Model Output Discussion

[Guest North Sea Snow Convection]

That pattern could last quite a while too, there doesn't seem to be any signals suggesting either a return to wortwhile cold or mild. This pattern sort of reminds me of the pattern we had to endure in summer 2008, albeit from a slightly different set of circumstances.

In my opinion I would take mild and drizzle any day over the pattern that's programmed currently.. let's hope it changes somewhat to either one with a higher chance of snow, or one to a chance of some 'Spring'' warmth.

Whilst I would obviously very much differ from you in terms of preferred options to the cyclonic pattern suggested next week, I do agree that it could last a while, and from the pov of those of us who want to see more properly cold weather and snow then it is a frustrating return when taking into account the backgroud factors of -AO, an MMW, shredded vortex and northern blocking.

Still, I know I shouldn't be complaining really, after the wonderful snow of the last day or so! But you are always left wanting more, more ,more!

North Sea snow withdrawl syndome kicking in already!

[Snowyowl9]

Initially yes - as I was just saying, the residual surface cold and a draw of air from France will be condusive for the snow that is suggested for Tuesday. Unfortuantely after that the pattern is just cyclonic and temps and dewpoints will go just the wrong side of marginal for many places, most especially in the south, without a fresh source of upper cold air to draw on.

GFS 0z run brought the low further south and gave Cold NE-lys and snow chances increased,models just have no idea where to place this low.

UKMO is the better alternative seems very consistent on where this low is going GFS 6z and ECM 0z which will look totaly different on the 12z.

http://www.wzkarten.de/pics/Rukm1201.gif

[Guest North Sea Snow Convection]

GFS 0z run brought the low further south and gave Cold NE-lys and snow chances increased,models just have no idea where to place this low.

UKMO is the better alternative seems very consistent on where this low is going GFS 6z and ECM 0z which will look totaly different on the 12z.

http://www.wzkarten....cs/Rukm1201.gif

Yes, I have based my own thoughts around the METO fax which has been in line, so far, with their own model up to t120. That shows where cold air can be sourced from to maintain some snow initially. It is quite conceivable that the models have called it wrong beyond this time and that the low will indeed be pushed in the right direction. So far that has not occured with any conviction, but fingers crossed maybe it will soon

Edited February 12, 2010 by North Sea Snow Convection

[chionomaniac]

The angulation and speed of retrogression of the withdrawing high has changed in the last day or so. This has allowed a larger wedge of milder air to become drawn into the approaching low which reduces the chance for those marginal snow situations. This could change again over the next day or so again.

[snowray]

The Met O advisory is simply due to the fax chart at +84.

http://www.wetterzentrale.de/pics/brack2a.gif

As the front moves E it could turn to snow during Tues. However at this range I would be amazed if the fax chart for Tues remains unchanged.

I'm quite convinced now that the UKMO T84 fax option is the only get out clause for a continuation of interest next weeks for our cold and snow weather entourage.

It's far to late now for the low to be further East, and at any rate the blast of cold uppers that we were looking at a couple of days ago are simply not there any longer.

Why is this? Well originally we were looking at a big clump of the PV tumbling down over the country, and although uppers still remained marginal for some areas, this was compensated for by thicknesses, intensity of PPN, evaporative cooling and DP's making things look very interesting indeed for the whole country.

All that we are looking at now is a little LP system moving South with an elongated shape (from the afore mentioned Fax) as opposed to the shape of the low favoured by GFS, and its position further East.

If this feature manages to swing South/South East, areas to the East of the LP may well end up with just enogh cold air being dragged in on a South Easterly from the cold continent to produce snow. The knock on effect might even be that the low might end up moving East, a bit like a channel low, thus introducing the colder air back over the whole of the UK by the end of next week.

My first ever Meteorology book, which was already old when I found it in the library (1950's) said: Beware of a South/South Easterly from a cold continent in late Winters, can produce heavy snowfall in the East and South East. :unsure:

Edited February 12, 2010 by snowray

[Cheese Rice]

I think a fair assessment of next week is wintry, there will be alot of rain sleet and snow around, the best places look to be inland high up. I don't know why there are some negative posts, I think this will be a very interesting week and with a unfamiliar setup (low pressure moving down from the south) anything could happen.

[cuckoo]

This chart kind of sums up my feelings about February so far. Despite favourable synoptics with a southerly jet and high pressure area over Greenland the cold air seems to be all around us but not over us.

It was a similar story last week with the high pressure to our NW looking likely to expose us to a significant easterly but it became too close to us resulting in a slack flow and the majority of the cold air slipping away into France and Germany.

Still I've not given up hope yet and will be looking at the 12Z and following the expert analysis in this thread.

[Thundery wintry showers]

I must be reading the charts differently to everyone else then! According to both ECM and GFS a cyclonic regime hangs around the UK from Tuesday onwards and the end result, following a frontal clearance on Tuesday, would be a bright, showery modified polar regime like that of 8-16 April 2008- check out the GFS Precipitation outputs for example which suggest primarily convective precipitation.

Although most shower activity is generated over the sea at this time of year, it increasingly becomes feasible to get a bit of homegrown convection in unstable setups as we head through February and I would expect some to arise mid to late next week if the current outputs verify. Showers would most likely be a wintry mix of rain, hail, sleet and snow.

Of course it is hard to pin down at this stage and such a cyclonic regime can easily turn into a dull wet spell if frontal systems turn up over the British Isles as we get nearer the time, but I'm seeing a lot of comments along the lines "nothing interesting in the outlook regardless of your weather preferences" and this simply isn't the case. Perhaps we're seeing an over-reaction to the reality that widespread lasting snow cover at low levels is looking unlikely.

[Cheese Rice]

That pattern could last quite a while too, there doesn't seem to be any signals suggesting either a return to wortwhile cold or mild. This pattern sort of reminds me of the pattern we had to endure in summer 2008, albeit from a slightly different set of circumstances.

In my opinion I would take mild and drizzle any day over the pattern that's programmed currently.. let's hope it changes somewhat to either one with a higher chance of snow, or one to a chance of some 'Spring'' warmth.

The pattern isn't even bad, I really don't see what the problem is? The outlook looks very wintry, everywhere will see snow at some point.

[snowray]

This chart kind of sums up my feelings about February so far. Despite favourable synoptics with a southerly jet and high pressure area over Greenland the cold air seems to be all around us but not over us.

It was a similar story last week with the high pressure to our NW looking likely to expose us to a significant easterly but it became too close to us resulting in a slack flow and the majority of the cold air slipping away into France and Germany.

Still I've not given up hope yet and will be looking at the 12Z and following the expert analysis in this thread.

How very true cuckoo, its charts like that that make me feel very sick indeed. Don't take much working out though that a small shift will make all the difference in the world.

Hence the idea that if next weeks LP cant be further East, then let if go even further West of the UK, but then sink South, not just end up not knowing what to do next for about a week!

In fact, if it were to end up West, East, or South of us for about a week things could get very interesting, but NOT over us!

Feel that the last few GFS runs have just been lacking direction, 12z might be the run to inspire us a bit this afternoon since it is often the trend setter. But was completely wrong with the recent Easterly, consistantly progging the HP further North, 18z turned out to be spot on in the end since it had always shown the Easterly to just clip the far SE.

Edited February 12, 2010 by snowray

[lukemc]

Hi,

Just expanding on what I said before does the outlook for next week in any way resemble that of March 2006? And if not then surely I would think that we could be in a pattern like that further down the line? Could we see another major "battleground" snow event before the winter is out? I am saying this because some tell me that the March 2006 event that resulted in substantial snowfall in my part of the world was also very marginal (with realitivly high uppers) like a lot of events like that are does anyone know what the models where predicting in the run up to that event? Because of that would it still be possible for the models to go back in our favour? Also is it true that the models have backed away from a -NAO too far west scenario that was being hinted at earlier last week? If that is the case then surely we should be looking down the barrel of another cold and snowy spell providing the NAO is still programmed to be negative (can anyone tell me what the latest NAO forecast is? Is it still programmed to be as negative as it was a few days ago). If that is the case I struggle to understand some of the negativity on here as I would think we would get a substantial snow event at some point?

Luke

[Thundery wintry showers]

Not quite. If the low was to stall out to the west of us, the result would eventually be mild southerlies.

[nick sussex]

How very true cuckoo, its charts like that that make me feel very sick indeed.

Hence the idea that if next weeks LP cant be further East, then let if go even further West of the UK, but then sink South, not just end up not knowing what to do next for about a week!

In fact, if it were to end up West, East, or south of us for about a week things could get very interesting, but NOT over us!

Feel that the last few GFS runs have just been lacking direction, 12z might be the run to inspire us a bit this afternoon.

Yes I agree with your last paragraph, further west or east but if it hangs around over the UK this will just modify the cold, however more importantly the further south the better.

Theres still alot of cold air over Europe, even with some moderation over the next few days any flow from there colliding with fronts moving into the UK should provide some snow. Its been so cold that even on the beaches near Bilbao they had a covering of snow, the Cote D'Azur also had snow yesterday, in fact around Biarritz a major surfing area had around 10 cms of snow lying!

So i think people looking for cold need to look east and se. At least if the pattern backs further west then as the next shortwave runs into the low near the UK, as this causes the low to pivot it could pull some colder air once again from the se bringing a decent chance of more snow before it turns less cold.

[Rollo]

I am putting my faith in the fact that the models cannot handle the current synoptics and I feel many more changes will occur before the final destination of our troublesome low is decided,maybe wishful thinking,we shall see.

[Thundery wintry showers]

I sense quite a lot of South East centric thinking- I'm really not sure whether looking east and SE would be good for cold/snow lovers in the long term, because the cold pool down there isn't that big, and if the low stalls out west (as many are hoping it does) it may only be a matter of time before milder, dull drizzly weather works its way up from the south and SW.

The low drifting away to the east would bring a greater chance of sustained wintry weather over the country as a whole delivered by northerly and north-westerly winds, while perhaps most ideal for cold/snow lovers taking Britain as a whole (though looking unlikely atm) is the low drifting to the SE giving NE winds.

Note that the possibility of this low hanging around the country is much the same situation as what happened from 20-23 December. The main difference is that the sun is stronger at this time of year and so established surface cold pools are harder to come by and maintain.

[snowray]

Hi,

Just expanding on what I said before does the outlook for next week in any way resemble that of March 2006? And if not then surely I would think that we could be in a pattern like that further down the line? Could we see another major "battleground" snow event before the winter is out? I am saying this because some tell me that the March 2006 event that resulted in substantial snowfall in my part of the world was also very marginal (with realitivly high uppers) like a lot of events like that are does anyone know what the models where predicting in the run up to that event? Because of that would it still be possible for the models to go back in our favour? Also is it true that the models have backed away from a -NAO too far west scenario that was being hinted at earlier last week? If that is the case then surely we should be looking down the barrel of another cold and snowy spell providing the NAO is still programmed to be negative (can anyone tell me what the latest NAO forecast is? Is it still programmed to be as negative as it was a few days ago). If that is the case I struggle to understand some of the negativity on here as I would think we would get a substantial snow event at some point?

Luke

Your not by any chance refering to late Feb- Early March 2005 are you? If so, yes, I'm thinking the same thing, could pan out very similar.

Edited February 12, 2010 by snowray

[chionomaniac]

My area of interest for the 12Z runs is to see if there is any suggestion of height rises between Iceland and Svalbard at around T+240. There doesn't need to be much just early indications, that's all.

[Duane S.]

As many have pointed out, what we don't want to see is the low meandering around willy-nilly. Any cold air will soon get modified and all but the highest places will probably have sleet or rain. What we want is it to drop down through the UK and get as far South as possible.

A good example of a low pressure system dropping down N to S and scooting out of the way sharpish was the 5th of March just last year. This dumped between 10 and 15cm of snow over parts of Dorset overnight and I gave up after an hour of trying to get out of Weymouth on the south coast to go to work as all routes were blocked. It warmed up to about 9 degrees the following day, something that is not likely to happen next week no matter what happens!

Edited February 12, 2010 by s4lancia

[Guest North Sea Snow Convection]

I sense quite a lot of South East centric thinking- I'm really not sure whether looking east and SE would be good for cold/snow lovers in the long term, because the cold pool down there isn't that big, and if the low stalls out west (as many are hoping it does) it may only be a matter of time before milder, dull drizzly weather works its way up from the south and SW.

The low drifting away to the east would bring a greater chance of sustained wintry weather over the country as a whole delivered by northerly and north-westerly winds, while perhaps most ideal for cold/snow lovers taking Britain as a whole (though looking unlikely atm) is the low drifting to the SE giving NE winds.

Note that the possibility of this low hanging around the country is much the same situation as what happened from 20-23 December. The main difference is that the sun is stronger at this time of year and so established surface cold pools are harder to come by and maintain.

Goodness me, what is it with all this anti SE'ism !? About time we cut out this regional divide nonsense.

It is, instead, purely and simply an analysis of the models and entirely to do with the point I made earlier and also the one that nick has given. And intended as a general Uk perspective. If I want to be happy about what happens in the SE then I know which thread to go to - and this sort of post is a good reminder why I have been spending so much time there!

The reality of it is that in the reliable time period we are relying on some continental airflow from the continent to engage with this low pressure system before it mixes the air out - and it is why there are predictions of snow from the METO earlish next week. If it really was such south-east centric thinking it wouldn't be something one would point out on the basis that this region isn't even covered by an advisory at this stage! So I am not sure what other motive would be left!?

Edited February 12, 2010 by North Sea Snow Convection

[snowray]

Yes I agree with your last paragraph, further west or east but if it hangs around over the UK this will just modify the cold, however more importantly the further south the better.

Theres still alot of cold air over Europe, even with some moderation over the next few days any flow from there colliding with fronts moving into the UK should provide some snow. Its been so cold that even on the beaches near Bilbao they had a covering of snow, the Cote D'Azur also had snow yesterday, in fact around Biarritz a major surfing area had around 10 cms of snow lying!

So i think people looking for cold need to look east and se. At least if the pattern backs further west then as the next shortwave runs into the low near the UK, as this causes the low to pivot it could pull some colder air once again from the se bringing a decent chance of more snow before it turns less cold.

Indeed Nick, as you say the key to all this is how far South the LP can sink.

Its all been a bit of a red herring to be honest looking North, since it was never going to shift far enough East for a decent Northerly/N Easterly blast to get going anyway.

Not just the coldest but also the nearest cold pool to the UK remains on the continent!

T60

This is actally quite a nice chart.

Cold pool holding on in the SE due to a small disturbance moving in from the low countries, and a small area of HP over Southern Scandi, can this build though I wonder?

LP further West!

Edited February 12, 2010 by snowray

[londonsnow]

i have to agree with tamara, it's fairly pointless having a go at the south east. a lot of people live here. its like bordeaux moaning about paris getting more attention. on the model front, well the 12z is out very soon, but this damn low wont be nailed for a few more runs i guess. all interesting though. LS

[MR EXTREMES]

yes looking at the 850s gfs if a more west dive was to happen its possible we getting better colder maybe -8s.

theres -12 and -8 west of scandi land.

and its swirling round anti clockwise.

Edited February 12, 2010 by badboy657

[snowray]

I sense quite a lot of South East centric thinking- I'm really not sure whether looking east and SE would be good for cold/snow lovers in the long term, because the cold pool down there isn't that big, and if the low stalls out west (as many are hoping it does) it may only be a matter of time before milder, dull drizzly weather works its way up from the south and SW.

The low drifting away to the east would bring a greater chance of sustained wintry weather over the country as a whole delivered by northerly and north-westerly winds, while perhaps most ideal for cold/snow lovers taking Britain as a whole (though looking unlikely atm) is the low drifting to the SE giving NE winds.

Note that the possibility of this low hanging around the country is much the same situation as what happened from 20-23 December. The main difference is that the sun is stronger at this time of year and so established surface cold pools are harder to come by and maintain.

Ah, but not if the Low sinks far enough South, thats the 1000000 dollar question, how far South can it get? This would draw the colder air over much of the country eventually, with snow on the Eastern boundary of the cold pool which could end up being anywhere not necessarily in the East/South East.

Edited February 12, 2010 by snowray

[MR EXTREMES]

west of scotland ireland would be spot on the could air in europe is being sucked round anti clockwise the 850pha temps show -8 to -12 air this must be what the meto have there eye on

114h the colder air is to our north is this going to sink i see no reason why not unless low stalls over the south of england.

and the core of the low pressure is indeed futher west its looking good but not 100% yet.

Edited February 12, 2010 by badboy657

[kold weather]

Everything abit further west on the 12z thus far and looks a very interesting run for Scotland whilst a rather wet run for the SE as the front gets stalled...still the broad evolution is pretty similar to the 06z GFS run, just that bit further west to start with.