Model Output Discussion - cold spell to end Autumn

[Daniel*]

43 minutes ago, daz_4 said:

Please, the warming at 380 has been there for at least ten days now. It is not getting closer. And yes, looks like the vortex will rebound.

Have you a seen D10 on EC though 

Quite a significant warming at 10hPa NW of Greenland. Oops ignore not temps..

Going foward I don’t quite know what to make of it others on here perhaps can dissect, it may encourage a more active Atlantic profile but with quite a southerly tracking jet stream... However, on a postive I firmly doubt the vortex will be making its home in Greenland anytime soon? I’m unsure what the verification stats are like at D10 but they are better because they do not deal with the oceans etc.

Edited November 30, 2017 by Daniel*

[Scandinavian High.]

4 minutes ago, blizzard81 said:

I notice that members are avoiding any mention of the possibility of an easterly post day 10. I for one think that the chance of one has increased over the last 24 hours. The block to the east is growing and the displacement of the azores high will encourage lows to dive south east into western Europe and undercut the ever growing block to the north east. 

Agreed didn’t someone  mention this the  other day  high building to the north east battleground Britain I think ukmo  mentioned  this in there outlook something to keep an eye on maybe.

[mountain shadow]

Good forecast Nick but I'm struggling to see  -NAO in the model output.

[nick sussex]

8 minutes ago, Frosty. said:

Tragic beyond belief is usual for UK coldies in winter..hope you're right nick..I want to see what you do when we reach white alert!

I'm not promising a big freeze but the upstream pattern and neg AO suggest a low track se'wards into the UK which always gives opportunities for some snow and cold.

MS re the neg NAO that has been difficult to achieve in recent years.

We'll have to see over coming days whether the outputs deliver that.

 

Edited November 30, 2017 by nick sussex

[January Snowstorm]

We should be well versed at this stage on how the UK and Ireland can find a route to mild even when all roads say cold. The last few days have been disappointing and chasing snow on these shores can be heart wrenching at times. Saying that our obsession with snow is pbly borne out by the fact that it really is like the holy grail lol

The background signals are all good for December and it's only a matter of time before the models pick up on it. As we know they have a pattern of over correcting when a change is picked up.

[stainesbloke]

13 minutes ago, blizzard81 said:

I notice that members are avoiding any mention of the possibility of an easterly post day 10. I for one think that the chance of one has increased over the last 24 hours. The block to the east is growing and the displacement of the azores high will encourage lows to dive south east into western Europe and undercut the ever growing block to the north east. 

A southerly tracking jet with a more active Atlantic may well end up acting favourably for chances of cold and snow for the UK. An easterly could be the result, ideally the continent will be colder than now. An interesting period of model watching, though personally I'd rather the snow came after Christmas.

[knocker]

16 minutes ago, Frosty. said:

Tragic beyond belief is usual for UK coldies in winter..hope you're right nick..I want to see what you do when we reach white alert!

I can think of many things that are tragic beyond belief, or even tragic on it's own, but disappointed obsessive chionophiles is certainly not one one them Actually it borders more on the hilarious. It would give a Greek Tragedy a run for it's money in here on occasions.

Edited November 30, 2017 by knocker

[chicken soup]

23 minutes ago, nick sussex said:

The updated NOAA monthly forecast has just been issued.

http://www.cpc.ncep.noaa.gov/products/predictions/long_range/fxus07.html

If the UK can't get some snow and cold from what I've read then theres a curse!

It might be wintry in the east USA with energy firing east into the Atlantic but with a negative AO and the MJO on the move towards the west Pacific low track into the UK should be forced further south.

So to be frank it would be tragic beyond belief if coldies here don't get something to enjoy during December.

Tragic beyond belief is I'm afraid the usual and expected outcome for uk coldies.

[nick sussex]

4 minutes ago, knocker said:

I can think of many things that are tragic beyond belief, or even tragic on it's own, but disappointed obsessive chionophiles is certainly not one one them Actually it borders more on the hilarious. It would give a Greek Tragedy a run for it's money in here on occasions.

Blame me its my melodramatic posting style! Talking of which as you know my heritage is Greek Cypriot so it comes naturally!

[Frosty.]

1 minute ago, chicken soup said:

Tragic beyond belief is I'm afraid the usual and expected outcome for uk coldies.

Is there an echo in here, I already said that above

Anyway, a massive 18z is looming large

[chicken soup]

Just now, Frosty. said:

Is there an echo in here, I already said that above

Anyway, a massive 18z is looming large

hadn't read your post

 

[Froze were the Days]

12 minutes ago, stainesbloke said:

A southerly tracking jet with a more active Atlantic may well end up acting favourably for chances of cold and snow for the UK. An easterly could be the result, ideally the continent will be colder than now. An interesting period of model watching, though personally I'd rather the snow came after Christmas.

Hints at times on the CFSv2 monthly model of a Siberian / Scandinavian high pressure showing it's face towards mid-December, I should say over the last couple of days.

[Polar Maritime]

Just sensible discussion please.

Thanks.

[I remember Atlantic 252]

606 ish hours until Xmas, a horrid one too

[ribster]

1 minute ago, I remember Atlantic 252 said:

606 ish hours until Xmas, a horrid one too

If that chart verifies you can have my salary! 

[bluearmy]

The extended eps continue where the higher res leave them at day 10. A continuation of low sceuro height and slp anomoly and low uppers anomoly which fully encompasses the uk. Mean jet angled nw/se across sw uk with the ne pretty well clear of it. Broad European trough maintained. I have also spotted the gefs generally raising heights to our ne through week 2. I guess whilst the output does seem to lack continuity, the general message of strong Atlantic jet nw/se is still there and a whole gamut of options remain on the table re the outcome for our little island. 

a cold first half of December seems likely but could end up chilly wet, frosty dry or a mixture of both which could lead to some  of the white stuff.  Not sure what to make of the gfs/gefs wanting to restore a stronger zonal flow higher up in the strat later week 2. ecm looks just as blocked up there at day 10 and the trop pattern still looks very split which will promote more wave breaking from the trop

[weirpig]

1 minute ago, I remember Atlantic 252 said:

606 ish hours until Xmas, a horrid one too

Quality post. The models are unsure what happend an hour ago never mind Christmas  but of course if it was showing a white Christmas  that would be a different matter .   Anyway 18z due I expect an upgrade  keeping an eye out for shortwave movement

[terrier]

Well with the gfs pub run upon us and with the gfs trailing 5th in the verification stats I certainly wouldn’t be backing my wage on it 

[booferking]

48 minutes ago, Summer Sun said:

UKMO extended wet and windy

Yes but much like Gfs 6z once that low clears we should have a Northerly with cold air digging in yes no??

[Methuselah]

12 minutes ago, Frosty. said:

Is there an echo in here, I already said that above

Anyway, a massive 18z is looming large

Keep an eye out for the ginormous blizzard on day 10?

[summer blizzard]

1 hour ago, nick sussex said:

Frustratingly the MJO forecasts haven’t updated for two days . Very bad timing for that to happen .

We might be seeing some conflicting messages in the outputs and more volatility than normal .

This displaced Azores high in the ECM  has me wondering.

This may suggest some movement east/higher amplitude from the GFS MJO forecast.

Whether it will get past those trades is another question though..

[bobbydog]

56 minutes ago, daz_4 said:

Please, the warming at 380 has been there for at least ten days now. It is not getting closer. And yes, looks like the vortex will rebound.

that warming at 384 is a new one. the first chart is the one that's "been there at least ten days" and thats at 144, which incidentally never reached the upper strat and was not really modelled to. i do actually watch the charts on a daily basis so i'm not just posting 'hopeful' charts. maybe you should study the output more carefully then you might have seen the progress these 'warmings' have been making and that chart you posted is updated twice a day, based on the 00z and 12z GFS runs. 

so "please" check your facts before attempting to be condescending.

[Man With Beard]

Seems slightly futile considering the ECM op is behaving like a 5 year old trying to play darts ... But if you want to know where the ECM would have gone next, the control run is very similar at D10. It quickly sinks the trough into the centre of Europe with a weak NE flow behind it, encouraging cold continental air towards NW Europe. As for the UK, well, troughs thereafter dive through the gap between high pressure to the NE and high pressure to the SW, leading to lots of snow where the fronts hit the cold.

In other words, the chase may go on whether we get the northerly next week or not!

Edited November 30, 2017 by Man With Beard

[JBMWeatherForever]

Maybe just maybe, this time, what will be beyond belief, will be potency of the northerly's and the excitement of the wonderfully cold synoptics, that we enjoy during the month of December 2017. 

[damianslaw]

The northern hemispheric base state remains a static one for the foreseeable, no sudden changes afoot, hence the outlook is more than likely to be more of the same until we see clear signals of a major pattern shift.

What this means is the continuation of an amplified flow, azores high advected NW towards mid atlantic, and a jetstream rather split and diffuse with more energy transferred into the southern arm than the northern, hence the UK mostly locked on the colder side, with trough aligned NW-SE, but with some temporary breaks, as we are about to see this weekend and into next week.

All the while heights remain very strong over the North Pole, and a deep longwave trough is setting up through central/east Canada and into east USA, how this then engages with the jetstream is key to developments over here. It isn't perhaps a surprise to see the models showing quite a sudden development of low heights courtesy of shortwave activity spawning from this trough, interacting with the jetstream and ushering in quite an unsettled spell later next week, the explosion of activity aided by the sharp temp gradient caused by the ever cooling arctic and still milder than usual mid atlantic. However, the models are often pre-disposed to suggesting a very energetic atlantic in such situations, but the balance is against any quick return to zonality, and there are very fine margins being played here - the forcing is all on the trough over the UK, and the power of heights to the north, the path for the trough looks destined for central europe, and in time this could allow significant heights to build out of N Russia and towards Scandi - so I wouldn't be surprised to see some of the long range models playing with an easterly, equally wouldn't be surprised to see them showing a resurgent atlantic, but the likely outcome probably neither, and instead we should expect more in the way of polar/arctic maritime air.