Winter Model Discussion 18Z 5/2/13 onwards.

[Stu_London]

In Northerly airstreams, There are a few weak polar lows most years that never make any sort of landfall. It's been a fair few years since we took a direct hit from one that really developed

[Ryan Dutch Weatherman]

Look i saw alle the models 00z .

I could be wrong , i admit there is lot of uncertain.

But wen i have my life or money on it i would choose this in the weather roulette models.

This one is gone be worked out i think.

Its just like januari little bit.

Thats my true opinion .

I could be wrong , but thats the way forward , i believe CMA 00z at 216 hours.

End maybe some experts can for you people explain wat this chart means , becouse i cannot express my self good in your language in weather jargon.

[Matty M]

What staggers me is that in a couple of weeks, months or years at least 30% of the regular contributors to this thread will be singing the praises of the ECM and how it superbly handled the Feb 2013 cold snap. What rubbish - I don't even buy that it's been that consistent. Last Thursday or Friday when IanF posted that MOGREPS was showing potential frontal snow for this weekend, the ECM was just bringing an easterly. UKMO showed the slider first and the ECM jumped all over it. It's difficult to rate a model that you can't see but it seems that MOGREPS was the only one that got near to the likely pattern early on. Perhaps Ian might let us know if it has been consistent after the initial early view of this weekend

It is fact that the ECM EPS suite is the most accurate probabilistic model in the world (that is open to the public), perhaps the US or Chinese military run something bigger but highly unlikely.

You are perhaps being blinded by the ECM OP. You are comparing the MOGREPS to the ECM OP, when comparison should be drawn from the ECM EPS to MOGREPS and the ECM is more accurate although obviously at times will fail.

It is too simple to target one model at a certain instance, all output should be used collectively to develop the greatest of all Ensemble tools. That is the way forward.

There should be no this model versus that model.

Also, MOGREPS is not far behind the ECM EPS.

Edited February 6, 2013 by Matty M

[SMU]

What staggers me is that in a couple of weeks, months or years at least 30% of the regular contributors to this thread will be singing the praises of the ECM and how it superbly handled the Feb 2013 cold snap. What rubbish - I don't even buy that it's been that consistent. Last Thursday or Friday when IanF posted that MOGREPS was showing potential frontal snow for this weekend, the ECM was just bringing an easterly. UKMO showed the slider first and the ECM jumped all over it. It's difficult to rate a model that you can't see but it seems that MOGREPS was the only one that got near to the likely pattern early on. Perhaps Ian might let us know if it has been consistent after the initial early view of this weekend

I Must admit stu I get irritated so much by posts like this that are at best misguided - at worst deliverate baiting.

The ECM has had the sliding low scenario for probably the last 5 days.

What do you think frontal snow is?? & whats difference between that & what the MOGREPS shows.

The GFS has been hopeless, worse than hopeless its been owned by the NOGAPS & probably on occasion any other insignificant models. Its been like a 5 year old holding a gatling gun firing bullets in all random directions occasionally one may be close.

When the UKMO came in range at 144 it has mirrored the ECM with the PATTERN.- small height increases to the North & a sliding low scenario- the only difference being the UKMO has been @ 200 Miles East & at day 6 thats well within an acceptable margin of error.

Whats annoyed people this morning is the ECM isnt suddenly showing prolonged cold past 168- so suddenly its been wrong all the way through-?

No, its just showing some volatility at 192 onwards based around differing solutions.

I do wonder whether i can even be bothered to post on here when people who I would call regular post some flame posts when really they should know better.

The Euros have toned down the cold ever so slightly today at day 6 with higher heights over the back of the low- thats not a full on fail, just a modification- sometimes things work in our favour, sometimes they work against us & if this is the case what was once a chart with low heights & heavy snowers for the SE is now a slacker flow with light showers.

I think I will retreat to my regional thread.-

Edited February 6, 2013 by Steve Murr

[Ryan Dutch Weatherman]

An After the 216 chart, see the 240 hours CMA 00z.

He is locking UK in a jail.

A cold pool , this means lot of snow , many hours.

This chart is the snow run of the century for the UK if iets becomes true.

I repeat ;

This chart is the snow run of the century for the UK if iets becomes true.

Perfect snow.

From the north to the south , from dublin bis wales, from low level tot highground , even the above the noord sea , irisch sea.

I am just telling wat this chart means , dont be angry to me please.

End look the links of the Hogedruk between a widespread scale , surrounding UK with a COLD POOL.

[SLEETY]

Glacier point .You did make a good point with the ensembles from GFS.

But look the BOM model , its great run.

A block , a NE wind , end a POLAR low is sinking from the north towards the UK.

This you can print it out en hang it at your living room.

Yes that is the chart that dreams are made off!!

From that position the low would sink SW and the high migrate NW,and we would probably end up with something similar to this!!

If you ever want a chart to verify it's that bom chart!!

[TEITS]

What staggers me is that in a couple of weeks, months or years at least 30% of the regular contributors to this thread will be singing the praises of the ECM and how it superbly handled the Feb 2013 cold snap. What rubbish - I don't even buy that it's been that consistent. Last Thursday or Friday when IanF posted that MOGREPS was showing potential frontal snow for this weekend, the ECM was just bringing an easterly. UKMO showed the slider first and the ECM jumped all over it. It's difficult to rate a model that you can't see but it seems that MOGREPS was the only one that got near to the likely pattern early on. Perhaps Ian might let us know if it has been consistent after the initial early view of this weekend

Very odd post considering the ECM goes out to +240 and the UKMO only +144!!

The ECM first picked up on the slider on the 1st Feb on its 0Z run.

[I remember Atlantic 252]

06Z definitely has everything further west, just wanna avoid my washout Sunday, 06Z looks like rain will arrive sunday evening

[shaky]

06Z definitely has everything further west, just wanna avoid my washout Sunday, 06Z looks like rain will arrive sunday evening

Which means the colder air is further west hopefully and a greater chance of a snow event??

[Severe Siberian icy blast]

Just to highlight the uncertainty of this wkend if we look at yesterday's ECM 12z

We can see the angle of attack is perfect for a big snow event across a large swathe of the uk.

Then if we look at this mornings 0z , again on the ECM

Although we don't have 12 hours charts to get the exact match , we can see the low is sitting a bit different that has big amplifications on our weather , with the coldest air not embedded as well as the core of the low passes through , slight differences will mean the difference between rain or snow .

Which one is right?

Well the truth is know one knows , and come this evening things will change again for better or for worse , but this wkend is still a long way off in weather terms , and I won't be surprised to see many changes over the next 4 days or so.

Shaun

[TEITS]

06Z definitely has everything further west, just wanna avoid my washout Sunday, 06Z looks like rain will arrive sunday evening

Clearly shows how difficult this period is to forecast. Apart from the obvious shift E & W we are seeing the angle of the LP is another factor. As the period in question is still +96hrs away I feel we have another 48hrs of modelling uncertainty.

Which means the colder air is further west hopefully and a greater chance of a snow event??

No not always. Could be the shift W means the precip doesn't even reach our area!

Edited February 6, 2013 by THE EYE IN THE SKY

[SMU]

Finally some -10s showing up on the Fail model. not bad for T96 onwards only 3-5 days behind the euros.

S

[shaky]

Finally some -10s showing up on the Fail model. not bad for T96 onwards only 3-5 days behind the euros.

S

unbelievable now the gfs is more progressive in bringing in the cold!!and the ecmwf goes slightly tits up!!

[TEITS]

http://modeles.meteo...gfs-1-114.png?6

Finally some -10s showing up on the Fail model. not bad for T96 onwards only 3-5 days behind the euros.

S

Question is do you feel some will learn from this next winter?

Probably not. A very poor winter generally for the GFS.

[Methuselah]

Oh dear! Why do so many folks still persist in 'supporting' models, as though they were football teams?

[snowice]

http://modeles.meteo...gfs-1-114.png?6

Finally some -10s showing up on the Fail model. not bad for T96 onwards only 3-5 days behind the euros.

S

IF you dont trust the gfs,and its a failed Model -10uppers wont come off!

[SMU]

Oh dear! Why do so many folks still persist in 'supporting' models, as though they were football teams?

Surley its best to follow a model thats the best.- which is nothing like football ( well unless you just support the best team )Following the models in terms of the 3 is like following Man U, Man C & QPR in the cup-Once every 10 years QPR will beat Man U- however doesnt make it better.Perhaps someone should post up all the 00z & 12z for thr last 5 days for the 10th of Feb-I think people would actually be astonished at how bad the GFS is.S

IF you dont trust the gfs,and its a failed Model -10uppers wont come off!

Its near identical to the UKMo- hence the catch up comment.S

[Snowman.]

Would like to see some real good convection snowfall for me but that chance may be slipping but like yesterday the 12z picked back up with a good ecm

[nick sussex]

Any chance that shortwave to the nw of Scotland could take a hike. This is a real nuisance and just sits there waiting to phase with the next upstream low.

I don't understand why the energy just cant clear cleanly se allowing the ridge to the east to extend further west. Perhaps this stinky cold I've had for days is now effecting my brain but I don't see why this shortwave decides to just sit there.

[Skyraker]

http://modeles.meteo...gfs-1-114.png?6

Finally some -10s showing up on the Fail model. not bad for T96 onwards only 3-5 days behind the euros.

S

Can't you hear the Benny Hill music in the background as the GFS rolls out?

[SLEETY]

lol how many times have we seen this before.

the ecm backtracks ,and the gfs after faffing about for days comes on board and shows even greater cold coming!!

[lord stratus]

06Z definitely has everything further west, just wanna avoid my washout Sunday, 06Z looks like rain will arrive sunday evening

If I had a pound for the everything further west quote I would be a rich man!

[Methuselah]

If I had a pound for the everything further west quote I would be a rich man!

And Bermuda would be under -10C uppers!

[lord stratus]

And Bermuda would be under -10C uppers!

Lol

[mulzy]

Just catching up after a quick scan through the models and I am surprised by some of the posts. It seems we are forever discussing beyind t168 and forgetting about anything before which is far from settled and very interesting. As far as I can see for the majority of areas the slight eastwards shift of the low on Sunday and the slight change in shape is an upgrade for the majority in terms of snow (not for the SW). Last night as per IF post most of the snow was predicted for the SW, Wales, WM and west country. Now it seems it is much more extensive as shown by the extent of the 850 -5 isotherm and precipitation maps (I know there are other factors).

The maximum extent of the -5 line is the England Wales border and W of the IoW. Extensive precipitation beyond to the E.

You can also see the precipitation associated with the Shortwave of the coast of Norway on the last frame. You can also see the -10 air running into the E coast.

So as far as I can see it looks like an improvement for many on this run. Beyond that is intereting to discuss but is just FI and not worth worrying about as it will change. Best to use the mean anomalies as GP pointed out.

I think the 850 charts relate to yesterday evening's run while the precipation charts relate to this morning's runs.