Winter Model Discussion 06Z 10/01/13>

[The Northern Ramper]

Basically this is classic Gfs.

It picks up the cold signal first then slowly the others agree, the ECM at just 120 which leads to an Ian Brown wtf moment.

Then when all onside it develops shortwave drama in the mid term and goes off on one. Steadfastly refusing cold and blasting the Atlantic through the Uk.

Only for it to slowly over a day coming back in to line like a naughty schoolboy.

I have to say though that to do it within t96 is taking a liberty and we don't need to see that again any time soon.

[The watcher]

Please kepp on topic as the mods have been stating all evening! Moaning and general chat threads exist to discuss your grievances re. garden centre managment! Thank you!

Hi Sandra, best leaving it to moderators of the forum to say that. Just causes more clutter.

Welcome to the forums though, and don't worry about Ireland, -4 to -6 850's can be low enough for snowfall. Bring yourself on over to the Ireland regional forums for a more IMBY analysis on what the models show. It's in regional discussion area.

[UV-RAY]

I'm speechless really, I haven't seen charts like these since 1978/79, I know it's all if's and buts at this moment but there is a real prospect that many Western areas could see some very large accumulations of snow. It just seems like we will have one undercutting low after another, with widespread disruptive snowfall and some very low minimums with daytime temps not really getting above freezing for most of England and Wales.

[The Northern Ramper]

Well i for one am hoping for a slight adjutment west of the models which usually happens with gfs.(hopefully) again as it would mean more snow for us on the west coast. Do u guys think that it may move slightly west?

Yes

The models tend to underestimate cold from the east and there is often a westward shift of the uppers.

[Panayiotis]

Nice ensembles there for the 18z, compared to the earlier ones (12z) we had quite a lot of mild members for around the 15th but now most of them have sunk like a stone and only a few remain, looking at the ensembles this cold spell will start on the 12th and end on the 19th (return to average temps after) thats a 7 day cold spell which is good for me,and it could well upgrade.

[AGAL]

Please kepp on topic as the mods have been stating all evening! Moaning and general chat threads exist to discuss your grievances re. garden centre managment! Thank you!

Come on Sandra a little tolerance on such an evening as for me I'm a model of virtue so always on topic. Last one mods I'm off . Goodnight all after yet another exhausting but looking increasingly, a rewarding day.

Edited January 10, 2013 by AGAL

[Stoxs]

Come on Sandra a little tolerance on such an evening as for me I'm a model of virtue so always on topic. Last one mods I'm off . Goodnight all after yet another exhausting but looking increasingly, a rewarding day.

YES as it was all started to go off topic by a FORUM TEAM member, with an inaccurate quote.

Anyway appologies all sorry for a few extra posts to delete including this one .

P.s nice 18z lol

[kumquat]

Hi alan776600

We probably haven't got to the bottom of this yet, so yes further upgrades are very possible. Here's something I mused / updated in the seasonal thread 21/12/12 Mayan end of the world day

Now the bit in bold is the main point here, I am actually now concerned about the potential here. I have used the word 'deluge' in other posts, we are looking at serious amounts of snowfall with set ups like these ansd at the surface its gonna be mighty cold. Date record cold temp challenges? I've touted this and with deep snowfields, cold uppers, slack winds...possible. Its all possible as we look at it right now.

The GFS as continued to move away from its zonal 'mess'......long may it continue, and I suspect it will.

Solar / lunar technique says yes. The MJO, Strat, GWO , AAM, GP [we are yet to get to the core of his cold outlook but build up looks on line], C, ECM, UKMO, GFS, GEM etc say yes...for now.

BFTP

Good call...While we're blowing our own forecasting trumpets:

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Posted 26 December 2012 - 01:00

"there's just as much chance it could stall over the UK for a prolonged period before dropping back to the Azores"

The models are showing transient lows and any ridging doesn't look like hanging around for long in the nearer timeframe. I'm not sure any "stalling" is going to happen any time soon.

Having said all that, towards the far end of the outputs we are starting to see more amplification of the pattern. The propensity for short pulse lows fired across the Atlantic alternating with higher amplitude peaks (ridges) is definitely gaining momentum and as we pass T +240, there appears to be an offset (or delay) for the ridges to start to dominate as we enter the further reaches of the output. Artifacts like the Scandi highs being flirted with in FI by the GFS in the past few runs, Immediately blown away,of course, by the default set low resolution atlantic train as ever on the gfs runs. However, I think the time is coming when one of the high amplitude incursions will stick..and set. (especially if the vortex energy starts to disrupt as theorised) I'm betting on a Scandi ridge delivering an easterly by 12 Jan. Won't be bitter at that stage but a retrogression to Greenland will bring on a v cold second half to winter.

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[fergieweather]

In the east its also quite a dry run as far as I can see. Fergie has already been on tonight and said that the METO are not expecting deep driving snow in the next few days.

Not so: was referring solely to Saturday.

We have reason for concern Monday, then again Tuesday, and later in week too. UKMO closely on case for potential significant snow events in various parts of country based on combined GM, EC & MOGREPS output.

[BLAST FROM THE PAST]

Good call...While we're blowing our own forecasting trumpets:

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Posted 26 December 2012 - 01:00

"there's just as much chance it could stall over the UK for a prolonged period before dropping back to the Azores"

The models are showing transient lows and any ridging doesn't look like hanging around for long in the nearer timeframe. I'm not sure any "stalling" is going to happen any time soon.

Having said all that, towards the far end of the outputs we are starting to see more amplification of the pattern. The propensity for short pulse lows fired across the Atlantic alternating with higher amplitude peaks (ridges) is definitely gaining momentum and as we pass T +240, there appears to be an offset (or delay) for the ridges to start to dominate as we enter the further reaches of the output. Artifacts like the Scandi highs being flirted with in FI by the GFS in the past few runs, Immediately blown away,of course, by the default set low resolution atlantic train as ever on the gfs runs. However, I think the time is coming when one of the high amplitude incursions will stick..and set. (especially if the vortex energy starts to disrupt as theorised) I'm betting on a Scandi ridge delivering an easterly by 12 Jan. Won't be bitter at that stage but a retrogression to Greenland will bring on a v cold second half to winter.

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Excellent summary and welll done, of course I won't make any comment towards you, not worth stooping down low is it. Well done, look forward to your next medium, ranger. Worth having another crack if that is what you can produce.

BFTP

Edited January 11, 2013 by BLAST FROM THE PAST

[Paul Sherman]

Agree here with Ian.

They simply cannot expect to pick up on Microscale events until sometimes T12 - Look at the 2009 Thames Snow Streamer event, yes we got a Red Warning for that, but it was only picked up within 1 day, from the looks of some of the Faxes anything could happen if the winds become favourable over the next 5-7 days, Streamers or troughs for example, they simply are not going to be picked up upon until much closer to the events and there probably will be events in the east closer to the North Sea!

[Paul T]

Wow. what an awesome GFS in the context of the last day or two, eh?!

So, apart from the obvious what shall I say?

Well, lets start with the huge turnaround of the 18z, which was already shifting from the 12z and 06z.

Exibit A)

Next Wed 3am at 12z:

Next Wed 3am at 18z:

A biblical difference in temperature and set-up. Mr.GFS you should be ashamed. Big time!

Ok, so the ECM and GFS tonight:

The GFS is coming onboard and the ECM is the king; but why are they still different and what is the driver to a cold/mild or very cold spell?

Lets focus on 120hrs....a reasonable time frame for any model.

See below, Exibit B (GFS on left, ECM on right)

What we have here is the GFS still delivering great energy into the UK allbeit boosted by an azores/bartlett wannabe high. Whilst the ECM depresses the high south a further 500 miles and allows the jet/power to shift below the UK. In my view this is the key driver to the cold cycle prevailing.

I actually think the GFS can backtrack further from the downgrades on the 12z and 18z...

This could be one of those were its gets better and better as the actual weather approaches!

Edited January 11, 2013 by Paul T

[Dean E]

Not so: was referring solely to Saturday.

We have reason for concern Monday, then again Tuesday, and later in week too. UKMO closely on case for potential significant snow events in various parts of country based on combined GM, EC & MOGREPS output.

Completely agree with you there, Ian. Most of the heaviest and more memorable snow events (December 2010, January 2009 comes to mine) were only picked up a day or two before they happened. I remember January 2009 event being around 8-12 hours before the event due to a developing channel Low...

The key area is to get the cold synoptics in place first, before thinking about snow!

SM

Edited January 11, 2013 by SnowMania

[Supertee]

Why are the moderators not doing what they are supposed to be doing? Just been reading about farming and garden centres going bust. Maybe its just turned into a self-moderating, talk about whatever. The more senior moderators seem just as idle with threats to ban or delete people/posts.

[SE Blizzards]

Ensemble 2 metre temps. The mean not rising above 2c / 3c from Sunday onwards...

[peterf]

Why are the moderators not doing what they are supposed to be doing? Just been reading about farming and garden centres going bust. Maybe its just turned into a self-moderating, talk about whatever. The more senior moderators seem just as idle with threats to ban or delete people/posts.

it was a moment,and if you hadn't brought the topic back up.it would have faded into the breeze.

no harm done during a quiet spell.

[Geordiesnow]

I think the ECM run is still the best for potential although it seems it can over-do any easterly flow as it appears to have done so for this weekend. UKMO did not look too bad upto 120 hours but its 144 hour chart could go either way really.

Still waiting for those charts that have a clean easterly set up though, theres no real sign for very strong heights to our North but it could be one of those cold patterns which persists for a while with variable wind directions so everyone is in the frame, perhaps a little Dec 81 like.

[weather eater]

Well that was an eye opener, the 18z GFS this evening is like your friend you invited to a party a few days ago, but who kept saying he couldn’t make it, was not sure he wanted to go, had to go see his mother. Come the day of the party, he comes along rather reluctantly has a few drinks and before you know it he’s gone mad, running around picking fights, pinching all the girls bottoms, trying to kiss the male guests, breaking the furniture and threatening to throw himself out of the window, a bonkers 18z run. On a more serious note, it’s great to see a climb down by the GFS, but the crucial bit hasn’t finished evolving yet and it’s still only a narrow step between success and failure. I shall be happier if tomorrows runs still back the cold evolution, and I hope it’s still clink clink cheers in the morning and not plink plink fizz.

[Geordiesnow]

Haway GS,does nothing lift your mood,we are looking at some decent winter fare up here.what more could a Northerner ask for?

To be fair, the charts have got potential especially the ECM run but it can over-do easterlies I have noticed.

We just have to wait and see Peter because the GFS especially and perhaps the UKMO 12Z run has hinted at trying to nose the Atlantic in somewhat although upstream we have seen the GFS backing away from that to some extent.

[karlos1983]

Hi all, I've been away from the models all day, for the first day in oner a week, can someone give me a summery of what's occurred, but please give a genuine overview, I've missed many of the days outputs, which I'm gutted about, but I'm no troll, so relying on my good Netweather friends to fill me in. Hope that's ok mods, if not, do delete.

[The Enforcer]

BBC online graphics very inconsistent with the latest shorter range modelling and even their own TV forecasts/yellow warnings for Saturday in that precipitation in Southern England in late afternoon/early evening could be best described as 'minimal' for rain let alone snow. Here's one I made earlier.

Edited January 11, 2013 by The Enforcer

[Met4Cast]

Hi all, I've been away from the models all day, for the first day in oner a week, can someone give me a summery of what's occurred, but please give a genuine overview, I've missed many of the days outputs, which I'm gutted about, but I'm no troll, so relying on my good Netweather friends to fill me in. Hope that's ok mods, if not, do delete.

ECM tightened the cold grip, GFS 06z and 12z trended slightly towards the ECM, 18z trended more or less completely towards it with GFS ensemble members dropping like a stone too.

Cold persisting through until at least the end of next week with possibilities of significant snow events for just about anywhere

[karlos1983]

ECM tightened the cold grip, GFS 06z and 12z trended slightly towards the ECM, 18z trended more or less completely towards it with GFS ensemble members dropping like a stone too.

Cold persisting through until at least the end of next week with possibilities of significant snow events for just about anywhere

Thank's Daniel, I'll take your imput all day, seen you on here a lot, really appreciate that, so peeved, yet very happy I missed the models today, really needed a rest, think ill make the 00z tonight, here's to a good cold snap, and hopefully a prolonged one.

[Paul T]

BBC online graphics very inconsistent with the latest shorter range modelling and even their own forecasts for that period in that precipitation in Southern England for Saturday could be best described as 'minimal', for rain let alone snow. Here's one I made earlier.

forget the BBC online weather, i have never even been on the website, because i visit netweather et al!

Anyhow, nice little diagram - although to save yourself the effort i would just consult the NAE. Its the most accurate (and free!) short term model that is on offer for us plebs, and is bang on the money usually:

Below is the accurate version of 6pm Sat....

http://expert-images.weatheronline.co.uk/daten/proficharts/en/nae/2013/01/10/basis18/ukuk/prty/13011218_1018.gif

enjoy.

[Timmytour]

Back from the pub and catching up with things. What a mood in here with the GFS "coming on board"

Of course while we've been debating which was right GFS or ECM, its worth noting that they could both yet be wrong!!!. And the last time we got agreement the GFS went straight off it. will the ECM do the same?

it's quite strange to see the "pub run" hailed as GFS behaving itself at last. I've seen cold runs in the past (though not sure on this scale) which were swamped in caution due to it being the "pub run".

But I don't want to be negative nor do I have any negative feeling. Even in the deep dark dross of modelling back in December, I could see charts that were similar to ones in 1947 before that winter arrived and i want this year to be a new 1947!

A word about streamers.....and good to see Paul Sherman posting above. My memories of 2009 were of a met office warning for upto six inches of snow to begin falling from monday afternoon. Well I'd been reading Paul's posts in here about a possible streamer, and that duly arrived on sunday evening. We had seven inches of snow BEFORE the advertised 7 inches of frontal snow promised by the Met office was due to arrive. There was very little said by the Met office, to my memory, about the streamer snow. And when the so-called big event arrived, which I imagined was going to be fantastic on top of what we already had (in Broxbourne Herts by the way) it turned out to be a mixture of wet snow, sleet and even rain which did nothing at all to top up the totals we already had.

so...if we get a significant easterly wind...it's possible that areas 20 miles or so either side of the Thames might end up with significant snow that is not widely forecast hours, let alone days, before the event. That's what a streamer is!

Already, without any verification, this has been a fantastic couple of weeks of model watching. sometimes i think it's almost more exciting to see a model deliver a run of cold and snow, then it is to see it actually get cold and snow!

If the latest runs come anywhere near verifying, this will be a winter that i remember for the GFS picking up first, The ECM coming aboard and sticking with, the GFS dropping and only coming back online very late with, and the CMA taking an absolute age to come out!