cold will come to Europe. The U.K. will need some luck to ensure cold (some good stats on this over on the strat thread) but mainland Europe less so.

The meridional pattern has so far had you on the warm side. This won’t last....

In my 10 plus years of weather watching I have never seen such a great blocked hemisphere produce nothing in the way of wintriness in continental Europe, same story this morning cut of low UK-IE and SCeuro-Western Russian ridge,never really making any inroads to line up for an easterly flow in Europe or a better placed low pressure, it always seem to find the worst position. Tropical low frequency forcing seems to be circulating around same locations in MC and forcing rinse and repeat patterns in Europe. Even on twitter so much hype like never before in recent days, yet T2M revenue is as bad as in most zonal winters. Maybe I should put on my glass half full approach rather then looking at reality outside my window. What makes you believe that pressure patterns will line up better if there is no indication of it on 15 plus day modeling. Yesterday 12Z EPS produced coldest T850hPa of staggering -2C in location 670m high and at 360hr mean there is still the same signal of low pressure around UK-IE and Western Russian high that never makes in to a proper easterly flow in Europe. Waiting for potential 2 week cold weather in February after wasting 6 weeks  of winter just wont do it for me, of course I am very much aware that this pattern is perhaps the most beneficial for you guys in UK-IE more then any other European location, so enjoy the slice of luck you are going to get in the way of wintriness as upstream of that low pressure we will be getting ridiculous advection of southerly winds yet again

[ICE COLD]

Morning, I love keep waking up to 100+ new posts in here even tho the last time I was on here was 11:30 last night . The output is amazing this morning. 

 

Edit - I didn’t post the UKMO I’ve heard it not that great , so I’ll leave that out for now

Edited December 23, 2020 by ICE COLD