Winter Model Discussion - Cold Hunting 08/01/13 00z Onwards

[nick sussex]

Looking at the clusters one could understand why if you were having to make a judgement call, you would have to go with the Op.

Too much variance I suspect to put any emphasis on any probability.

The ECM this morning is a little better than last nights which wouldn't be difficult.

Interestingly theres been no further overnight movement by the rest of the ensemble suite to the op,there is a way we could still get something out of the ECM trend if the pattern is edged further west.

[Methuselah]

Indeed, but we still need the NAO on our side Fred and I believe we will see this turn negative later in the month.

And that'll only happen as-and-when the required synoptic pattern establishes itself...The NAO and AO are derived numerical indices...

[Neiller22]

Says it all that meto possibly going for milder outcome if I'm reading fergie's quote correctly!! Not easy to forecast it would appear.

[UV-RAY]

And that'll only happen as-and-when the required synoptic pattern establishes itself...The NAO and AO are derived numerical indices...

Well Do'h I didn't know that RP.

Indeed, this is why when the effects of the SSW do kick in we will see a quick response in the NAO.

[bradymk]

Says it all that meto possibly going for milder outcome if I'm reading fergie's quote correctly!! Not easy to forecast it would appear.

Reading it correctly shows that UKMO guidance for 00z isnt until 11 o clock so noone knows what will be said yet.

[Methuselah]

So the GFS handling Greenland better is out of the window now Ian is it because its not showing the mild outlook you seek? You are the one that quoted this when GFS was showing low heights over Greenland....on that basis I would suggest you are not being objective but seeking any outlook that suggests this and going with it.BFTP

That may be so, Fred. But don't we see similarly-'flawed' arguments from those wishing to see a 15-day whiteout? Perhaps we should all try and keep to the 'facts'?

[fergieweather]

Says it all that meto possibly going for milder outcome if I'm reading fergie's quote correctly!! Not easy to forecast it would appear.

As it stands they suggest weekend cold block short lived; then temporary milder phase; then cold again. That was based on 12z analysis. I can't pre-judge what they'll issue based on 00z.

[UV-RAY]

As it stands they suggest weekend cold block short lived; then temporary milder phase; then cold again. That was based on 12z analysis. I can't pre-judge what they'll issue based on 00z.

I would agree with that from what I've seen from the model output and one which I mentioned a day or two ago.

[Snowman31]

CMA model looking promising at 168 :-)

[BLAST FROM THE PAST]

That may be so, Fred. But don't we see similarly-'flawed' arguments from those wishing to see a 15-day whiteout? Perhaps we should all try and keep to the 'facts'?

There's no arguments Pete, either its the GFS or the ECM handles Greenland better...that's the point. If Ian thinks GFS handles Greenland better why is he siding with ECM now? It may well be right and indeed I have one 'BIG' niggle....and that's RJS research does not support cold until end of month into Feb.....and that bothers me.

BFTP

Edited January 8, 2013 by BLAST FROM THE PAST

[Uncle_Barty]

As a real novice here, I just don't understand how 6 hours can make all the difference. Last night most posters were bullish and this morning you'd think the whole think had be cancelled. Just doesn't make sense to the casual reader.

It's the usual thing of some taking note detail of every run every 6 hours. "Upgrade! " "No, now it's a downgrade! "

Instead of looking at the bigger picture, the overall pattern, the hemispheric pattern, and knowing that there will be swings in the model output.

Overall, over the past few days, it's still a story of a good chance of a cold pattern for the UK (about 50:50 IMO), but confidence on detail is low - so there is little point on getting hung up on detail.

Edited January 8, 2013 by Uncle_Barty

[SnowBallz]

So the GFS handling Greenland better is out of the window now Ian is it because its not showing the mild outlook you seek? You are the one that quoted this when GFS was showing low heights over Greenland....on that basis I would suggest you are not being objective but seeking any outlook that suggests this and going with it.BFTP

I saw a post from Ian Brown a few days ago - only because someone quoted him, as I have him on ignore (along with a couple of others who are an equally acquired taste) - confirming that his 'analysis' consisted of essentially choosing the mildest scenario, 'as that's most likely to happen'.

Impressive stuff, very scientific; I mean, where would we be without such insight?

I think we all know that the UKs weather is pervasively Atlantic-driven, and therefore if it's a game of percentages - or if you're a bookmaker - then you'll hedge your bets to this outcome. You can have that as your 'principle', if you will, but I just find it incredibly ignorant to persist with 'the most likely scenario' even in the face of what are - fairly obviously - exceptional circumstances.

I attach more credit to the amateur meteorologists on here who have the real understanding of the weather, so much that they're confident enough to make bolder and more profound analysis, relative to the 'safe' and unimpressive obvious. By this, I refer to the excellent work from those involved in the stratosphere thread; really impressive reading, with outstanding results (viewing the rocketing SSW over the last 48hrs has been a real proof of concept )

I wouldn't expect ying-yang from the MetO advice later, as my impression is that there isn't (yet) enough tangible evidence to flip-flop between possible scenarios. I think they'll opt to play a cautious, straight bat in order to maintain relative consistency. When such time as there is greater cross-NWP consensus, then I would expect more confidence to change the general guidance.

[mcweather]

No it was the ECM that first picked up the shortwave off Southern Greenland in late November. The GFS was first to show the Norwegian shortwave in December that scuppered the Easterly.

Just really disappointed for everybody, let's see what Ian F has to say and see if the METO change their outlooks later.

As you say Ian probably best to leave it to the professionals like Ian F in a situation like this.

Oh and look here's what they think

Posted Today, 00:28

POPULAR

Very latest UKMO guidance just issued goes for the cold/v cold story predominanting into next week with potential sequence of battleground set-ups of snow to rain and back again in W/SW ; heavy snow potentially in any region; perhaps with a temporary relaxation of pattern but return of cold thereafter (MOGREPS keeping a N'rly well into 10-15d trend period)

[latitude]

It's the usual thing of some taking note detail of every run every 6 hours. "Upgrade! " "No, now it's a downgrade! "

Instead of looking at the bigger picture, the overall pattern, the hemispheric pattern, and knowing that there will be swings in the model output.

Overall, over the past few days, it's still a story of a good chance of a cold pattern for the UK (about 50:50 IMO), but confidence on detail is low - so there is little point on getting hung up on detail.

Tell that to the METO who are possibly about to change their outlook from cold and snowy last night to something more mild this morning.

As you say Ian probably best to leave it to the professionals like Ian F in a situation like this.

Oh and look here's what they think

Posted Today, 00:28

POPULAR

Very latest UKMO guidance just issued goes for the cold/v cold story predominanting into next week with potential sequence of battleground set-ups of snow to rain and back again in W/SW ; heavy snow potentially in any region; perhaps with a temporary relaxation of pattern but return of cold thereafter (MOGREPS keeping a N'rly well into 10-15d trend period)

Sorry but that update will soon be very out of date, and will not carry on the very cold snowy theme.

Edited January 8, 2013 by latitude

[mountain shadow]

Why are Ian Brown and others being critised for saying the cold snap this weekend will be brief and not sustained?. Seems to me that this agrees with the METO and last two ECM ops.

No prolonged snow and cold likely until towards the end of the month more likely given expected propogation timescales from the SSW

[nick sussex]

I think people are becoming overly obsessed with MOGREPS and the ECM 32dayer.

When you think about it they are just as likely to be wrong at day ten and onwards as the normal ensembles we see.

They don't have some magic start conditions that make them any better. We've been here before with both of those hope combos as I'd like to call them with the subsequent mood crashes in here if MOGREPS or the ECM 32dayer suggest a less than exciting wintry outlook.

The best outputs are the higher resolution operational runs upto 168hrs with at least medium term trends being picked up by day ten, yes currently they disagree but in these situations its best to try and build up a picture from earlier rather than looking for snow salvation at some outlandish timeframe.

All the outputs have early potential, we'll get to the right trend at some point, it might not be the one we want or it well might be!

Edited January 8, 2013 by nick sussex

[Methuselah]

Can we all go back to the models, please? And stop the nit-picking...

[snowbob]

Very novice look on things here

But to my untrained eye looks as though there are far to many members looking to be the first one to call the collapse of any cold

Rather than looking for any cold

There isn't even any cold here yet jeez

Sorry as you were

[bradymk]

There's no arguments Pete, either its the GFS or the ECM handles Greenland better...that's the point. If Ian thinks GFS handles Greenland better why is he siding with ECM now? It may well be right and indeed I have one 'BIG' niggle....and that's RJS research does not support cold until end of month into Feb.....and that bothers me.

BFTP

Yes RJS said on CET thread this morning that he thinks a few colder days followed by not so cold and then whatever happens in the last third but like you say, he had always said the coldest period being end of the month into Feb. Interesting to see where he stands with this. For me, another good morning for coldies however ECM and its ensembles that Matt highlighted is an issue but a great 00z run from GFS op for cold, one will have to flip soon, looking forward to the UKMO 00z guidance.

[Polar Maritime]

As it stands they suggest weekend cold block short lived; then temporary milder phase; then cold again. That was based on 12z analysis. I can't pre-judge what they'll issue based on 00z.

Ties in with the CPC charts, showing short lived block-mild blip, then something more prolonged.

On mob so no charts..

[Yarmy]

Do we have any verification stats for localised model performance? By which I mean are statements like 'GFS models Greenland better than ECM' measurable, or is it anecdotal based on chart-viewing experience?

[TAFKAP]

Tell that to the METO who are possibly about to change their outlook from cold and snowy last night to something more mild this morning.

Sorry but that update will soon be very out of date, and will not carry on the very cold snowy theme.

But given the flip flopping of late, wouldn't the Meto look very silly changing to the degree you suggest. The output could be different yet again come this evening.

[NL]

This cold 'snap' at the weekend has always been progged to be a short lived affair when it showed up in the modelling a few days ago and then a return to Atlantic driven scenarios for a week or so. The SSW event will have an effect at the surface around the 15th then the fun and games will commence.

[weather eater]

I haven't said it has changed: don't know yet!

Leaving aside the major synoptic details and just looking at the broad picture I can’t see why they would change that view, certainly the last couple of GFS runs support that prognosis and the ECM early evolution has moved towards the GFS solution, obviously they have more data to look at than we do, but I will still be very surprised.

Edited January 8, 2013 by weather eater

[Paul Sherman]

The Key word in all of this is Patience!

I know its been a hard first half of winter if it is Snow and Frost you like, but this was always going to play out like this, in fact this weekends colder blip is surely a bonus, most long range forecasts pointed towards an interesting 2nd half to January and Cold February, the point of Interest for me as has always been is the last 10 days of January and into February, which would fit in nicely with this cool down into the weekend, not so cold next week and then maybe the fun begins from the w/k of the 20th/21st January!