Winter Model Discussion 18Z 8/1/13. The hunt for cold (is closer).

[Neilsouth]

A mega stunning Ecm 00z for cold, from as early as saturday and then continuing to intensify throughout next week with snow and severe frosts for all parts of the uk, comparing the ecm 00z today with yesterday's 00z shows a massive upgrade for cold, some parts of the uk could be looking at large snowfalls next week and beyond..snowbound uk has a nice ring to it.

If ever there was an example of a perfect sustained Northerly, the Ecm 00z shows it, synoptically superb

Not sure why you are clapping and getting excited at such a long distance? Seriously people anything beyond 46hrs is FI in this current set up, we've even had mistakes made on a day to day basis.

I'll say it again from previous posts, the models are are absolultly rubbish at medium term ranges! Trends doesn't work either

[abruzzi spur]

Lets face it, when do we ever harve complete cross model agreement aftershave

I'd buy a bottle of that!

[Gibby]

Good morning. Here is the latest report of the 00z output from GFS, UKMO, GEM and ECM for today Wednesday January 9th 2013.

All models show a cooling trend over the remainder of the week and weekend. Most areas will see a bright day with some sunny spells after frost and fog clears from the North. The front from yesterdays rain is just to the South of the UK keeping things rather cloudier here. On Thursday a front approaches the SW with some rain while other areas see drier and brighter conditions though there could be some showers in the East. Friday sees a dry and bright day away from the East Coast while on Saturday a Low pressure is shown to move SE over the Western side of Britain and on down into France later in the weekend. Rain will move across West and SW Britain with some sleet or snow over the hills possible before an Easterly wind sets in for Sunday with some wintry showers of sleet or snow in the East. It will become cold everywhere by then.

GFS then shows a ridge moving across the UK from the West replacing the Northerly flow with an Anticyclonic flow, especially over the South with frost and fog by night. North-Western regions become milder under a SW flow with some rain at times. Through FI this morning High pressure is shown close to Southern Britain with a lot of fine weather here with frosty nights while many areas see more cloud at times with occasional rain running across from the West with colder and brighter spells in between. Temperatures through this period will be just below normal although rather milder in the NW for a while.

The GFS Ensembles show a rather cold spell to come with the operational on the mild side of the pack in the second half of it's run. There are many very chilly runs with the Control Run taking us into the freezer with time although it takes us back into the very mild category later next week.

The Jet Stream shows a Northern arm ridging high up to the North of the UK while a Southern arm is shown moving East to the South of Britain for a time before returning North to the UK later.

UKMO for midnight on Tuesday shows Low pressure over NE England with a chilly NW flow over the UK with rain at times, falling as snow in places over more Northern and Eastern areas.

GEM shows a much colder scenario at that time with Low pressure further South over Northern France with some snowfall for many under a cold Easterly wind, a pattern maintained for some time as new Low pressure keeps winds in the East with further snow later in the week. Winds back Northerly by the end of the run with a cold Northerly flow and snow showers down all Eastern coastal counties while the West sees dry and frosty conditions.

ECM shows a very similar sequence to GEM with Low pressure to the South keeping a snow risk for many Southern areas at times before winds back towards the North with even coder weather likely for many by the end of the run with heavy snow showers to many Northern and Eastern areas.

In Summary this morning we have a typical complex set of runs which are struggling to handle synoptics that could bring a significant cold and potentially snowy spell over the UK. GEM and ECM both show a very wintry back half to their run while GFS has done a reversal in its operational keeping high heights close to the South while UKMO after a cold and wintry weekend shows at least a temporary incursion of milder air towards Southern and Western areas. Further swings are likely over the coming days and though the temptation of excitement over mouth-watering charts for snow lovers remain I would caution to keep feet well and truly on the ground as things may still not turn out as some models currently show, mild or cold.

[lord stratus]

What I would remind everyone is the words of Ian F sometime ago where he reminded us that the MET rarely look at the gfs especially after day 8, preferring instead the UKMO, ECM, MOGREPS and jma...

I assume we all hang off every nuance of the gfs runs as they come out 4 times a day and it is all freely available...

You make me laugh. When the gfs shows great charts its the leader of the pack. It's the poorest of the big three today though!

Lets hope the charts firm up on this most micro managed cold spell in history, to avoid further toy throwing & tantrums!

[TAFKAP]

Great charts but you can bet had it been a mild outcome the shannon whatever wouldnt be mentioned. Whenever cold and snow is in the mix in the UK bottoms start quivering .im hoping it is a very severe spell of weather just to test the airheads who think 7 degrees is bitterly cold. Big respect to Fergie for the snippets of info. But given the seriousness of what could happen i bet his bosses have told him to give very minimal info.

Good point you have their, apart from the elderly, ill and very young who do need protection from cold I am always highly amused to go to work on a mild morning with no wind chill like today and see people dressed like they are about to embark on an arctic expedition. I see people in huge scarves, thick gloves, fur Ushankas etc. What do they do when it is actually cold? These are the same ones who come into the office on a lovely frosty, bright morning and moan about how cold it is and they can't stand it.

NB The coldest I have been personally is -30 degrees C. Now at at that temperature you can complain, not at 5 degrees above freezing!

[Great Plum]

You make me laugh. When the gfs shows great charts its the leader of the pack. It's the poorest of the big three today though!

Lets hope the charts firm up on this most micro managed cold spell in history, to avoid further toy throwing & tantrums!

I have been attempting to be level headed re this upcoming spell and hopefully my posts reflect that... I'm not saying to discard the gfs when it shows poor - and of course ill comment on it - it's got the most info - I'm just trying to temper people's mood swings!

[Southender]

The majority of the EC ens appear to lean towards the atlantic breaking through by mid-late next week. I suspect that will change again though!

[Polar Maritime]

Not sure why you are clapping and getting excited at such a long distance? Seriously people anything beyond 46hrs is FI in this current set up, we've even had mistakes made on a day to day basis.

I'll say it again from previous posts, the models are are absolultly rubbish at medium term ranges! Trends doesn't work either

The chart frosty posted was an example of a perfect chart for a Northerly, im shure he is fully aware that it wont happen at that range..

And trends are what we are always looking for in the models.

Edited January 9, 2013 by Polar Maritime

[Weathizard]

According to Matt Hugo the EC ens back the Atlantic breaking through by 168 on majority but I think the OP, control and high res backing against that is quite significant, higher resolution is critical in setups like this.

[Hammer]

The ECM ens seem to change every 12 hours as if they are facing some sort of computer personality disorder. I am not suggesting we dismiss them, but they are of little use if they are not showing any consistency.

[NickR]

-14!!! That would be insane...You would literally have to cover outside pipes ups ETC they would burst 0.0

Yes, we haven't seen temps like that for... all of 2 years. LOL

[Ali1977]

GFS has been quite consistent about snow on sat on its precip charts, why are no websites/ news showing this?

[Neilsouth]

According to Matt Hugo the EC ens back the Atlantic breaking through by 168 on majority but I think the OP, control and high res backing against that is quite significant, higher resolution is critical in setups like this.

The issue with Matt Hugo is, he is as unreliable as a long range GFS model! He himself uses models and then gives us a forecast based on those models.

I think we should have two threads on this forum, one for close range ( upto 46hrs ) and the second thread, anything behond that FI

[bradymk]

According to Matt Hugo the EC ens back the Atlantic breaking through by 168 on majority but I think the OP, control and high res backing against that is quite significant, higher resolution is critical in setups like this.

Yes not so good news from Matt and I am sure the high res is the actual op model. I would not worry too much however due to the constant changing in the ECM ens and in all models infact but caution required, cold definately not a done deal yet. Edited January 9, 2013 by bradythemole

[No Balls Like Snow Balls]

The issue with Matt Hugo is, he is as unreliable as a long range GFS model! He himself uses models and then gives us a forecast based on those models.

I think we should have two threads on this forum, one for close range ( upto 46hrs ) and the second thread, anything behond that FI

He is just saying what the ensembles are showing. Is that un-reliable in your head LOL. Isn't it the ensembles that are un-reliable rather than the human????

Edited January 9, 2013 by No balls like Snow Balls

[Radiating Dendrite]

Yes, we haven't seen temps like that for... all of 2 years. LOL

One year actually.

Was down to -15c in feb last year.

What can I say about the models - well the ECM is still great, but it has lost its number one reliability status for me with its performance over the last few months.

GFS is messy in the mid term, it has started chucking shortwaves in. This is normal though and should not cause concern, the charts yesterday looked like they had been drawn by a snow god, they were not going to continue.

The 6z may pose more questions I feel!

Edited January 9, 2013 by Radiating Dendrite

[fergieweather]

AFAIK, the netweather forecasts are based on the latest GFS run, whilst the MO, whilst computer generated, take in a gauge of all the NWP. I wouldn't worry about precip values yet, especially when Saturday is just the start.

edit: JH beat me to it

No: the UKMO and BBC web icons are both driven solely by raw UKMO-GM GRIB data and no other NWP. MeteoGroup - which many of us like - is driven by ECMWF and thus quite a rarity.

[john mac]

I've been impressed by the lack of mood swing in here this morning, as Ian f said the uncertainty is at record high levels with the models throwing out many different outcomes. Still more to come I think.

[Dave Kightley]

The issue with Matt Hugo is, he is as unreliable as a long range GFS model! He himself uses models and then gives us a forecast based on those models.

I think we should have two threads on this forum, one for close range ( upto 46hrs ) and the second thread, anything behond that FI

I think if anyone could make a forecast for next week it will most proberly be wrong by 6pm tonight

[Neilsouth]

He is just saying what the ensembles are showing. Is that un-reliable in your head LOL. Isn't it the ensembles that are un-reliable rather than the human????

Oh the oh so reliable Ensembles!

I think if anyone could make a forecast for next week it will most proberly be wrong by 6pm tonight

True!

[weather eater]

Not sure why you are clapping and getting excited at such a long distance? Seriously people anything beyond 46hrs is FI in this current set up, we've even had mistakes made on a day to day basis.

I'll say it again from previous posts, the models are are absolultly rubbish at medium term ranges! Trends doesn't work either

I have a certain amount of empathy with your post while not agreeing completely, I do think it possible to spot trends but not always, frequently in any sequence of runs more than one trend may manifest itself, however trying to pick the correct one is pretty hard work and beyond most of us and its pretty difficult for those with really good metrological knowledge. Mostly I feel you can trust the models a bit further out than you suggest, I’d say 72hrs.

Then 72hrs -120hrs 70% broadly correct but the smaller details will change, often crucial ones for us,

120hrs – 168hrs 30%, much broader changes likely, often drastic ones,

Everything after is not really worth bothering with.

Edited January 9, 2013 by weather eater

[A.J]

Just a reminder that this is the Model Output Discussion thread......Quite a few off topic posts creeping in....think before posting...ta!

[bradymk]

well the op and control are identical at 168 on the EPS postage stamps. http://www.knmi.nl/e...agse/index.html these extended ecm ensembles show that well as the op and control follow the exact same pattern basically and just look at how cold the control goes once the op forecast period runs out. Let's hope the op and control have a good idea on this im sure it will change again though. Looking at these ensembles, they are pretty good for cold however these are for de bilt so may be a lot different to London ones.

Edited January 9, 2013 by bradythemole

[Lynxus]

Well, The Ensemble for here ( and most of the UK ) is now showing a shorter lived cold snap

This to me is still good confirmation that yes, there is cold on the way.. For how long though?? Anyones guess. The west could barge right in our it couldn't.

I think the main thing to take away from this is that from today the uppers will start to drop. So this is good.

Even looking right up to FI , Yes currently it does show some warming again and becoming less cold however it still seems to keep with the colder theme and cooler air is never too far from us.

Today is certainly going to be interesting watching the models.

[karlos1983]

GFS has been quite consistent about snow on sat on its precip charts, why are no websites/ news showing this?

I think given the uncertainty it could well come down to now casting, or certainly a case of more runs needed.