Model Output Discussion - The Run In To Christmas

[That ECM]

Hi Nick, like I said though, it is the second 12z op on the trot to insist on the low in the atlantic splitting the high and heading straight for us. The ECM has a knack of spotting a trend even at 8 to 10 days that the other models don't even sniff. I fear this is one of those occasions unfortunately. The met seem to be agreeing with this scenario as well.

I get what your saying and it's not as good as the gfs but if we were at t240 on the ecm would that be the worst place to start.

[karlos1983]

I've just posted in the ramp thread that Ian F mentioned the Christmas Period on the local forecast, and made the point that there is unlikely to be anything wintry over Christmas, just alternating between mild & cold between now and the big day, with the run up to Christmas being mild.

 

But he was only talking about of local though.....

Well the Met have been proved to be wrong on many occasions and are always the last to join the party and let the public know its going to be cold/wintry. But they have to be pretty certain when they come out with such statements as it feeds straight into the public domain! They probably find it far easier to sit on the fence this far out and give a broad brush average kind of outlook.

What they say isn't the gospel, or we wouldn't be here! And that is no disrespect to Ian F.

The fact is that the models available for us to see are all trending to something Colder and more blocked, which I personally am enjoying viewing ALOT!

[nick sussex]

Hi Nick, like I said though, it is the second 12z op on the trot to insist on the low in the atlantic splitting the high and heading straight for us. The ECM has a knack of spotting a trend even at 8 to 10 days that the other models don't even sniff. I fear this is one of those occasions unfortunately. The met seem to be agreeing with this scenario as well.

Future output may send it a bit more ene/east or leave it as a cut off feature. The ECM makes the worst possible phase point, it might be phasing occurs further south.

 

It's at T216hrs and theres a lot of outputs to get through so I think we need to see how things develop, not worth worrying about too much at this stage.

[Winter Cold]

Seven pages to read last night, seven pages again this morning....and now 7 pages of a new thread in 5 hours!   Ive got that fuzzy excited feeling you can only get from this forum when the models show cold in winter marvelous!!

 

I do agree the GFS seems to be better over Greenland than ECM and its been quite consistent in all its runs for the past few days now for a cold period to start. Lets just hope its in time for the big day.

 

Things are looking good, even if its after Christmas, then our first snow (for most) in nearly 2 years might not be far away!

[Long haul to mild]

Hi Nick, like I said though, it is the second 12z op on the trot to insist on the low in the atlantic splitting the high and heading straight for us. The ECM has a knack of spotting a trend even at 8 to 10 days that the other models don't even sniff. I fear this is one of those occasions unfortunately. The met seem to be agreeing with this scenario as well.

I don't have much faith in any model beyond 6 days when it comes to that level of detail and I lost even more belief in the ECM after leading us up the garden path with a few cold runs in November that never materialised.

Yes, there is always the risk of a good cold setup being messed up by something like the ECM shows but for me, two runs isn't enough to start being overly concerned.

In fact you could say that the GFS P is equally bullish about a very cold spell between Xmas and New Year and has been showing it for more than just a couple of runs.

As always, time will tell but I no longer think that the ECM is all-conquering. As for the Met, they have signified that there is uncertainty about the synoptics at that range, as there always will be. They are not likely to start ramping up events nearly two weeks away.

Seems like my glass is definitely half full!

Edited December 17, 2014 by Long haul to mild

[blizzard81]

I get what your saying and it's not as good as the gfs but if we were at t240 on the ecm would that be the worst place to start.

Yes, as long as the trend is not to move everything westwards and we arrive at a west based negative NAO. I guess I have been scarred too many times lol. The ECM is teetering on the brink of west based neg nao.

Edited December 17, 2014 by blizzard81

[SMU]

ECM day 9 MEAN

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/EDH1-216.GIF?17-0

 

the day 10 MEAN is almost identical to the GFS (p)

http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/EDH1-240.GIF?17-0

 

SOLID.

[The Eagle]

Very strong ECM ensemble average for increasingly cold from Christmas eve.

[That ECM]

Yes, as long as the trend is not to move everything westwards and we arrive at a west based NAO. I guess I have been scarred too many times lol. The ECM is teetering on the brink of west based neg nao.

It is my belief that the models move things slight further East as we get nearer to T0 more often than west but I cant back that up with stats just from what I recall.

[LomondSnowstorm]

Lovely ECM mean tonight, there'll definitely be something very wrong with the clusters if it shows mild southwesterlies and no Greenland ridge this time :

      

Edited December 17, 2014 by LomondSnowstorm

[SE Blizzards]

Just a quick reminder just how spectacularly wrong the ECM can be at Day 10....

 

Here is what the ECM was predicting on Nov 8th for Day 10

 

 

 

 

If i remember correctly, one or two (me included if i'm honest) were getting a little excited.

 

But..... the actually chart that verified for that day....

 

 

Completely and utterly wrong!

 

Of course, this is just one example, but to be honest there have been many many more examples like that which have happened over the last few months with regards to this model. Like Nick S said earlier, it really has been all over the place in it's predictions way out in la la land for quite some time now, and that's why i'd be very wary of what it is showing in FI. It may be the 'daddy' when it comes to weather models, but just like the rest of them, it does have it's flaws.

Edited December 17, 2014 by SE Blizzards

[MR EXTREMES]

I've just posted in the ramp thread that Ian F mentioned the Christmas Period on the local forecast, and made the point that there is unlikely to be anything wintry over Christmas, just alternating between mild & cold between now and the big day, with the run up to Christmas being mild.

 

But he was only talking about of local though.....

But to be fair Jo weather video on here suggests the same as Ian f evening bulletin!.

The met office job is to provide an accurate forecast for many different reason so really there doing just that.

Although if it's left to long to get a nation prepared it can cause alsorts of problems with out the fact lives could be at risk,

So there for to jump the gun to soon causes problems and to leave it to long is also risky so they meet in the middle when broadcasting.

And the bcc only do 5 day although they do hint when something's afoot!.

Really it also depends on the broadcaster whether there bothered if they take the flack for miss guided information from a weather model.

[Captain Shortwave]

ECM ens message, too late for a white Christmas most likely. Day 9/10 scream pre-new year cold blast from the north or north east. Anything to ruin my planned night out on the 29th 

[BlueHedgehog074]

Not sure how many comments (if any at all) regarding the 12Z JMA model tonight, but seems to go for a chilly Northerly on Christmas Day

Perhaps a chance, there, for some wintry showers towards Northern areas and perhaps down to some Western coasts. The -4*C 850 hPa temperatures just about covering the whole of the UK, too, though the even colder 850mb temperatures over Northern Scotland should ensure any wintry showers fall to low levels there. So in some ways, similar to some other models with some kind of amplification to the West. But as others say, some of the little developing Lows or Shortwaves, especially around Iceland, may need to be kept an eye on as they could delay any possible cold weather pattern (though I guess it ain't worth going into too much detail yet).

The ECM can just do one as its been getting on my nerves for the autumn and winter so far, I've erased its annoying output from my memory and will remain resolutely positive!

PS This will be my last tirade sometimes you just have to say whats on your mind.

PSS Unless that is the ECM gets on my nerves again in the morning!

I think we need one of the cold and snow fans to hack the ECMWF tomorrow morning, so then hopefully by the time it comes out, you won't be disappointed... Edited December 17, 2014 by DiagonalRedLine
To correct some big mistakes

[Polar Maritime]

Nice to to see the ECM & GFSP both singing from the same hymn sheet. Will be interesting over the next few days as the models firm up on detail. Very promising signs for a cold/snowy festive period.

 

Edited December 17, 2014 by Polar Maritime

[Nick L]

Lovely ECM mean tonight, there'll definitely be something very wrong with the clusters if it shows mild southwesterlies and no Greenland ridge this time :

      

 

The clusters didn't show mild southwesterlies last night, certainly not the ones I was looking at!

[damianslaw]

I was looking at charts of yesteryear - December 2000, very similar synoptics being shown for the Christmas period as we saw then, uncannily familiar, though we will be starting from a different situation. In Dec 2000 we did see shortwave activity but it simply led to heavy snow in many places with the cold staying in place until New Year. Shortwave activity from the NW is not necessarily a bad thing.

 

Just thought I'd mention the events of Dec 2000, as some seem to think any shortwaves from the NW will kill chance of cold weather, it all depends on the wider background state of things.

 

This isn't a forecast of what I expect see unfold, just sometimes useful looking how events have evolved in the past.

[Nick L]

Here are the +240 ECM clusters for the 12z (only have access to the Europe view)

 

[Biggin]

 eg Leeds has a 35% chance (snow chances are listed on the graph) of snow on one of the upcoming days:

 

graphe3_1000_267_2___.gif

 

 

But isnt that 9 days away ?? Wouldnt trust that with my missus

[bluearmy]

Maybe Ian Ferguson can comment on UKMO on metoceil

Données pour les cartes UKMO entre 6h et 72h partiellement revenues (Z500/T850 de 12h en 12h) mais instable !

Data for 12-72h UKMO charts partially back (Z500/T850 at 12h interval) but instable availability !

Written in red and has the loss of Low pressure system for NE US. Has data for this region been lost or satellite data not reading.

Pre 92z the data is only there for Eurasia.

The ukgm raw data isn't available for the areas not showing on the meteociel screen. No data loss. Just not available for public consumption.

Back to the here and now, ECM ens spread days 9/10 show the envelope spread to our west on the cold and low heights which may increase the risk re the initial cold headed to our west before it comes east behind a clearing depression. However, the spreads also show the mid Atlantic depression more likely to be further south as is heads east. Infact the control has a stream of features passing sw/ne just to our southeast. The ECM extended ens anomolys keen to drop the highest low anomoly to our south whilst the Atlantic ridge tries to edge in but remains decently centred just se of Greenland.

The means and anomolys really not a concern re likely wintry conditions countrywide post Xmas.

The control, interestingly build that ridge over he top of the sinking trough into Europe as the gfs did earlier today.

Nick L - love that cluster post but I fancy you might have a message in your inbox if anyone at ECM sees it!

Edited December 17, 2014 by bluearmy

[Frosty.]

Tonight's GEFS 12z mean shows a cold outlook from T+168 hours onwards with a persistent scandi trough and height rises to the NW with the azores high not intruding. The weather would be wintry with snow at times and frosty nights with an arctic sourced airmass, 2m temperatures struggling in the low single digits celsius range. There are some peachy looking 12z perturbations with strong arctic blasts and just a few rogue flatter options. I would say the models today have ticked lots of cold boxes and I expect even better in the build up to christmas, this is work in progress and it's looking good.  

[ItNeverSnowsInWindsor]

The ECM 12z isn't that great for S England with the high in Europe making things complicated and delaying the cold from filtering all the way down to the South. Eventually though the outcome is cold for the whole of UK but its delayed by a few days compared to the other models.

Edited December 17, 2014 by prolongedSnowLover

[Cheshire Freeze]

ECM day 10 ensemble mean is very, very good. Would prefer to see slightly stronger heights around Greenland but it's certainly not to be sniffed at.

I have a sneaky feeling that post N Atlantic ridging we may have to hope the high gets sheared enough into Scandi to allow height rises there in order to prolong the spell. Too far out to worry about now but it's something to take into consideration.

I think we may well need another cracking of the whip to get an established cold spell but overall I'm fairly satisfied with today's runs thus far. Don't expect too much and you won't be disappointed!

Edited December 17, 2014 by CreweCold

[Penrith Snow]

I can't believe it, the last time I looked at the models was Monday morning and they were grim. After being at a conference I come home and log on expecting to find a Christmas Bartlett!

I must give myself a break from model watching more often!

When did the models suddenly flip? On Monday morning they were trending towards very mild?

GFS tonight is remarkable.

Andy

[Mark Neal.]

fergieweather, on 17 Dec 2014 - 20:27, said:

EC EPS clusters rolling out currently. Will check them later.

Update from Ian F
Varied colder NW/northerly types by 28th onwards