General Model Output Discussion

[Frosty.]

Mild air would get into the southwest with 10c reached and less cold in far southern england at the very end of next week at 4-6c, the gfs 00z shows this @ T+180 but a lot depends on the track of the low, do we really want more serious amounts of snow as the country is already paralysed by snow and ice, personally, it seems a bit OTT to be wishing for more chaos on top of the chaos we already have. I would say the odds now favour a gradual trend to less cold despite the gfs reload idea.

Edited January 9, 2010 by Frosty039

[nick sussex]

Mild air would get into the southwest with 10c reached and less cold in far southern england late next week at 4-5c but a lot depends on the track of the channel low, do we really want more serious amounts of snow as the country is already paralysed by snow and ice, personally, it seems a bit OTT to be wishing for more chaos on top of the chaos we already have. I would say the odds now favour a gradual trend to less cold despite the gfs reload idea.

I wasn't wishing for chaos i was simply reporting what the ECM showed, did you actually read my post properly! In terms of my ramp it was meant to indicate just how much snow could occur with the ECM, and if you read my post yesterday i said clearly that if this continues well into January that even cold and snow lovers might start wishing for something less cold!

In terms of disruption and chaos yes the ECM would bring this with its Channel low!

Edited January 9, 2010 by nick sussex

[Joneseye]

Just looking at latest gfs pub run... and would like to ask a quick question, mentioned this in the scotland thread and had it suggested i pop it in here for some of our experienced posters to answer:

It shows us 'warming up' to -5 850s and possibly even 0's... then it shows the -5 and colder reappearing from almost nowhere eg no draw off the continent.

Is this because the cold is so embedded over us and with the ground utterly frozen that we can quickly generate our own cold or even cool any southwest stream that may appear?

I am no expert and certainly don't know the answer to this question, but I know Nick F raised a similar point on the previous thread. This almost seems like too complicated a scenario to factor into any model guidance, however it has appeared on a couple of model runs now I believe.

[snowingman]

the midnight run is definitely an upgrade from GFS.... it has pulled back from the dramatic Atlantic over run as forecast yesterday, in fact I see our main depression threats now heading southwards into Southern Europe - leaving us in no a shallow no mans land of cold - see the upper -5 to -10s return after 7 days!

later on - suggestions that pressure will rise once more to our North - and a reload equivalent to our past 3 weeks could just be on the cards again

Remember one key point everyone - February is GENERALLY and USUALLY the month that pressure is high to our North and East - so based on this, and with the current exceptional cold - we are only 1/3rd of the way through this 1 in 30 year winter spell

LOOKS really good!

[Frosty.]

I wasn't wishing for chaos i was simply reporting what the ECM showed, did you actually read my post properly! In terms of my ramp it was meant to indicate just how much snow could occur with the ECM, and if you read my post yesterday i said clearly that if this continues well into January that even cold and snow lovers might start wishing for something less cold!

In terms of disruption and chaos yes the ECM would bring this with its Channel low!

I never said you were wishing for chaos

Anyway, the ukmo and especially the ecm are slowly trending towards a less cold pattern but in the meantime, the joy for some and misery for others will continue for around another week but longer if the gfs 00z verified.

[nick sussex]

hey nick what would gfs and ukmo bring?

The UKMO and GFS are quite different to the ECM as they bring the low towards the sw but then hold it and develop a shortwave which runs se through the sw, they would deliver snow initially away from coastal fringes of the sw but then go their separate ways after 96hrs, it's all very uncertain and I'd put FI as anything past 84hrs, unbelievable I know but there are such large model differences that we may aswell bin all the output past this point.

You see what happens this early on makes a big difference later.

Edited January 9, 2010 by nick sussex

[snow drift]

I wasn't wishing for chaos i was simply reporting what the ECM showed, did you actually read my post properly! In terms of my ramp it was meant to indicate just how much snow could occur with the ECM, and if you read my post yesterday i said clearly that if this continues well into January that even cold and snow lovers might start wishing for something less cold!

In terms of disruption and chaos yes the ECM would bring this with its Channel low!

Quite right. What people wish for has no influence on what actually occurs.

The way the models are looking, a reload is not out of the question. Just because it has been cold previously does not mean it is time for mild and south westerlies. We may get a bit of a warm up,especially down here but i can see this being pushed back down the line.

Alot to be decided, very interesting model watching.

[markg]

i think having watched all the charts over the last 3-4 days that no model seems to have a difinitive take on next week and whether or not we are going to stay cold or turn less cold after tuesday when push comes to shove the first low direction will have abig impact on any future develpoments ,times like this it may be better to stop watching every single model and run and just enjoy what we get!! weve had 22 days with snow on the ground here at sea level

Edited January 9, 2010 by markg

[snowmadchrisuk]

Quite right. What people wish for has no influence on what actually occurs.

The way the models are looking, a reload is not out of the question. Just because it has been cold previously does not mean it is time for mild and south westerlies. We may get a bit of a warm up,especially down here but i can see this being pushed back down the line.

Alot to be decided, very interesting model watching.

I'm Wishing for chaos and proud of it . All year all of us wish for on here is a channel low to dump crazy amounts of Snow on us , the possibility as Nick points out is now showing on the Models. I am sure I speak for at least 90% on here when I say we would like this to happen.

This now all comes down to how this low interacts with our High and this will decide weather the low ends up in the Channel or over Bristol. My punt is that it will around the channel and cause a big Snow event , but it will eventually drag some milder uppers in by next weekend. That by no means is a forecast though the only thing that is certain at the moment is the uncertainty .

Chris

[Nick B]

i think having watched all the charts over the last 3-4 days that no model seems to have a difinitive take on next week and whether or not we are going to stay cold or turn less cold after tuesday when push comes to shove the first low direction will have abig impact on any future develpoments ,times like this it may be better to stop watching every single model and run and just enjoy what we get 22 days with snow on the ground here at sea level

Your point is particularly relevant if you really take into consideration GP's latest contribution to the In Depth Technical Discussion thread last evening.

Enjoy it, the cold may well stay with us for some time yet. This would also echo JH's warnings to us and BFTP seems to be hinting about February though he is waiting until mid-month to let us have his prognosis...

[snowblizzard]

the midnight run is definitely an upgrade from GFS.... it has pulled back from the dramatic Atlantic over run as forecast yesterday, in fact I see our main depression threats now heading southwards into Southern Europe - leaving us in no a shallow no mans land of cold - see the upper -5 to -10s return after 7 days!

later on - suggestions that pressure will rise once more to our North - and a reload equivalent to our past 3 weeks could just be on the cards again

Remember one key point everyone - February is GENERALLY and USUALLY the month that pressure is high to our North and East - so based on this, and with the current exceptional cold - we are only 1/3rd of the way through this 1 in 30 year winter spell

LOOKS really good!

But this appears not to be a normal or usual year for weather patterns!

Edited January 9, 2010 by snowblizzard

[Rollo]

I believe GP said there would be great model uncertainty over the next few days and indeed that appears to be happening-looking forward I think that overall after a slight relaxation in the cold it will return.It would take a big rise in temperature to shift the 14" of ice and snow we have here.

[PB22]

Very interesting week ahead, and very uncertain times. I would think it will turn somewhat milder in the south later in the week, especially towards the southwest. However, we have that very cold feed coming in off the continent and history shows this can take some shifting. For many areas I would suggest it will remain cold or very cold until midweek at least...

[Duane S.]

I'm Wishing for chaos and proud of it . All year all of us wish for on here is a channel low to dump crazy amounts of Snow on us , the possibility as Nick points out is now showing on the Models. I am sure I speak for at least 90% on here when I say we would like this to happen.

This now all comes down to how this low interacts with our High and this will decide weather the low ends up in the Channel or over Bristol. My punt is that it will around the channel and cause a big Snow event , but it will eventually drag some milder uppers in by next weekend. That by no means is a forecast though the only thing that is certain at the moment is the uncertainty .

Chris

Chaos please. And if those up North are fed up with it, I'll willingly take it on

The track of this low is going to chop and change all over the place until about T+6. It has the air of a classic Atlantic attack though. Send in the 'front line' low to weaken us, then the 'cavalry' low to finish off us BUT... what a battle it could be!

If the last snow dumping was a forecasters nighmare, I don't know what this scenario is. The METO will be wary about playing it down as there is the potential of a massive dumping from this system in the South of England. Even on the coast, with the right conditions, this could be snow and a LOT of it. There reamins the possibility that a warm front, which will probably become occluded will be drawing up much milder and very moist air from the Biscay. When this interacts with the cold air, expect fireworks.

Edited January 9, 2010 by s4lancia

[Tuxedo]

I'm not a regular poster on her but I do enjoy reading all the posts. I have done so for many years and have learnt much. Its a forum we can all be proud of and enjoy...So a huge thankyou to all the regulars here who have such knowledge and opinions about how our weather works.

I cant begin to add more to what has already been said about what the current models are battling with. I dont have the scientific background or knowledge...However i thought this currently sums up the current model situation but in aless scientific approach:-

The ECM and GFS are all a mess

They cant agree on the low out West

You see its typical of meteorology

Posters views go up and down with probability

There's the Nicks,Eyes in the Skies and even one called Glacier Point

They all have there views of this low west of Hinkly Point.

But know one really knows

If it goes south... well it snows!

If it goes north...

it rains of course.

But wait. Is that a Greeny High

I see from the corner of my eye?

Sorry mods if you think its off topic but it kind of sums up what the models are showing!

[ANYWEATHER]

For those hoping for a quick change to milder weather dont look at the latest outputs! With deep surface cold over much of NorthWestern Europe and the UK the battle lines are clearly drawn if one for instance looks at the latest gfs. It would not be a surprize to me that this coming week some places in the south of the Uk will be literally buried in deep deep snow, perhaps rivalling snowy Winters to the likes of 1947?! A THAW.?? It looks as though the 850s get mixed out and diluted a bit but with a contenental feed that should help most of the precip to be snow, although the far sw could see cold rain for a while. The very cold air right through the gfs run is never to far away from the uk so perhaps a new reload of artic air coming soon after the heavy snowfalls of the coming week.Whatever way you look at it this is "classic winter " stuff the likes of which the uk has not seen for decades, but a truly "forecasters nightmare" Enjoy if you can!!

[snowmadchrisuk]

I'm not a regular poster on her but I do enjoy reading all the posts. I have done so for many years and have learnt much. Its a forum we can all be proud of and enjoy...So a huge thankyou to all the regulars here who have such knowledge and opinions about how our weather works.

I cant begin to add more to what has already been said about what the current models are battling with. I dont have the scientific background or knowledge...However i thought this currently sums up the current model situation but in aless scientific approach:-

The ECM and GFS are all a mess

They cant agree on the low out West

You see its typical of meteorology

Posters views go up and down with probability

There's the Nicks,Eyes in the Skies and even one called Glacier Point

They all have there views of this low west of Hinkly Point.

But know one really knows

If it goes south... well it snows!

If it goes north...

it rains of course.

But wait. Is that a Greeny High

I see from the corner of my eye?

Sorry mods if you think its off topic but it kind of sums up what the models are showing!

I would say that is rather well put .. You should post more often . :lol: The 6z is just starting to come out .. can't wait to see where the low ends up this time . :wacko:

[Frosty.]

Very interesting week ahead, and very uncertain times. I would think it will turn somewhat milder in the south later in the week, especially towards the southwest. However, we have that very cold feed coming in off the continent and history shows this can take some shifting. For many areas I would suggest it will remain cold or very cold until midweek at least...

Hi paul,

I think it's on a knife-edge as next week progresses, some slackening of the intense cold seems likely later next week but how far will the less cold/milder air encroach is the big question this morning and more severe snowfalls are going to occur in the meantime, this weekend looks very bad for most of southern britain and more heavy disruptive snowfalls during next week as low pressure moves northeast into the deep pool of very cold air over the uk, probably 50/50 at this stage with the gem & gfs going for continued cold but the ecm and ukmo suggesting less cold further out but all subject to changes.

[benb]

Chaos please. And if those up North are fed up with it, I'll willingly take it on

The track of this low is going to chop and change all over the place until about T+6. It has the air of a classic Atlantic attack though. Send in the 'front line' low to weaken us, then the 'cavalry' low to finish off us BUT... what a battle it could be!

If the last snow dumping was a forecasters nighmare, I don't know what this scenario is. The METO will be wary about playing it down as there is the potential of a massive dumping from this system in the South of England. Even on the coast, with the right conditions, this could be snow and a LOT of it. There reamins the possibility that a warm front, which will probably become occluded will be drawing up much milder and very moist air from the Biscay. When this interacts with the cold air, expect fireworks.

Great post!

I think that sums up the spirit that many of us watch the models for.

The difference this time round is that the dream scenario isn't hundreds of hours away and never likely to happen.

Of course, it could be rain, not snow, across the South. But that's what's so engrossing about this situation.

Having studied all the avaliable data: I think it's 50/50!

[Solar Cycles]

For those hoping for a quick change to milder weather dont look at the latest outputs! :wacko: With deep surface cold over much of NorthWestern Europe and the UK the battle lines are clearly drawn if one for instance looks at the latest gfs. It would not be a surprize to me that this coming week some places in the south of the Uk will be literally buried in deep deep snow, perhaps rivalling snowy Winters to the likes of 1947?! A THAW.?? It looks as though the 850s get mixed out and diluted a bit but with a contenental feed that should help most of the precip to be snow, although the far sw could see cold rain for a while. The very cold air right through the gfs run is never to far away from the uk so perhaps a new reload of artic air coming soon after the heavy snowfalls of the coming week.Whatever way you look at it this is "classic winter " stuff the likes of which the uk has not seen for decades, but a truly "forecasters nightmare" Enjoy if you can!! :lol: :lol:

I'll go along with that, to me it looks like a big snow event from the Midlands to Northern England. This block is going no where in the next week or two, less cold air for the SW and the far South of England, with a mixture of rain/sleet there. Towards the end of next week, Arctic air re-establishes itself over the whole country!

[Harsh Climate]

Its no coincidence that the chance of a breakdown/ return to milder weather coincides with a forecast for rising NAO/AO to near zero, rather than being well NEGATIVE.

http://www.cpc.noaa.gov/products/precip/CWlink/pna/nao.mrf.gif

http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

If you look at the past weather weve had, its all being with the telleconections being very negative. And for such an exceptional/prolonged cold spell that weve had, these are absolutly esential.

Im not saying a breakdown/mild is inevitable just that a another greeny high or retrogressing towards that area is very unlikly now. I think If we can just hang on to the cold in the form of a scandi type high/ a euro high that streches pretty far north, we may just hold off the atlantic in time for more WAA to be pumped towards greenland increasing the chances of a real block :wacko:

The chances of huge snowfalls will be increasing next week, but as ever the risk of a breakdown to mild. If I had it my way Id perhaps prefer more of the same, less of a gamble (says a guy who likes a gamble.)

Hopefully the dream scenario will be, heavy snow pushing in from the atlantic, but just as the milder air is about to turn the snow to rain, it gets edged southwards followed by a chilly night and high pressure from the east

[MR EXTREMES]

Chaos please. And if those up North are fed up with it, I'll willingly take it on

The track of this low is going to chop and change all over the place until about T+6. It has the air of a classic Atlantic attack though. Send in the 'front line' low to weaken us, then the 'cavalry' low to finish off us BUT... what a battle it could be!

If the last snow dumping was a forecasters nighmare, I don't know what this scenario is. The METO will be wary about playing it down as there is the potential of a massive dumping from this system in the South of England. Even on the coast, with the right conditions, this could be snow and a LOT of it. There reamins the possibility that a warm front, which will probably become occluded will be drawing up much milder and very moist air from the Biscay. When this interacts with the cold air, expect fireworks.

spot on gp is excellent at what he does and jh along with bftp.

theres absolutely every chance of a very big snow event remember this system has come from a cold source,

also tracked over a not very warm alantic,

its not like it came from tropical part of the alantic theres plenty of cold in the nh.

along with this i think theres much more to come even with a slight warm up,

and every model is not suggesting anything higher than average reload looks very possible.

i was wondering is there a chance of this low pressure starting of as snow or is it very marginal?.

[Harsh Climate]

I think the next cause for concern from the met office will be sunday evening/through monday in more central parts of the UK..

http://www.wetterzentrale.de/pics/Rtavn424.png

http://www.wetterzentrale.de/pics/Rtavn664.png

No suprise when you have cold easterly winds traveliing over a mildish north sea.. I think a long spell of light/moderate snow rather than heavy snow

[Mark Parsons]

Great post!

I think that sums up the spirit that many of us watch the models for.

The difference this time round is that the dream scenario isn't hundreds of hours away and never likely to happen.

Of course, it could be rain, not snow, across the South. But that's what's so engrossing about this situation.

Having studied all the avaliable data: I think it's 50/50!

Most break downs are a damp squib for many only a few have been exceptionally wide spread snow events, dont think this break down will go into the record books!!

[AtlanticFlamethrower]

00z GME T132 returns to an evolution that's appeared on last few GME, GEM and JMA runs but not yet on main models. Low reduced in strength, further south, block stronger, further west.