winter model output Winter Model Output Discussion -12Z 07/02/13 onwards

[Man With Beard]

Ian's latest posts. Is this what you was refering to?

Key thing perhaps being overlooked in some MOD thread discussion is nocturnal chilling of boundary layer versus what 850's show per se. RegIonal modelling of lowest boundary layer currently beyond reliable scope of GM models for Sun night.

Latest modified GM for 12z Sun. Compare to FAX. Takes ensemble mean position. Note rain-snow discrimination thro Somerset etc is clearly clearly not to be taken literally at this range. Shorter sea track further E on S Coast enhances snow potential, as per event in Jan.

I think this METO map is a very fair reflection of what all of the output is saying - it seems the middle route. I sense an air of despondency here following the ECM tonight - though of course it may end being the actual outcome, I see it as no more than one extreme of the possibilities in terms of how deep the low will get. I don't see any chance it will be deeper and, going by recent experience of forecasted deep lows from all models, I see a big chance that it will get shallower.

[Weathizard]

ECM big outlier in later timeframes so going to ignore that as I would if it was a big cold outlier. Not writing it off because its a plausible if slightly strange looking run after 144. Interestingly there has been big swings in the past 48hrs in the ENS to a colder outlook medium range which is always of interest, and with the progged shift of energy from Greenland the lesser spotted (I won't say it) could be possible within 10 days I feel.

[Long haul to mild]

I think this METO map is a very fair reflection of what all of the output is saying - it seems the middle route. I sense an air of despondency here following the ECM tonight - though of course it may end being the actual outcome, I see it as no more than one extreme of the possibilities in terms of how deep the low will get. I don't see any chance it will be deeper and, going by recent experience of forecasted deep lows from all models, I see a big chance that it will get shallower.

Absolutely agree with this. UKMO, FAX, and the posts from Fergie all suggest that it will not be as deep as the ECM suggests. Recently the ECM has been caught out with blowing up lows at short timeframes (last Friday for instance as per my earlier post) so although we cannot discount it as a possibility, I still think it unlikely.

[bluearmy]

Naefs update pretty amazing - note the mode uppers for 22/2 of -7.5c london!

IF we can get a widespread snowfall and avoid a strong thaw through next week, we could be looking at a sustained surface cold period with a slackish euro trough engulfing us. Currently, we look to be on the edge of the cold which i suspect will see the troughs heading nw/se across parts of the uk. that would surely deliver copious amounts of snowfall to some areas. Higher ground favoured as per usual.

[goosey007]

I think this METO map is a very fair reflection of what all of the output is saying - it seems the middle route. I sense an air of despondency here following the ECM tonight - though of course it may end being the actual outcome, I see it as no more than one extreme of the possibilities in terms of how deep the low will get. I don't see any chance it will be deeper and, going by recent experience of forecasted deep lows from all models, I see a big chance that it will get shallower.

this meto map is interesting......anybody got a key for the different symbols some strange ones on there......

[Snowman.]

Already a shift NE causing most of EA to miss out.

Still clearly not decided.

[bluearmy]

this meto map is interesting......anybody got a key for the different symbols some strange ones on there......

Basically, circles are rain and crosses are snow.

[shaky]

Already a shift NE causing most of EA to miss out.

Still clearly not decided.

Shift ne??wouldnt that put east anglia in the firing line!!am sure the 12z was slightly further west!!

[snowking]

ECM 12z snowfall potential roundup

Deterministic has the snow line from roughly Aberystwyth - Lowestoft north

Control has it north of a line from Southampton - Cardigan

So, in terms of the Sunday-Monday event, the control has the main bulk of the snowfall for N Ireland, most of Wales, the Midlands, and then down to East Anglia/South-East (similar idea to UKMO/GFS 12z)

The op, on the other hand, has it mostly across North Wales, North Midlands, Norfolk/N Cambridgeshire, Lincolnshire, Yorkshire and Lancashire, as well as N Ireland.

The op looks to be an outlier against the rest of the available model data in that respect (including the UKMO GM/Arpege from what Ian has suggested), but obviously as the highest res output it cannot be discounted

Nick will have to see if his Prozac wholesaler can get some paracetamol in for the next few days

SK

[Hammer]

Already a shift NE causing most of EA to miss out.

Still clearly not decided.

Could you expand on your thoughts, as to what you are referring.

[Pembroke Dangler]

After looking at exeters modified fax postet by fergie in the southwest thread, it would seem that the trough will disrupt earlier probably over Southern Ireland and head se very similar to the January event which blanketed most of wales and West Midlands, it's a trend to see westward corrections again, and also the Siberian high is moved further west also as the catalyst for the earlier disruption, could be that this set up could be vertually identical to the January event! Although stronger heights to the northeast being the only major difference on this occasion!

Dp getting lower as the front stalls over the sw caused by easterlys from the continent so rain turning to snow rapidly as the cold air undercuts from the south east and once again wales and West Midlands and southwest England could get a dumping baring maybe the south west coast say west of Plymouth again!

Talk about déjà vu!

[Snowman.]

Washout for the south.

Could you expand on your thoughts, as to what you are referring.

GFS 18z

Pushes the low NE

18z

12z

Edited February 7, 2013 by SN0WM4N

[shaky]

ECM 12z snowfall potential roundup

Deterministic has the snow line from roughly Aberystwyth - Lowestoft north

Control has it north of a line from Southampton - Cardigan

So, in terms of the Sunday-Monday event, the control has the main bulk of the snowfall for N Ireland, most of Wales, the Midlands, and then down to East Anglia/South-East (similar idea to UKMO/GFS 12z)

The op, on the other hand, has it mostly across North Wales, North Midlands, Norfolk/N Cambridgeshire, Lincolnshire, Yorkshire and Lancashire, as well as N Ireland.

The op looks to be an outlier against the rest of the available model data in that respect (including the UKMO GM/Arpege from what Ian has suggested), but obviously as the highest res output it cannot be discounted

Nick will have to see if his Prozac wholesaler can get some paracetamol in for the next few days

SK

Midlands looks to be in a quiete a sweet spot at the moment!!long may it continue like that!!oh and is that snow from the start the ecmwf is showing or rain to snow??

[Brett Mac]

Hi peeps im new to this forum and been watching with interest for a while now can anyone help me on how to read charts etc

[I remember Atlantic 252]

Midlands looks to be in a quiete a sweet spot at the moment!!long may it continue like that!!oh and is that snow from the start the ecmwf is showing or rain to snow??

not on 18Z it dosent, its pants for south of yorkshire

[goosey007]

Basically, circles are rain and crosses are snow.

yeah i know ive risked comming across as simple......i was talking more about the triangles and colour codes green circles and blue......

[Ryan Dutch Weatherman]

Now it is getting realy interesting by CMA 12z , .

Look at this , we see a High 1040 HP , but look the color in there in the core of center.Uou see he is filling ist wit stabiel air massa.

Make him strong.He is getiiing yellow colloured litlle bit.

But tha wat , ANOTHER glide low dooming up.

Wat the hell is going on.

It seems to me a trilla from manilla by the weathermodels.

Stay tuned for more breaking weathermodel news , i think we are up to something very big like prof DR jennifer told us from the United States. Or it wil be nothing.

The battle with the polar bear or a dream , a hoax ?

Soon we will find out.

The Polar Bear is loading hin self up for the attack , the invasion of brittain , a army of Polar Bears is ready.

[Mr_Pessimistic]

Already a shift NE causing most of EA to miss out.

Still clearly not decided.

You should know by now that e/a will miss out!!

[Long haul to mild]

To be honest the GFS is poor for snow everywhere away from high ground on Sunday / Monday.

But ultimately it's only the 18z and I shall continue to follow FAX,UKMO and NAE when it comes into range.

Still all up for grabs!

[BorrisB77]

not on 18Z it dosent, its pants for south of yorkshire

looking at the chart that SNOWMAN just posted I would say Mids are in a favourable place.

[on the coast]

To be honest the GFS is poor for snow everywhere away from high ground on Sunday / Monday.

But ultimately it's only the 18z and I shall continue to follow FAX,UKMO and NAE when it comes into range.

Still all up for grabs!

Agree poor run up to 96 hours.The track of that low not playing ball.

[EML Network]

Personally, I think this is another case of being led up the garden path.

both the ECM and GFS have the Low inflating right over the UK, stalling, mixing out the cold air.

I doubt anywhere in the South or even Midlands are going to see any snow from this on Sunday or Monday day time, by which time the precipitation will likely fizzle out.

Sorry but from where I'm sitting this is likely to be a huge disappointment for many

[shaky]

To be honest the GFS is poor for snow everywhere away from high ground on Sunday / Monday.

But ultimately it's only the 18z and I shall continue to follow FAX,UKMO and NAE when it comes into range.

Still all up for grabs!

Am telling you now the ecmwf has got the handling of the shortwave a lot better!!the fax charts are way to far south west for my liking

[Long haul to mild]

Pub run is off on one now. It elongates the low and then spawns a secondary feature so we don't get the NE or E flow across the South, although it looks interesting for Scotland!

New trend or just the GFS going a bit mad? I know which one I favour!

[on the coast]

Snowfest Monday night through Tuesday for some if 18z was to verify which it wont!!