Model output discussion - Winter has arrived

[Skullzrulerz]

13 minutes ago, jules216 said:

Arctic High anomally is impressive only if we could drain the High Pressure away from Europe

This could become a concern if this was to happen 

Hopefully closer to the time we will be able to see less high pressure around Europe though of course there's a lot to go though yet 

 

[ITSY]

Obvious cherry picking and not even close to the mean (which is far, far less amplified) but P18 has the right idea! 

 

[STRiZZY]

1 minute ago, ITSY said:

Obvious cherry picking and not even close to the mean (which is far, far less amplified) but P18 has the right idea! 

 

18z, P18.. Something about that number huh? 

[DEYS(Kent)]

Am I the only one in here looking at the current NH profiles from various sources and thinking, “hmmmm?” Plenty of interest for me. On a day the MetO say that snow could be a thing of the past...

[jules216]

3 minutes ago, Skullzrulerz said:

This could become a concern if this was to happen 

Hopefully closer to the time we will be able to see less high pressure around Europe though of course there's a lot to go though yet 

 

 Euro high very well linked to a cut of low close to UK/IE, that though could aid the WAA to link with Arctic high, so you can't win, good overall hemispheric view at the cost of poor Europe for time being days 7-11 probably at least. Only if WAA happened about 1000km to the west,but you never win these days in Europe, its like we are cursed

[Eagle Eye]

1 week Hot, the next freezing Cold

A dep low approaches just before the Cold.

The H500 showing an interesting angle

An explosion of pink, in the northern hemishpere, a cold Snap.

A sign of things to  come.

Another Western Ridge setting up looking Good.

[Eagle Eye]

A certain Slavic word beggining with B comes to mind Holy (insert Slavic Word) 2 days before Christmas.

We've got another Beast from the East.

Edited December 7, 2020 by XanderP007

[johnholmes]

I have to say that, in my view, they are about as reliable as the oft mentioned chocolate teapot1

Looking at the 500 mb charts over the next 2 weeks, see below, and they do not suggest any outbreak of genuine cold in that time. Yes, there is the broad band of +ve heights and ridging across the chart from northern Europe/Russia west but the upstream pattern is not, yet, conducive to any buckling the 500 mb flow. Well not in my view anyway. That is during the next 2 weeks.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.ncep.noaa.gov//favicon.ico Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

[Eagle Eye]

3 minutes ago, johnholmes said:

I have to say that, in my view, they are about as reliable as the oft mentioned chocolate teapot1

Looking at the 500 mb charts over the next 2 weeks, see below, and they do not suggest any outbreak of genuine cold in that time. Yes, there is the broad band of +ve heights and ridging across the chart from northern Europe/Russia west but the upstream pattern is not, yet, conducive to any buckling the 500 mb flow. Well not in my view anyway. That is during the next 2 weeks.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.ncep.noaa.gov//favicon.ico Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

I can Dream

[jules216]

Considering 6Z GEFS seems to have usually a progresive Nature its good to see they bring the cold anomalies closer to Európe within the reach of Christmas period

[Decemberof2010]

P18 is basically the dream

The majority of the others are reality. 
 

I like dreaming

 

[terrier]

So lovely looking gfs06z run. But now here is the but. Wasn’t we told yesterday when it was showing the Atlantic moving in it was discounted as been the more over progressive run of the day. And to discount it.! Now it’s showing winter nivarna deep in FI it’s great. I’d love to see those charts verify for Xmas week but we all know deep down that it won’t happen. Just find it funny how the gfs is like a love hate model. When it shows what we don’t want it’s garbage. But when it’s showing these cold runs it’s amazing. Anyway let’s see what this evening model output shows. But I’d certainly wouldn’t be betting my mortgage on a cold and snowy Xmas. 

[TSNWK]

Just now, terrier said:

So lovely looking gfs06z run. But now here is the but. Wasn’t we told yesterday when it was showing the Atlantic moving in it was discounted as been the more over progressive run of the day. And to discount it.! Now it’s showing winter nivarna deep in FI it’s great. I’d love to see those charts verify for Xmas week but we all know deep down that it won’t happen. Just find it funny how the gfs is like a love hate model. When it shows what we don’t want it’s garbage. But when it’s showing these cold runs it’s amazing. Anyway let’s see what this evening model output shows. But I’d certainly wouldn’t be betting my mortgage on a cold and snowy Xmas. 

Absolutely! Love it when it behaves in the bin when they misbehave.  I mean truly whatever happened to Harmony from last week..

Dumped without a second thought.. ruthless bunch we are.. 

[Kirkcaldy Weather]

5 minutes ago, terrier said:

So lovely looking gfs06z run. But now here is the but. Wasn’t we told yesterday when it was showing the Atlantic moving in it was discounted as been the more over progressive run of the day. And to discount it.! Now it’s showing winter nivarna deep in FI it’s great. I’d love to see those charts verify for Xmas week but we all know deep down that it won’t happen. 

I wouldn’t be so sure of that still a long way to go but my interest continues to grow for the run up to Christmas, it isn’t just a sudden appearance of these colder charts they have been popping up for a decent amount of time (certainly over the last few weeks at least). It’s definitely an interesting time for model watching and maybe becoming more interesting as we head toward ’s time

[PiscesStar]

1 hour ago, ITSY said:

Obvious cherry picking and not even close to the mean (which is far, far less amplified) but P18 has the right idea! 

 

YES please!!

Edited December 7, 2020 by DiagonalRedLine
Reply was stuck inside the quote box

[alexisj9]

36 minutes ago, TSNWK said:

Absolutely! Love it when it behaves in the bin when they misbehave.  I mean truly whatever happened to Harmony from last week..

Dumped without a second thought.. ruthless bunch we are.. 

Well it was right, and stuck to it, ECM was right once then moved away. I think it will appear again next chance of snow, or storms, it's pretty good in the short term re where ppn will be. It's not a model for looking forward.

[Geordiesnow]

I see the GFS love in is back given its colder output to in the much longer range. Reality is, it was right in trying to bring the Atlantic in and it will get milder again. Could be significantly mild also with double figures widely expected.  

As usual, the Arctic high will be very hard to model, the orientation in the longer term is perfect for cold to flood down the Eastern flank but its not a set up we see often these days sadly. Hopefully the trends of the Russian high weakening continues, biggest waste of time and will never deliver significant cold. 

All in all, apart from longer range potential, there is nothing really too cheer about for cold lovers sadly. 

[frosty ground]

8 minutes ago, Geordiesnow said:

I see the GFS love in is back given its colder output to in the much longer range. Reality is, it was right in trying to bring the Atlantic in and it will get milder again. Could be significantly mild also with double figures widely expected.  

As usual, the Arctic high will be very hard to model, the orientation in the longer term is perfect for cold to flood down the Eastern flank but its not a set up we see often these days sadly. Hopefully the trends of the Russian high weakening continues, biggest waste of time and will never deliver significant cold. 

All in all, apart from longer range potential, there is nothing really too cheer about for cold lovers sadly. 

Okay and do you have anything to add related to the models? 

What about the 2m temperatures, yes the show it getting milder, but significantly so? I am not sure.

The GFS getting the Atlantic in eventually is not the win you think it is, even more so when its not actually happened yet.

I agree there is nothing in all the output in the near term that would bring cheer to the cold hunters heart, beyond day 7 thou there is plenty of  potential for the longer term, I am surprised you have not read about it from the many contributors to this forum or even seen any evidence of this your self, hang on you mention an artic high so you can clearly see it but I suppose if something is rare it never happens and therefore never happened which is very illogical.

 

 

 

[northwestsnow]

Clearly we are looking at an unsettled phase, perhaps aided by the Russian High as Atlantic lows disrupt...

However, there are signs we are seeing some effects are beginning to be seen up in the strat. Zonal winds are forecast to relent and we still have easterlies at the bottom of the strat preventing a coupling...

There are reasons to be hopeful im sure, I get the jitters when we see a Euro high building, let's hope it can push North ...

[jamesgold]

Could be a stupid question, if this decoupling between the trop and strat persists, does this negate any (or most) effect from decreased zonal winds due to stratosphere warming up?

Sorry if this is the wrong thread for this sort of question

Edited December 7, 2020 by jamesgold

[swebby]

5 minutes ago, jamesgold said:

Could be a stupid question, if this decoupling between the trop and strat persists, does this negate any (or most) effect from decreased zonal winds due to stratosphere warming up?

Sorry if this is the wrong thread for this sort of question

I'm not sure it matters?  In that, if coupled, the strat vortex can only help drive the trop vortex, it's absence due to sudden warming means no driver.  Basically the engine is turned off so it does not matter if the clutch is engaged or not?

[chionomaniac]

2 hours ago, johnholmes said:

I have to say that, in my view, they are about as reliable as the oft mentioned chocolate teapot1

Looking at the 500 mb charts over the next 2 weeks, see below, and they do not suggest any outbreak of genuine cold in that time. Yes, there is the broad band of +ve heights and ridging across the chart from northern Europe/Russia west but the upstream pattern is not, yet, conducive to any buckling the 500 mb flow. Well not in my view anyway. That is during the next 2 weeks.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.ncep.noaa.gov//favicon.ico Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

I agree that it unlikely to see any genuine cold in the next two weeks ( snow producing and sticking cold), John, but as you know I tend to look for what the models are not showing too!

What I think we are seeing is a classic precursor pattern with background underlying states that could all come together to produce something just out of range. I often find these far more interesting, than when we have severe cold forecast in a day or two, as it involves sticking your head above the parapet and being prepared to be shot at. Not all precursor trop patterns will eventually deliver genuine cold -in fact not many, but being able to look at the bigger picture and recognising the potential that is not shown by any models yet is where the skill is.

This being the model thread it is not right to criticise those who orthodoxily comment on the models and what they show - we need that more than ever so that we all remain grounded. But likewise, when conditions are ripe and potential exists then it is the discussion of this that makes this thread so appealing to many.

[chionomaniac]

So, those who have been asking about the strat and disconnect need to understand that there are two forecast events occurring in the next ten days. One is wave 1 displacement that is propagating down from the top of the strat towards mid levels and the other is a secondary wave 2 split event propagating upwards ‘internally’ from the lower strat upwards.

 

The above upper wave 1 event can be described as a barotropic quasi stationary wave - ie the wave is in the same place as we drop lower into the strat with set areas of higher and lower pressure. This so far is dynamically fairly stable and may take time to evolve before we can see how the strat will be affected by it. The wave 1 displacement loses intensity as we head to the middle strat.

the next image above is at the tropopause - where trop and strat meet and shows a weak wave 2 event that is being directed from the trop directly. This type of chart and situation is of far more interest to us current, because the strength and size of the split can influence the severity and longevity of any associated mid lat trop cold outbreaks. However, because it relies heavily on trop conditions and forecast modelling of these, this type of split can be forecast one minute and be gone the next, so the further out timewise the far less reliable. 

The disconnect that we see is that rather than the upper and middle strat controlling the lower strat and then trop, both upper strat downward propagating conditions and lower strat upward propagation are ‘meeting in the middle’ . When the upper strat becomes dominant throughout the whole strat then we will see a return to more normal +AO trop conditions. Unless of course, an upper warming starts to affect the upper strat and weaken it significantly, and just perhaps we may be seeing that too.

[Chesil View]

42 minutes ago, northwestsnow said:

Clearly we are looking at an unsettled phase, perhaps aided by the Russian High as Atlantic lows disrupt...

However, there are signs we are seeing some effects are beginning to be seen up in the strat. Zonal winds are forecast to relent and we still have easterlies at the bottom of the strat preventing a coupling...

There are reasons to be hopeful im sure, I get the jitters when we see a Euro high building, let's hope it can push North ...

Euro heights building with a displaced and uncoupled strat vortex, worth looking in the wetterzentrale noaa archives for Jan 16th -18th 1947 to see what that can be a precursor for.........

[throwoff]

5 minutes ago, Broadmayne blizzard said:

Euro heights building with a displaced and uncoupled strat vortex, worth looking in the wetterzentrale noaa archives for Jan 16th -18th 1947 to see what that can be a precursor for.........

Lot of talk of 47' this year. I am not super familiar with it but I keep seeing it pop up all over the place.