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Model Output Discussion - 31/10/2014 and Beyond


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Indeed, is the ECM having another moment ? We will know by the end of tomorrow.

If this resembles the Dec 2012 ECM fiasco, we really do need to re evaluate our opinion

of the ECM and it's accuracy post 6 days. I know one thing for sure - the ECM was not prone

to wild swings so much pre 2012. The wild swings were confined to the GFS. Has ECM caught

the disease over the last couple of years ? Or is it going to prove it's position as the best ranked model

over the next couple of days ? These are the questions  :cc_confused:

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Its the 18z. No one with any credibility even bothers with it- same as the 6z, plus then you factor in the fact the GFS cannot resolve any high Pressure over Scandi & moves the jet through it rather than over it then im afraid its standard GFS fair im afraid...

 

give the GFS another 18 hours to the 12z tomorrow or poss 30 hours till the 00z Monday before it fully catches up-

 

Night all.

 

S

 

Given the Polar Jet is the ribbon of maximum thermal gradient between the cold and warm air (a very simplistic definition of a complex subject) what has running over or though high pressure got to do with the price of fish? Are you suggesting the GFS get's the vertical placement and orientation of the jet wrong?

Edited by knocker
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Its the 18z. No one with any credibility even bothers with it- same as the 6z, plus then you factor in the fact the GFS cannot resolve any high Pressure over Scandi & moves the jet through it rather than over it then im afraid its standard GFS fair im afraid...

 

give the GFS another 18 hours to the 12z tomorrow or poss 30 hours till the 00z Monday before it fully catches up-

 

Night all.

 

S

So the GFS parallel (ie the new GFS) is as rubbish as the old one?

The OPI team certainly bothered with the 06z, do they have no credibility?

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I seem to remember a mild period (Didn't we just hit 24*C last week) before a fairly wet period with the models counting down for two weeks showing northern blocking. Re: November 2010

Easterlies/Northerly before throwing away the idea then coming back with something even bigger.

I am intrigued by the similarities of the two months thus far.

Edited by Robbie Garrett
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Personally I would be tempted to back the gfs on this occasion ties in well with the met office outlook.still think the ECM is too progressive. Expect it to back down towards gfs over next few runs.

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Given the Polar Jet is the ribbon of maximum thermal gradient between the cold and warm air (a very simplistic definition of a complex subject) what has running over or though high pressure got to do with the price of fish? Are you suggesting the GFS get's the vertical placement and orientation of the jet wrong?

I think "over" means "to the north"?

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Indeed, is the ECM having another moment ? We will know by the end of tomorrow.

If this resembles the Dec 2012 ECM fiasco, we really do need to re evaluate our opinion

of the ECM and it's accuracy post 6 days. I know one thing for sure - the ECM was not prone

to wild swings so much pre 2012. The wild swings were confined to the GFS. Has ECM caught

the disease over the last couple of years ? Or is it going to prove it's position as the best ranked model

over the next couple of days ? These are the questions  :cc_confused:

The trouble I've had the last 36 months is ECM often messes up Greenland and GFS messes up Scandinavia, IMO. So without agreement from the two, you've got to be cautious with both of them in this kind of scenario, since the interaction between Greenland and Scandi is crucial.
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Hi Knocker, 

I think Steve is alluding to the Bias the GFS has for flattening a Scandi High, and its reluctance to have any heights in or around our neck of the woods. 

 

The GFS IS poor at handling heights, even a Scandi one, as seen so many times in summer as well... but as i`m sure you are aware from experience heights are always underestimated where the GFS is concerned. 

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So if it's poor at handling heights, from a meteorological point of view, what does it mean it's poor at handling?

 

Edit. What I'm attempting to say is this. If you have a 250mb contour chart showing HP over Scandinavia say, even if the GFS misrepresents the thermal structure of the airmass and thus the heights, the jet will still follow the contour lines. As the contour lines (heights) are a function of temperature it follows that the area where they are closer together (highest thermal gradient) you will find the jet. It also means, for obvious reasons, that great care should be taken if you are transposing the position of the jet on to a 500mb chart.

 

An example from this morning where the jet passes north of the mid Atlantic ridge and then splits and runs around the upper low and then the HP

 

Conclusion

moving the jet through HP = nonsense

post-12275-0-30939100-1415511701_thumb.p

Edited by knocker
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I reckon we will see some cold eventually, I'm going to go for mid December though. It seems to be being pushed back a little. Still very good Synoptics of the smashed PV, which greatly increases the chance of cold spells. The building blocks are certainly there, that's for sure.

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I remember last winter, not too fondly I will add. The ECM would show 'interest' post day 5/6, ... only for it to fail or completely swing to a different solution on the next run. It's the same old.... the usual suspects ramping an ecm, based on nothing more than personal preference and hope. And we will never learn! Its like deja vu. GFS criticised, pulled apart etc. But the Global Forecast System was the model winner last winter. The ECM failed northerly last Dec (if memory serves).... the GFS never got fully onboard, and we saw the EC back down as we got closer and closer to the critical juncture.

 

While the synoptics are different this Nov, I fear we are getting far too ahead of ourselves, as always. 

 

4u9yj9.png

temp anom indicates we are along way from any 'meaningful' cold. Usual caveats apply, of course :)

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the first charts i view every morning are the anomaly charts, because as john holmes has championed, when they are in consistent agreement then they are pretty accurate (about 80% i think the figue was) of being right 6-14 days ahead.

 

so

 

post-2797-0-40888100-1415516472_thumb.gi post-2797-0-75786900-1415516486_thumb.gi

 

post-2797-0-44160500-1415516511_thumb.gi

 

are in and have been in consistent agreement, so charts like these from the gfs and ecm @t168 look accurate.

 

post-2797-0-39109000-1415516586_thumb.gi post-2797-0-26524900-1415516602_thumb.gi

 

further out though is where both models struggle, and this chart the ecm 12z @t240 simply cannot happen as long as the anomaly charts stay as they are. nor do they currently allow for a deep easterly. they might change, but until they do....

 

post-2797-0-39128300-1415516687_thumb.gi

 

the gfs in deep fi continues to suggest highs to our northeast

 

post-2797-0-44871300-1415516883_thumb.gi

 

but as the uppers show, even cold looking surface charts often arent. (i use the 850's instead of surface... they do give a clearer picture of likely temp profiles)

ignore the agreeing anomaly charts at your peril....

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ECM 0z is all championing the easterly.....three runs in a row now.

I don't expect any snow this month, but it is great to see some intent for possible colder conditions from the models after last year.

btw the knocker vs. SM battle is a little boring now.

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GFS 0z not to bad at 192, Stronger heights in Scandinavia and Greenland, and even small heights in the Atlantic. Maybe some steps towards the ECM. Just wondering now if the ECM sticks to it's guns.

 

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=192&mode=0&cart

well the ecm looks incredible but is still on its own against all the other models.

its close but no cigar the whole retrogression on all but the ecm declines after a brief visit to greenland.

 

not one of the other main models are showing what the ecm is lovely eye candy but just no support im afriad its a waiting game.

still a good hemispheric pattern but got a gut feeling things are starting to move away from over a week of excitement.

 

ecm 144

ECH1-144.GIF?09-12

gfs 144

gfs-0-144.png?0

gfs para

gfs-0-144.png?0

ukmo 144

UW144-21.GIF?09-06

you can see why the met office have given a 10% chance its perfectly clear why!...

 

gem 144

gem-0-144.png?00

gefs 144

gens-0-1-144.png?0

 

its simple to see the ecm is way way over progressive and this happens so much be nice to see the heights bias removed from this model.

although still a good model out to 144 but even with in this time frame its still prone to height bias.

 

i think novemeber is a no go for any ecm winter type chart.

although i still hold high hopes for dec but a little on the fence.

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The GEFS are now showing a clear trend towards the PV recovering by D16 as the shock from the Pacific storm gradually subsides. Nearly all at D16 lose the HLB and the MLB are now in the clear minority. So despite ECM showing potential building blocks, based on the current GEFS the PV will not give it the time it needs:

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=384.

 

There was about 9 members that show at D10 some inclination towards the ECM and a few lead to a cold flow late in FI.

 

Of course the LR GEFS may be wrong but as a current guide they are not great for prospects going forward. It was an unusually early shot at Winter and seemingly a miss for the UK but another direct hit for the US.

 

GEM at D10 is rather more like GFS Parallel than ECMpost-14819-0-58493300-1415516489_thumb.p post-14819-0-75591200-1415516499_thumb.p

Though more WAA on the GEM (though GEM is even more bias to heights than ECM in the NH). GFS P in FI is rather uninspiring, with a block to the east and the jet taking a left turn as it hits the UK=Rain:

 

post-14819-0-42165100-1415516675_thumb.p  Looking at the GEFS for London just a normal profile for mid November: post-14819-0-89751400-1415517098_thumb.g

 

Comparing the ECM at D10 from last night you can see it has taken a big step towards the GFS with substantially less HLB and no cross flow, which will come as no surprise to many:

 

12z last night: post-14819-0-84184600-1415517203_thumb.p  Today: post-14819-0-77154800-1415517221_thumb.p

 

With the ECM stratosphere wave 2 activity looking like a false dawn we just have to hope that this meridional flow has not just delayed the inevitable PV onslaught. Certainly no sign of any sustained cold for the next 14 days for the UK.

 

 

 

 

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Excellent post there I'm Dreaming, With Cross-Model Analysis  ^

 

Once again the ECMWF is showing an Easterly towards the end of the run. GFSP also hinting this, But showing the Atlantic winning out again. So still a very weak signal, And the uncertainty regarding this continues. Next week shows plenty of wet/cool weather, With bands of showery/persistent rain spreading in from the N/W over the UK.

 

R.I.P to all the brave that have fallen, Lest We Forget.

 

lest%20we%20forget.jpg

 

ECH1-216.GIF?09-12gfsnh-0-228.png?0gfsnh-0-384.png?0

Edited by Polar Maritime
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http://www.meteociel.fr/modeles/gefs_cartes.php?code=16&ech=192&carte=&mode=0

 

well  its looking good in f1 for the beastly  eastly dare  i say it !!!

i cant see nothing on any of these charts????????

excellent post this really is a reality check !

incredibly the arctic profile seems to be decreasing before our very eyes.

 

and as has been suggested in the post above the pv is trying to regain its title of the winter reaper.

 

i did suggest last night that its possible that the vortex will make a come back, but its not over still interesting to see where this heads into dec.

 

but suggestions where jan and feb for the better chances.

 

the only saving grace could be that heights seem to be lowering into europe and the jet although not south enough is still better than this time last year and not as strong.

gfs-5-144.png?0

 

fax120s.gif?0

 

we need heights much lower into europe and this is one reason why the whole pattern being shown recently is likely to fail.

close but no cigar.

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Couple of things (again)

ID - strange that you feel the gefs show the vortex getting its act together by the end of week 2. My take on looking through them was that we are unlikely to start December with an organised compact trop p/v in place!

the London temps from yesterday's 12z ens suite would indicate that Exeter would raise the likelihood of an easterly to at least 20% this morning.

there is no sign that the upper strat vortex will get any respite from the Asian warmings. that should ensure the trop vortex struggles to gain traction for some time.

and yes, ECM op is likely over amplified as per usual. The trick is working out where. The differences over the pole with the movement of the arctic high seem to be the main difference in the mid term with obvious consequences thereafter. Ukmo just about getting in range of this so we should get a feel over the next couple runs for where this is going. It still looks like the coldest uppers will miss us to the north for the time being if the broad ECM op solution is close to verifying.

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i did suggest the last night that after the unsettled spell showing across the models that in time towards the end of nov there could well be height rises into the uk bringing frosty cold surface conditions and this chart although a lot of scatter is suggesting this is possible.

 

prmslLondon.png

t2mLondon.png

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The GEFS are now showing a clear trend towards the PV recovering by D16 as the shock from the Pacific storm gradually subsides. Nearly all at D16 lose the HLB and the MLB are now in the clear minority. So despite ECM showing potential building blocks, based on the current GEFS the PV will not give it the time it needs:

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=384.

 

So this will be the SEVENTH time that the GFS has tried to build a strong PV since the start of October. Current success rate: 0 out of 6. 7th time lucky? (and I really do mean 'lucky')

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A quick run through of the GEFS anomaly this morning. (quite boring really)

 

D10 has the Alaskan and Greenland ridges with a pretty well organised PV but with an intense low NE Canada. The evolution of this plays a significant role in later frames. So although there are indications of higher heights into N. Britain this gives away to the Atlantic. Temps still generally above average.

Charts courtesy WxBell

post-12275-0-38230400-1415520878_thumb.p

post-12275-0-69465900-1415520885_thumb.p

post-12275-0-59734000-1415520893_thumb.p

post-12275-0-29236400-1415520901_thumb.p

post-12275-0-87187900-1415520910_thumb.p

post-12275-0-54192000-1415520919_thumb.p

post-12275-0-90141200-1415520929_thumb.p

Edited by knocker
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