Model Output Discussion - 19th - 25th December

[Frosty.]

Does it matter? Not particularly, just enjoy the day!

FYI, the real situation is that as yet there is no signal for impending cold weather, not a medium or long range signal (Strat warming aside), in general the cold is staying in the far reaches of the model output and the scenario is changing every day. There's nothing there.. I'd love to be able to say the opposite, it just isn't my thing to do that with little back up, that's all.

By the way I'm very miserable

For the record I agree with KW.

hey i'm glad we agree on that at least

[shedhead]

But the only long range we can see are the gefs and gfs op. From a NH perspective we now see higher heights getting into the arctic which we haven't seen yet this winter on the models. That is what the fi models ARE showing. It may verify, it may not. Surely it is ok to discuss it's possible ramifications in this thread.?? If you are only going to look at the European/Atlantic charts, you won't get a perspective on what's going on wit the 'big picture'.

I agree to a point BA, but I have to say the hemisperic models and even those for the N Atlantic only have shown height rises to the north earlier this month. On several occasions cold Nerlies were progged, only to vanish into the ether on subsequent runs. The difference this time tho is the strat is warming, but that in itself is no guarantee of cold for the UK and whether we get a full on SSW remains to be seen. No doubt prospects from mid Jan are better, but that is all that can be confidently said at this stage imo.

Edited December 25, 2011 by shedhead

[bluearmy]

The mid atlantic high is not going to be any use in generating a pattern change unless there are changes in the arctic and with the strength/positioning of the vortex.

I urge you all to be a bit less 'imby' in your assessment of current deep fi and take a look at the NH instead. Without hemispheric pattern changes, we don't have much hope of getting out of our current setup. (at least not into a colder one).

[IDO]

But the only long range we can see are the gefs and gfs op. From a NH perspective we now see higher heights getting into the arctic which we haven't seen yet this winter on the models. That is what the fi models ARE showing. It may verify, it may not. Surely it is ok to discuss it's possible ramifications in this thread.?? If you are only going to look at the European/Atlantic charts, you won't get a perspective on what's going on wit the 'big picture'.

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level. Out in FI there is a suggestion of another warming episode but that is then and we are now talking about the current output. There is likely to be no effect from warming in the next 3-4 weeks. So if there is a change due please be more specific as I am unable to see where from. It looks like cold zonal up north and cool zonal down south till the end of FI (Jan 10th). A glance at the last FI in GFS has the Jetstream above the Orkneys with no clear blocking patterns. Scanning the professional forecasters none of them are predicting any cold spell in January.

The plethora of statements saying real cold is on the cards needs some clarification.

"Cheese Rice" Thanks for posting the ensembles for Aberdeenshire, very helpful for about 0.5% of the population. The same graph, for the same period, has max temps, for London, between 2-7C; pretty much average to cool.

[bluearmy]

I agree to a point BA, but I have to say the hemisperic models and even those for the N Atlantic only have shown height rises to the north earlier this month. On several occasions cold Nerlies were progged, only to vanish into the ether on subsequent runs. The difference this time tho is the strat is warming, but that in itself is no guarantee of cold for the UK and whether we get a full on SSW remains to be seen. No doubt prospects from mid Jan are better, but that is all that can be confidently said at this stage imo.

That's where I possible diverge from some of the other opinions and more into Ian's territory. Transient northerlies, mid Atlantic highs, topplers into Greenland. Not much of a change from what we've already seen through December. We do see changes afoot in the arctic and if they verify, we will see cold into the mid latitiudes. Whether that means nw Europe ??????????

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level. Out in FI there is a suggestion of another warming episode but that is then and we are now talking about the current output. There is likely to be no effect from warming in the next 3-4 weeks. So if there is a change due please be more specific as I am unable to see where from. It looks like cold zonal up north and cool zonal down south till the end of FI (Jan 10th). A glance at the last FI in GFS has the Jetstream above the Orkneys with no clear blocking patterns. Scanning the professional forecasters none of them are predicting any cold spell in January.

The plethora of statements saying real cold is on the cards needs some clarification.

LOOK AT THE NH CHARTS GFS AND GEFS POST T300 !!!!!!!!!!!!!!!

"Cheese Rice" Thanks for posting the ensembles for Aberdeenshire, very helpful for about 0.5% of the population. The same graph, for the same period, has max temps, for London, between 2-7C; pretty much average to cool.

[SP1986]

I agree to a point BA, but I have to say the hemisperic models and even those for the N Atlantic only have shown height rises to the north earlier this month. On several occasions cold Nerlies were progged, only to vanish into the ether on subsequent runs. The difference this time tho is the strat is warming, but that in itself is no guarantee of cold for the UK and whether we get a full on SSW remains to be seen. No doubt prospects from mid Jan are better, but that is all that can be confidently said at this stage imo.

I also agree with this, I have been watching models for a long time (computerised models that is), and I've seen many stratospheric warming events come and go, and they don't always play ball, for what I now understand is due to positioning and atmospheric level filtering. However before I understood the basics of Stratospheric warming, merely putting faith in what other more knowledgeable members suggested, I realised the Stratospheric warming isn't always 100% proof - I'm sure people know that, I don't need to say that - however I have been in events where Stratospheric warming has impacted, although in the past these events have been fairly short lived.

The only thing we can really go on is the model outputs, we can't simply assume Stratospheric warming will have an impact without seeing the changes on the models first, because we simply won't know there will be a massive pattern change that favours cold until that happens.

My post this morning probably was a little OTT, although my humour doesn't really suit everyone, but the bottom line is, if the models aren't showing it yet, that's because it's not signalled yet - that's not to say it won't turn to cold, but that some of the remarks that the pattern is changing are not really justified by the overall model suite - and not justified by consistent, major agreement in the models overall - at least not yet..

[kold weather]

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level. Out in FI there is a suggestion of another warming episode but that is then and we are now talking about the current output. There is likely to be no effect from warming in the next 3-4 weeks.

True to an extent, but as others have said in the Strat thread, the models are STRONGLY hinting at a major warming event between the 10-20th of Jan. i'm not really well enough versed in that side of things to notice the signs but several of the 'experts' in that field certainly seem quite keen on a second warming event that will be the one that will do ther job. This first event was simply to set-up the scene.

As BA said just now, the models aren't really showing any hints of sustained cold spell yet, and I for one wouldn't expect them too just yet either, however if we do shift to a pattern with topplers like is suggested by BA, that would still be a LARGE change to what we had before, which was a cool pattern made that way by a stupidly strong +ve AO and a enlarged PV. Whether or not it ends up being cold is quite another matter. I do expect though that the models will for the medium term continue to show a rather unfabourable Atlantic pattern.

PS, my earlier comment wasn't aimed at anyone, it was more of a general comment that anyone who thinks there is NO change afoot at all are not looking at the bigger picture at all.

[Duane S.]

anyone who thinks there is NO change afoot at all are not looking at the bigger picture at all.

+1 to that. I posted a few days back to say no real signs were showing on the models, FI or otherwise. A few days on, IMO, this has now changed.

There are signs that changes are afoot and this ties in with the strat forecast. This will probably serve to deliver a serious blow to the dominace of the PV before a bigger warming finishes it off later on January. BUT we will have to endure some mild and mediocre weather before we get there, of that there is little doubt.

Edited December 25, 2011 by s4lancia

[Frosty.]

+1 to that. I posted a few days back to say no real signs were showing on the models, FI or otherwise. A few days on, IMO, this has now changed.

There are signs that changes are afoot and this ties in with the strat forecast. This will probably serve to deliver a serious blow to the dominace of the PV before a bigger warming finishes it off later on January. BUT we will have to endure some mild and mediocre weather before we get there, of that there is little doubt.

I absolutely agree that the weather has been very mediocre so far, or pants but there are some subtle positive signs going forward of a possibly colder pattern emerging?

[Optimus Prime]

Well still large agreement on very mild (record breaking in places) weather right the way through the next few weeks with little in the way of cold members appearing.. May it continue. It's good for the wildlife in general and makes everyone miserable - perfect.

[IDO]

The plethora of statements saying real cold is on the cards needs some clarification.

"LOOK AT THE NH CHARTS GFS AND GEFS POST T300 !!!!!!!!!!!!!!!"...bluearmy

I have had a look and cannot see any change to real cold; yes a lowering of temps from the mild at the moment but nothing that is statistically relevant for nearly mid Jan. GFS & GEFS all have average to cool for Birmingham & London. Even the CFS ensembles have the mean temps around average till Jan 19th; slightly colder from around the 12th for Scotland (& the North?). From the 19th I suspect that colder weather will move down further south, but it is likely to be settled cold rather than anything wintry. From very late Jan we will need the stratospheric warming to have dug into the models otherwise the continuation of a very average winter?

[Frosty.]

It's good for the wildlife in general and makes everyone miserable - perfect.

The wildlife adapts to whatever transpires, I think you are in need of a visit from the ghosts of christmas past, present and future tonight as you appear to be in a very negative mindset today.

Edited December 25, 2011 by Polar_ Low

[Cloud 10]

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level.

Has it?

[Optimus Prime]

The wildlife adapts to whatever transpires, I think you are in need of a visit from the ghosts of christmas past, present and future tonight as you appear to be in a very negative mindset today.

Lol. I had a visit from Christmas past. I liked what I saw, take me back to 1850 please.

I was joking. Merry Christmas everyone. Lets hope January 1987 past comes to visit us very soon.

[andy_leics22]

Stratosphere warming.. My ar*e

It's Christmas day for goodness sake, I love snow as much as the next man but I couldn't care less what the models are showing at the minute. If we have a mild January and the models are still showing mild mush for February then I will be annoyed but right now it really doesn't matter.

Edited December 25, 2011 by andy_leics22

[Frosty.]

Lol. I had a visit from Christmas past. I liked what I saw, take me back to 1850 please.

I was joking. Merry Christmas everyone. Lets hope January 1987 past comes to visit us very soon.

but not feb 1987..and definately not jan/feb 1988 Edited December 25, 2011 by Polar_ Low

[feb1991blizzard]

but not feb 1987..and definately not jan/feb 1988

I did get one good dumping in Jan 88, i think it was around the 10th - 13th, 6 inches from a Northerly but generally it was pants and that may have been a localised midland event i cant remember.

W.e could do with squeezing a bit more amplification and getting that high next week a weeny bit further North so we could get snow showers further south

[Frosty.]

I did get one good dumping in Jan 88, i think it was around the 10th - 13th, 6 inches from a Northerly but generally it was pants and that may have been a localised midland event i cant remember.

W.e could do with squeezing a bit more amplification and getting that high next week a weeny bit further North so we could get snow showers further south

I kept a weather diary and some of the winters in the late 80's gave me nightmares, apart from jan 1987..sorry mods off topic but its christmas day.. the models today are at least hinting at a possible pattern change but lots of mild dross to get through first.

[feb1991blizzard]

I kept a weather diary and some of the winters in the late 80's gave me nightmares, apart from jan 1987..sorry mods off topic but its christmas day.. the models today are at least hinting at a possible pattern change but lots of mild dross to get through first.

from about 88 - 93, with one obvious exception they were pretty dyer but i still think that had i lived up here then i would have not been quite as disappointed but the last few, low ground in the south east as done at least as well as here and probably better overall, typical, anyway last post on this as i dont want to incur mods rath,

[bluearmy]

I am obviously not explaining myself very well today. The models are not showing anything relating to deep cold in our part of the NH within a fortnight. However, there are plenty of indicators (fi model runs looked at in NH format) that events in the arctic will lead to something that will deliver deep cold to the mid latitudes in the week or so following. Of course, for as many areas receive deep cold, there will be others that stay average or are even mild.

[Frosty.]

from about 88 - 93, with one obvious exception they were pretty dyer but i still think that had i lived up here then i would have not been quite as disappointed but the last few, low ground in the south east as done at least as well as here and probably better overall, typical, anyway last post on this as i dont want to incur mods rath,

I'm just hoping that jan/feb are better than the dross we had this year but the strat thread is at least promising for something wintry in the next 8 weeks..anything will be better than the current muck.

[feb1991blizzard]

I am obviously not explaining myself very well today. The models are not showing anything relating to deep cold in our part of the NH within a fortnight. However, there are plenty of indicators (fi model runs looked at in NH format) that events in the arctic will lead to something that will deliver deep cold to the mid latitudes in the week or so following. Of course, for as many areas receive deep cold, there will be others that stay average or are even mild.

Sorry for sounding a little IMBY with regards to heights to west of us, to be honest it doesnt float my boat really but just something while we wait for strat to improve, you are explaining yourself but people are not listening, for what its worth i think deep cold unlikely until at least mid jan but if we have all the buliding blocks in place by then, i will settle for that, i dont rate the 12z though from a NH perspective, slightly higher heights towards GL but yesterdays runs were better, the 18z showing light blue over the pole and hardly any sub 500dam heights.

[IDO]

i'm dreaming of..., on 25 December 2011 - 13:30 , said:

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level.

Has it?

Not by the 3rd Jan but it is on its way down. The forecast for 30th December is T (90N-60N) = 11.52 and compare this to the 3rd Jan = 6.04 (at 1hPa).

Edited December 25, 2011 by i'm dreaming of...

[reef]

Its a good job I didnt come into this thread looking for information on what the models are showing, I would have been extremely disappointed if that was the case.

On a more serious note, I know its Christmas Day, but this thread has barely been on topic all day. Some people will have plans tomorrow and will want to know what the weather is going to do, so can we keep to the topic at hand?

Thanks

[Frosty.]

Its a good job I didnt come into this thread looking for information on what the models are showing, I would have been extremely disappointed if that was the case.

That's because the models are mild, mild and more mild.