Model output discussion - winter proper underway

[Tracy Flick]

5 minutes ago, lassie23 said:

Don't usually post in here as I don't have a scooby about interpreting model output, but has the GFS been the model that picks out cold trends this winter, before any other model and the rest soon follow, or am I mistaken?

Well, I haven't been following much but by the sounds of it the EC model is being consistent in forecasting a flatter pattern, so if the models 'flip' (as suggested) it's a success for the GFS IMO... unfortunately if they don't the EC will be strutting like a peacock instead. 

(But the caveat is that much of the EC data is paywalled, so maybe the differences aren't as pronounced as they appear to be to us.)

Overnight developments have pushed the swing-o-meter more towards the EC I feel.  But hey what do I know.

[jvenge]

4 minutes ago, feb1991blizzard said:

46 dayer Northern Hemisphere charts will be available soon, still waiting for ECM strat charts (not so important as we get them next day anyway), still nothing about EPS strat charts though which would be helpful.

You mean the EPS 46 based on yesterdays 0z? They are out and there isn't anything of interest there for coldies. I personally have an incredibly low opinion of it, though.

[feb1991blizzard]

3 minutes ago, jvenge said:

You mean the EPS 46 based on yesterdays 0z? They are out and there isn't anything of interest there for coldies. I personally have an incredibly low opinion of it, though.

No, I mean we will be able to view them in Northern hemisphere format permanently soon, not sure how much data is going to be available.

[lassie23]

11 minutes ago, meh said:

Well, I haven't been following much but by the sounds of it the EC model is being consistent in forecasting a flatter pattern, so if the models 'flip' (as suggested) it's a success for the GFS IMO... unfortunately if they don't the EC will be strutting like a peacock instead. 

(But the caveat is that much of the EC data is paywalled, so maybe the differences aren't as pronounced as they appear to be to us.)

Overnight developments have pushed the swing-o-meter more towards the EC I feel.  But hey what do I know.

 

20 minutes ago, tight isobar said:

Gfs is great trend spotter..

Although has some issues as a trend setter!..

And can drop its evolutions as quick as applying them.

And given the current divergance...its a concern if cold is you favour.

However this mornings 6z and support 'should' now shed some light!?.

A big run this morning.

Thanks very much for your replies.

[beng]

Just to offer a bit of hope - this is a chart from 20th Dec 1970 -

 

there's a few similarities there in terms of the ridging on the US/Canadian West Coast and the Atlantic pattern too - relative to GFS forecasts (Joe B has been talking about 1970 a bit and you can see the broad-scale similarities).  BTW - I don't bother looking at the ECM op past 144-168h these days as rightly or wrongly I no longer trust it at this range since the last upgrade.

 

Here's how Christmas day 1970 looked:

 

 

I think what's been hampering us for a while though are the SSTs around the Azores which are still a bit above average -

that just doesn't help when it comes to splitting the jet and getting energy South into W Europe. I think we have the atmosphere wanting to play ball, but for the moment Atlantic SSTs are working against us being able to lock in a cold pattern. 

 

Edited December 15, 2017 by beng

[northwestsnow]

20 minutes ago, nick sussex said:

Operation Save Christmas suffers a heavy blow this morning!

The GFS 00hrs is at least better than the previous 18hrs run but not as amplified as the 12hrs.

The ECM is flatter than yesterdays 12hrs run.

The UKMO is dismal from a cold perspective, the flattest of all.

Okay that's the bad news out of the way!

The ECM ensembles  show a  spread through the UK in terms of temps and the pressure ones show the spread just to the east suggesting theres support for more amplification and low pressure digging south.

The problem remains in terms of Christmas that the models agree in pushing the PV south again and you need to have a strong ridge to the ne to help disrupt some of that upstream energy.

Save Christmas drops from 5/10 last night to 4/10 after the early outputs.

We need to see more amplification within the T168hrs timeframe as quickly as possible!

 

 

I was hoping for something so much better from EC this morning Nick.

Feel even more deflated after hearing the ext eps are +NAO.

As you say we need to see some amplification ....fast!

[Summer Sun]

UKMO extended keeps the high in charge (Dec 22nd)

GFS at the same time

 

Edited December 15, 2017 by Summer Sun

[Man With Beard]

There will be a big cluster on the EPS this morning with ridging towards Greenland on the 22nd December - possibly a majority of members getting high pressure all the way up to Greenland, with a better angle than shown on the mean for cold on the east flank.

By Christmas Day, though, flattened - 80% of members have a healthy Icelandic low.

Not much change between Christmas and New Year according to this ensemble run, either - 70% milder / 30% colder split (rough estimates).

 

[carinthian]

1 hour ago, carinthian said:

Looks like GFS evolution at T10 on its own. Still wants to lower heights into Western Europe. ECM and GEM retaining heights over Europe and a more milder westerly flow into Northern Latitudes. UKMO looks at this stage (144t ) could be siding with the ECM model but possible with a different longer term outcome. Usually GFS is the trend setter at 240 T so we will all have to sit and wait and see  for any major adjustments or back downs with later runs. Just for interest the chart from GFS for the New Year looks snowy for North Western Europe with a substantial trough alignment. Just shows you can get cold and snow in Northwest Europe with out a freezing cold Russia as here they have above normal temps with abnormal Rossby Wave pattern in place.

C

The American Navy Model also shows less amplification at 180t. So looks like GFS out on its own at this stage. Good luck with its trend setter from my cold preference to evolve. We will know later with the next 2 runs whether it strengthens it output towards that scenario or backs away big style .

 C

[northwestsnow]

Just now, Summer Sun said:

UKMO extended keeps the high in charge (Dec 22nd)

 

Looks dry at least-

Saw your tweet post about chris fawkes suggesting EC now 'off board ' again (for coldies)...

Ec does seem to be all over the place at present, wonder what has caused it to go so flat this morning....

Lets hope it doesn't settle on the 'off board' signal!!

[northwestsnow]

2 minutes ago, Man With Beard said:

There will be a big cluster on the EPS this morning with ridging towards Greenland on the 22nd December - possibly a majority of members getting high pressure all the way up to Greenland, with a better angle than shown on the mean for cold on the east flank.

By Christmas Day, though, flattened - 80% of members have a healthy Icelandic low.

Not much change between Christmas and New Year according to this ensemble run, either - 70% milder / 30% colder split (rough estimates).

 

Urgh!

70% milder between christmas and new year !!!

Lets hope the trend improves hereon in

[ArHu3]

1 hour ago, mulzy said:

The extended eps looks very mobile - positive NAO.  Not overly mild but no significant cold signal.

The De Bilt ensemble is showing a lot more cold members after Christmas, with mainly (s) easterlies and a few North easterlies, they weren't there yesterday 

 

 

 

 

Edited December 15, 2017 by ArHu3

[tight isobar]

8 minutes ago, carinthian said:

The American Navy Model also shows less amplification at 180t. So looks like GFS out on its own at this stage. Good luck with its trend setter from my cold preference to evolve. We will know later with the next 2 runs whether it strengthens it output towards that scenario or backs away big style .

 C

Couldn'nt have put it better myself -C-

GFS certainly out on its own..and if it pulls this one-ahead of other output its an outstanding acheive!

To reiterate/some huge runs on the table today...6z/12z.....

Edited December 15, 2017 by tight isobar

[Hocus Pocus]

My tuppence worth (not that it’s worth much ) is the models continue to struggle with the upstream pattern post Xmas offering  a variety of solutions within the ensembles. One only has to look at the MetO updates to see the wide range of scatter on offer so it’s no good following every single run as if your life depended on it, just sit back, watch with interest and try to spot these upstream signals without the emotive outbursts on each and every run. Back to the sidelines for me.

[TEITS]

I find the difference between GFS & other models fasinating. Yet again we see the GFS Op run supported by the GEFS control.

For the sake of everyones sanity it is best to assume the GFS is wrong and that Xmas is likely to be mild. However I certainly wouldn't be willing to bet on this just yet!

Beyond Xmas and I shall repeat myself by saying a return to a colder pattern is much more likely to come from N/NW than the NE/E.

[northwestsnow]

5 minutes ago, TEITS said:

I find the difference between GFS & other models fasinating. Yet again we see the GFS Op run supported by the GEFS control.

For the sake of everyones sanity it is best to assume the GFS is wrong and that Xmas is likely to be mild. However I certainly wouldn't be willing to bet on this just yet!

Beyond Xmas and I shall repeat myself by saying a return to a colder pattern is much more likely to come from N/NW than the NE/E.

Think all the coldies are in the GFS corner this morning Teits...

EC wants to push the PV back to Greenland by day 10!

ps i agree regarding the north west

Edited December 15, 2017 by northwestsnow

[feb1991blizzard]

4 minutes ago, TEITS said:

I find the difference between GFS & other models fasinating. Yet again we see the GFS Op run supported by the GEFS control.

For the sake of everyones sanity it is best to assume the GFS is wrong and that Xmas is likely to be mild. However I certainly wouldn't be willing to bet on this just yet!

Beyond Xmas and I shall repeat myself by saying a return to a colder pattern is much more likely to come from N/NW than the NE/E.

Depends, the initial dig of the Jet may bring PM air but any sustained cold is likely to come from the East in my opinion, the Canadian segment of the vortex will push into Greenland thus unable to build greeny heights IMO - Xmas is nailed on to be a not white in London IMO - already backed it at low odds.

[comet]

While the gefs show charts like the one's below then there is still plenty to play for plus the gfs 0z op run is not to shabby at all.

Edited December 15, 2017 by comet

[northwestsnow]

5 minutes ago, feb1991blizzard said:

Depends, the initial dig of the Jet may bring PM air but any sustained cold is likely to come from the East in my opinion, the Canadian segment of the vortex will push into Greenland thus unable to build greeny heights IMO - Xmas is nailed on to be a not white in London IMO - already backed it at low odds.

Think i can see where teits is coming from - heights rises behind the Atlantic jet digging SE into Europe- its something i was pondering yesterday.

Personally (unless you believe GFS) i feel height rises to our NE is fast becoming unlikely anytime soon.

Either way unless we see height rises in the north Atlantic or scandy it looks like becoming unsettled now between xmas and new year.

Lets hope for upgrades- esp from EC!

Edited December 15, 2017 by northwestsnow

[Chesil View]

Guys hasn't the post Christmas into new year period always been the time for a suggested pattern change why is it all of a sudden everyone hung up on the pattern not showing xmas day for heavens sake get a grip 

Edited December 15, 2017 by Broadmayne blizzard

[feb1991blizzard]

Just now, northwestsnow said:

Think i can see where teits is coming from - heights rises behind the Atlantic jet digging SE into Europe- its something i was pondering yesterday.

Personally (unless you believe GFS) i feel height rises to our NE is fast becoming unlikely anytime soon.

Either way unless we height rises in the north Atlantic or scandy it looks like becoming unsettled now between xmas and new year.

Lets hope for upgrades- esp from EC!

Important not to get wires crossed here, depends what you call soon, as ive said already with my bet, anyone hoping for anything in the xmas period is likely to be disappointed, I'm looking into week 3 before any potent air reaches us and that depends on the orientation of any blocking and availability of cold air to tap into.

[swfc]

Yesterdays meto long term update in regard to late dec-jan on regard to colder than average temps ete.if the models are switching or not surely there predictions are based on more than a few gfs runs ete.if today they water down that forecast where does that leave extended forecasts! !!!

Personally I think a dry cold-cool xmas is on the cards with a mlb

[northwestsnow]

6Z rolling out now.

Will be interesting to see if it mantains the cold signal post xmas

[TEITS]

Less amplified 06Z which isn't surprising.

[tight isobar]

4 minutes ago, TEITS said:

Less amplified 06Z which isn't surprising.

Certainly less atlantic -amp..6z

See where it goes from here!