Model Output Discussion - Into the new year

[Penrith Snow]

Anyone know where I can view historical 850mb temperature charts for the UK?

A link would be great 

Thanks

Andy

[iowpompeylee]

44 minutes ago, Mike Poole said:

South of the M4 event tomorrow according to HARMONIE 12z at T33:

But at least some of us are seeing snow on this run.

I have a lot of love for this model, seems to be more in situ with the met office than anything else. A lot of us southerners will have a ball of this comes off! 

[Frosty.]

Oh man, I love downgrades, especially when they look like this from the Gfs 12z op..this is not your usual dross garbage winter we have had recently!!!!!!!!!!!!!!!?

Edited December 29, 2020 by Jon Snow

[Griff]

3 minutes ago, Mike Poole said:

Very similar to current GFS at day 5 (it’s labelled GFSV16):

However, given the increased vertical resolution it ought to be better in the strat, and that will be a major player going forward so one might expect it to preform well over the next week or two.  

Seems likely that one is going to out perform the other... Toss a coin? 

[Johnp]

5 minutes ago, Penrith Snow said:

Anyone know where I can view historical 850mb temperature charts for the UK?

A link would be great 

Thanks

Andy

Use the drop down to change parameters.

http://www.meteociel.fr/modeles/archives/archives.php?day=31&month=10&year=2020&hour=0&type=ncep&map=4&type=ncep&region=&mode=0

Edited December 29, 2020 by Johnp

[Tim Bland]

Lots of negativity over this GFS(p) run. Just to add some perspective...some coldies would have given their left testicle (or breast) for this last year! Look at that cold to the north poised to collapse south! 

[SMU]

updated UKMET 36/42 & 60 showing the same as GEM

GEFs panel 36 looks good.

Edited December 29, 2020 by Steve Murr

[londonblizzard]

beast from the west?

[Penrith Snow]

2 minutes ago, Johnp said:

Use the drop down to change parameters.

http://www.meteociel.fr/modeles/archives/archives.php?day=31&month=10&year=2020&hour=0&type=ncep&map=4&type=ncep&region=&mode=0

Cheers John!

[kold weather]

13 minutes ago, Snowy L said:

Strange time to kill the high pressure given what is going on in the next layer of the atmosphere. Would think GFS will drop that idea after the SSW happens.

Its unfortunately shifting the blocking pattern way westwards, there is actually increasing pressur ein the arctic as the -ve AO really starts to take hold.

Its IMO a somewhat realistic pattern and has been increasingly advertised on the ensembles as well. I'd be surprised if we don't get another shot after that point given just how strongly blocked the arctic is about to go....

[Jeremy Shockey]

GEFS 12 z Ensemble mean @ t144

Not a bad mean for 4th Jan. There will be some lovely cold scenarios in there

[Scott Ingham]

6 minutes ago, chionomaniac said:

Yes of course. The reason we search for an SSW is so that we get a dramatic drop in the pv strength which reflects down to the trop. BUT, we are already seeing these dramatic reduction in trop u winds without this. So stop looking for that and concentrate on what is occurring in the trop now, and as you say worry about the SSW later. For all the papers we read, sometimes we have to just look around and use our common sense.

Yeah makes logical sense.

My brain always works like this because my passion is for the longer term.

Im roadmapping, unravelling the extended path in my head on a daily and its these uncertainties that make me dig deeper.

Simply though you are right. We all want a weak vortex and lower u winds to aid in blocking and ultimately cold weather and snow and your right that is already with us now anyway. I find the tpv winds quite remarkable atm for the time of year without a fully propagated ssw. Such an interesting winter this year!

[pureasthedriven]

48 minutes ago, Skullzrulerz said:

So you're thinking that the UKMO is a bust if it went on for longer ? 

May well trend the same way with the GFS/ECM?

Give me some short term love please! When does 2 months hence ever come off?! 

[Mike Poole]

GEM T144 and T204:

Looks like it is going for it.

 

[feb1991blizzard]

11 minutes ago, chionomaniac said:

Yes of course. The reason we search for an SSW is so that we get a dramatic drop in the pv strength which reflects down to the trop. BUT, we are already seeing these dramatic reduction in trop u winds without this. So stop looking for that and concentrate on what is occurring in the trop now, and as you say worry about the SSW later. For all the papers we read, sometimes we have to just look around and use our common sense.

Still think we need a wide and far wave 2 split through Greenland or Iceland replicated all the way down the atmosphere, i think its differing viewpoints based on peoples threasholds for a buzz and being excited, i really cant get excited about snow which is gone by 2 hours like todays, i am looking for those insane setups with -15c uppers and gale force winds slamming through the country.

[kold weather]

6 minutes ago, Steve Murr said:

updated UKMET 36/42 & 60 showing the same as GEM

If we can get some decent development on the low coming down the west side of the UK a wrap around event certainly becomes a possiblity, especially in the far east of the SE/EA. 

I'm personally not too interesting from an IMBY, its going to take a heck of a wrap around to get to the point it gets this far west, however I'll be routing for it.

I'll look at the GFS/GEM emsembles and see how well supported it is.

[Frosty.]

4 minutes ago, Jeremy Shockey said:

GEFS 12 z Ensemble mean @ t144

Not a bad mean for 4th Jan. There will be some lovely cold scenarios in there

Too me, it looks MEAN..moody and magnificent..but then, I’m a coldie..completely unbiased!

[Johnp]

There seems to be numerous disturbances / cold pools crossing the  country over the next ten days, so I'd expect several 'surprise' snowfalls to turn up at short notice. 

The GFS precip charts often falsely look dry at this range. 

Edited December 29, 2020 by Johnp

[kold weather]

Just a little heads up for those in the south:

The ensembles have shifted northwards, indeed some are quite alot further north on this 12z suite...

Only a couple are in the channel...

Whilst we are getting into the timeframe where the ensembles don't matter as much, its interesting to see there IS still quite a range of posiblities open.

Also worth noting the AROME ensembles earlier this morning also were north of its own run.

[sukayuonsensnow]

GFS12 today, that finger of colder air seems to head towards Scandinavia.

Might mean we risk a milder spell, however cooling down Scandinavia could make things interesting later. (especially If we get another easterly/northeasterly)

Of course again this is far out as weather goes, but I am looking closely at this development in the more medium term as it has been picked up a few times recently.

[Mike Poole]

5 minutes ago, feb1991blizzard said:

Still think we need a wide and far wave 2 split through Greenland or Iceland replicated all the way down the atmosphere, i think its differing viewpoints based on peoples threasholds for a buzz and being excited, i really cant get excited about snow which is gone by 2 hours like todays, i am looking for those insane setups with -15c uppers and gale force winds slamming through the country.

I disagree, we don’t need the pattern massively changed - we need the trop vortex to remain disturbed until we can home grow or import some proper cold, and that looks set to happen now, with the SSW when it happens part of the evolution.  

End of the GEM, not bad:

[XtremeUKWeather]

3 minutes ago, kold weather said:

Just a little heads up for those in the south:

The ensembles have shifted northwards, indeed some are quite alot further north on this 12z suite...

Only a couple are in the channel...

Whilst we are getting into the timeframe where the ensembles don't matter as much, its interesting to see there IS still quite a range of posiblities open.

Also worth noting the AROME ensembles earlier this morning also were north of its own run.

Wow , are the Arome ensembles public ?

[feb1991blizzard]

3 minutes ago, Mike Poole said:

I disagree, we don’t need the pattern massively changed - we need the trop vortex to remain disturbed until we can home grow or import some proper cold, and that looks set to happen now, with the SSW when it happens part of the evolution.  

End of the GEM, not bad:

TBF i must admit, this GEFS suite is going to be a snorter, small sample size, randomly picked about 5 members at  192 and i would suspect all of them would go on to show a significant snow event somewhere in low lying UK within 50-100 hours.

Edited December 29, 2020 by feb1991blizzard

[Battleground Snow]

6 minutes ago, Johnp said:

There seems to be numerous disturbances / cold pools crossing the  country over the next ten days, so I'd expect several 'surprise' snowfalls to turn up at short notice. 

The GFS precip charts often falsely look dry at this range. 

Yes agreed, I remember Matt H showing a graph, which had hardly any precipitation spikes on for the north for this week, and look how many features have popped up at short notice

[Matt H]

8 minutes ago, kold weather said:

Just a little heads up for those in the south:

The ensembles have shifted northwards, indeed some are quite alot further north on this 12z suite...

Only a couple are in the channel...

Whilst we are getting into the timeframe where the ensembles don't matter as much, its interesting to see there IS still quite a range of posiblities open.

Also worth noting the AROME ensembles earlier this morning also were north of its own run.

Yes, the GEFS 12z mean shows a fairly decent snow event in the south still tomorrow night, even to the south of the infamous M4! Some marginality in the SW though.

 

Edited December 29, 2020 by Frosty Winter