Model Output Discussion - 21st - 28th November

[ukpaul]

ECM stalls the low that it and GFS have to our North around the 5th Dec, agreement between them before that for similar lows crossing on Mon/Tue and Wed/Thu next week. Will be interested to see if one comes into line with the other over the next few days.

[Frosty.]

R.I.P Gary Speed - ONE OF THE BEST MIDFIELD PLAYERS IN THE PREMIERSHIP

The models currently show a trend to colder weather over the course of the next 10 days but of course the end result could be a flatter zonal pattern with average temps... I have come in for a lot of negative response today but I was not misleading anyone, indeed i was only saying what the models are showing which I believe is the whole point of this model discussion thread!

Edited November 27, 2011 by Polar_ Low

[shedhead]

Good post Nick, but to my mind the thread has descended into those who are taking the current outputs on face value and those that are comparing them to recently and simply reading to much into them re prospects of cold.

However, what cannot be argued is the fact the thread has descended, so perhaps it's time to draw breath and let a little water pass under the bridge.

[Osbourne One-Nil]

This is the model discussion thread. Why do so many find that such a difficult concept to grasp?

[ukpaul]

The models need to be looked at rather than comparing to some memory of last year, compare the output now to previous years and you realise that there is no typical winter.

Looking at the current models without emotion and there is a clear pattern change, more for the north than the south but it is there. If you look ahead to next Saturday then you can see another disagreement between GFS/ECM and that's one to look for.

(I'd presumed that talking about models in general rather than specific output was acceptable, is that not the case?)

[Isolated Frost]

Very average fare- a mixture of mild sw winds (mainly tomorrow), cool polar maritime winds (uppers conductive to snow above 200m in scotland, 300m in n england, up to 500m in the south), southerly tracking lows (possibly very wet and quite average weather), and the odd toppler delivering snow to northern parts and coasts..

Nothing like blowtorch mild zonality, or massive cold spells, something inbetween, just simple zonality basically. Downstream there is little to shout of from a coldies pov, but there is enough energy in that jet to force lows southwards, and even inject a lot more polar energy than usual.

I sense southerners will be much more unhappy with the outlook as the temperature gradient from wick to west ham is rather high, as per usual in a atlantic-dominated flow.. cool and wet in the north, average and at times wet in the midlands, drier and milder in the south.

Calm down dearies! If this is the 'mild' month as net-weather, and the technical boffins round here are saying, then i'd be jumping with joy!

[Ruzzi]

What a stark contrast to current affairs? Never knew we were back in December 2010!

I make no apologies for this being off-topic because the negativity in here is disgusting sometimes. All I asked was a simple question and that chart of december 2010 was used to enlighten me however you jumped down my throat right away to point out that it was last year's chart! I knew fine well it was last year's chart!!!!!!! Maybe I'll just keep my mouth shut like many others do on this forum instead of trying to learn something from more experienced members, in the fear (like many others) that people will jump down our throats!

[reef]

You know, its interesting, usually when I read through here I have a scan of what posts are off topic or bickering and remove them as necessary, but today its more a case of which ones are worth keeping.

How about we discuss the models and not argue on a Sunday afternoon about small details that are a week or so out?

[kumquat]

Where's the objectivity gone?

[Osbourne One-Nil]

Just to add to Reef's post.....every time someone posts an off-topic post, or a one-liner, or tells someone else off, or states how off topic everyone's being, or includes the phrase "off topic, but..."...the team get numerous reported posts. These all need dealing with, and you know what, it's our weekend too.

The rules are dead easy to follow, it's not exactly difficult to self-moderate. If you wouldn't be interested in your post had someone else written it, then it's not worth posting. If it's not directly related to the models, then it's off topic.

[OldMetMan]

The last 2 GFS depict an interesting, and somewhat unusual pattern of development. Now that the Atlantic LPs seem to be pushing through unimpeded, even if pressure is still relatively high over the south, the development shown by those models would seem quite possible, at least in the short- to mid-term, with LP taking progressively more southerly tracks, extending the upper trough to the NE and E further and further S into Europe, and consequently bringing down thickness values over the UK.

The 06Z GFS end of run shows strong HP taking up position mid-Atlantic, a scenario I suggested might happen some days ago, and if the upper trough to the E does amplify as shown by the GFS, then that seems a distinct possibility. Thereafter, a more amplified upper pattern might allow LP to provide the UK with some northerly bursts - of course, that's a long way off.

Just something to remember, in a situation of LP tracking progressively more to the S, the cold air usually wins. This has often happened in the past. What is in doubt is whether this involves a setting up of a more static upper wave pattern, which, given the mobility and energy shown over the Atlantic right now, doesn't seem very likely to me - yet - so any cold would be short lived.

Having said that, last November switched very quickly from a mobile to static pattern in a very short time prior to the intense cold starting. I'm not suggesting a repeat of that I hasten to add, but, as I have said before, if such a situation is to evolve, watch for very cold air accumulation, and associated HP, to the N or NE. I shall watch subsequent GFS runs with interest to see if the development it shows is maintained.

[Liam J]

It seems we are back to a more typical type Winter for the UK at least for the early season anyway, hunting blink and you miss it northerly topplers in FI. I think we're miles away from any prolonged cold spell of weather with nothing to go on to suggest otherwise, cold and zonal seems like the order of things and this pattern may last a fair while.

The charts are looking like a normal synoptic set up from the Winters of the past, that is of course before we had the last two cold and snowy Decembers thrown at us.

Prolonged cold and snowy Winters are not the norm for the British Isles, last year even more so was an exception but some people seem to think it should be a regular occurrence.

So in the medium term I'm going to look forward to weather much more typical for the time of year as the model guidance is showing which will deliver stormy and wet spells with incursions of PM air temporarily digging down from the north as depressions develop and cross the UK from the Atlantic. high ground especially towards the north will see snowfall with the risk of lowland snow at times, but nothing long lasting or especially cold, as you were.

[January Snowstorm]

The cold bottled up over Greenland really is intense.

I can't help but think Northwesterly's will pack quite a punch this Winter!

[Frosty.]

Sounds like you're wanting cold and snow as much as me, but won't the models show more cold and snow in FI partly because we are heading more into winter? Excuse my ignorance if it doesn't work that way, proper novice here.

Not necessarily, the mild blocked pattern could have occured at any time but for it to last for so long this autumn was a surprise and a disappointment, at last the weather can now be how it should be at this time of year with a risk of cold snaps and a cooler zonal pattern with colder zonal at least for the north but hints of a nationwide cold snap in FI.

[BLAST FROM THE PAST]

General NW'ly flow ahead with some stormy conditions. Hill walking will become dangerous. I think a cool to chilly period is ahead of us according to the models and not mild.

Edited November 27, 2011 by Osbourne One-Nil
Edited to be within the topic of the thread.

[clark3r]

Not necessarily, the mild blocked pattern could have occured at any time but for it to last for so long this autumn was a surprise and a disappointment, at last the weather can now be how it should be at this time of year with a risk of cold snaps and a cooler zonal pattern with colder zonal at least for the north but hints of a nationwide cold snap in FI.

Not necessarily, the mild blocked pattern could have occured at any time but for it to last for so long this autumn was a surprise and a disappointment, at last the weather can now be how it should be at this time of year with a risk of cold snaps and a cooler zonal pattern with colder zonal at least for the north but hints of a nationwide cold snap in FI.

Where do you see the hints of a nationwide cold snap? I do see on the ECM that high is strenghing way to the north east of us!

[Stratocumulus perlucidus]

12z Rolling out.

That greenie squeeze looks familiar. :smilz38:

[Liam J]

GFS still picking up on the storm later this week, 12z more intense with the depression, sub 950hpa

Edited November 27, 2011 by Liam J

[Matty M]

12z GFS looking decent.

We are squeezing something out of a poor NH synoptic so i suppose it is a good sign.

Should be good bash at some sort of northerly towards the end of 192hr suite

Good chart for Scotland. A taste of winter coming in the next 10 days, a coold start to the week, small mild incursion, chlly and brisk west north westerly for Friday/ Saturday and the chance of a more substantial winter feed from Day 7.

[Matty M]

FI of GFS is garbage, so coldies i would advise not to look!

The shorter term stuff does however provide some interest, we have snow and gales for Scotland, a few frosts and perhaps wintry showers elsewhere.

Also the Alps would get a welcome pre Christmas snowfall.

[Frosty.]

Where do you see the hints of a nationwide cold snap? I do see on the ECM that high is strenghing way to the north east of us!

I based it on the Gfs 00z mostly, it showed an arctic blast in FI with the 528 dam line reaching southern england and a potent wintry blast for eastern and especially northeastern uk but cold air for all of the uk, the ecm 00z also shows a northerly flow in FI for all areas but the coldest weather in the north. The latest meto update is not enthusiastic about any widespread wintry weather and restricts any snow risk to upland areas of the north which is disappointing considering the main model operational runs this morning.

Edited November 27, 2011 by Polar_ Low

[wimblettben]

Another very windy spell in Northern areas?

Quite a while away yet though so will have to see whether the model tones down the low or removes it altogether.

[Frosty.]

I notice with interest that the Gfs 12z also shows an Arctic blast in early FI, it will hopefully mean that we have our first genuine cold feeling spell of the season although the general pattern will be nowhere near as good for sustained cold as last nov/dec when the atlantic became blocked and the jet looped up and over a mid atlantic high and then tracked across northern france.

[vortex_liam]

Another very windy spell in Northern areas?

Quite a while away yet though so will have to see whether the model tones down the low or removes it altogether.

They will probably downgrade severely...

Btw, IM BACK hopefully my few skills and 2 years of experiences will help.

Well this may be 2 weeks off and i doubt its accuracy but it looks worrying down south at +276. Hopefully will change in fact it will change, for the better or worse?

[damianslaw]

Models continue to paint a very unsettled scene for the foreseeable future - very traditional late nov/early dec fayre.. They also continue to suggest next weekend could see a more widespread polar blast of air for the whole country as we see the trough move sufficiently eastwards to pull down a cold northwesterly with building heights out to our west and northwest. I'm not suggesting any widespread significant cold, but the prospects of some lowland snow over scotland at least by this time next week do look quite high- and it will feel preety cold everywhere in the chilly winds... still no by means certain we will see colder uppers dig southeast but such synoptics are mearly within reliable timreframe..

Long term - in zonal set ups reliable timeframe is particularly short - lots of various outputs may occur, but I expect more of the same for some time yet..