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Posted
  • Location: East Anglia
  • Location: East Anglia

Your right it is a lovely run and potentially snowy for some areas but because it does not

have any support for this evolution from the other two models I think its a case of more

runs needed.

Certainly some potential out there, but as you say plenty more runs needed, I don't doubt we will see HP take control over the UK but a long way to go before we see how that sets up.

To the member who suggested that the models are having a harder time of it this year, FI closer etc, way off I'm afraid, just wishful thinking that the models are struggling with some of the synoptics we have seen this winter, the models are not struggling any more than usual.

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Posted
  • Location: Nottingham
  • Location: Nottingham

It has been clear for the whole winter that model agreement has been a real issue even at 96 hours -- infact even closer at times. I am not sure how anyone can really say otherwise.

Edited by kev238
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Posted
  • Location: Blackburn - 180m asl
  • Location: Blackburn - 180m asl

This may just be too far ahead but I think people should take a look at the GFS 12Z from Tues all the way to Fri if it comes of we could end up with some quiete high snow totals in Central England-North East England-Southern Scotland. I hope this run comes off and the GFS sticks with it will definetaly be winters last attack.

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Posted
  • Location: portsmouth uk
  • Weather Preferences: extremes
  • Location: portsmouth uk

Your right it is a lovely run and potentially snowy for some areas but because it does not

have any support for this evolution from the other two models I think its a case of more

runs needed.

i do agree for once ive just flicked through every model around the similar time frame and theres no question it wants to bring the heights into play.

its either going to be dry cool and sunny but it all depends on how this sets up i think theres every chance of settled cool frosty in the north and cold easterly wind with some snow showers in the south if not dry aswell with some decent frosts in march.

but there is good agreement from nearly all models what it does show there is no mild spring weather in the near to medium term.

so after all my ranting last week just goes to show the weather will do what it wants in the near term we have some rather windy weather on the way intresting stuff.:whistling:

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Posted
  • Location: Pontypridd, Wales 240m asl
  • Location: Pontypridd, Wales 240m asl

It has been clear for the whole winter that model agreement has been a real issue even at 96 hours -- infact even closer at times. I am not sure how anyone can really say otherwise.

I totally agree with you - the models have a really tough time with these blocking scenarios

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Posted
  • Location: East Anglia
  • Location: East Anglia

It has been clear for the whole winter that model agreement has been a real issue even at 96 hours -- infact even closer at times. I am not sure how anyone can really say otherwise.

Maybe by somebody who has watched the models in all seasons for the last five years? I can assure you that the models have performed no worse this winter than last. Sometimes the models get a good grip out to the mid range at other times less so. Remember the models simulate climate they do not get programmed with past data, they won’t change next year because of how this winter has panned out. Maybe it’s just because this winter has been different and therefore the models have been scrutinised more than over recent winters that it appears they are struggling more than at other times.

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Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire

I think the models have indeed performed similarly to most winters, but because of the anomalous prevalence of blocking around the British Isles, any errors in the models have had much larger implications than usual. For example, in a mobile Atlantic regime with fronts moving from west to east at intervals, if the models have a low pressure a few hundred miles too far north, south or east, it might mean that the timing of the associated fronts is a bit different, or that some areas get heavier rain relative to others than expected, but it makes no difference to the overall pattern. In contrast in a blocked setup a difference of a few hundred miles can mean the difference between mild southerlies and cold northerlies, or result in milder air getting as far north as the Scottish Lowlands instead of grazing the south coast of England.

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Posted
  • Location: East Anglia
  • Location: East Anglia

I think the models have indeed performed similarly to most winters, but because of the anomalous prevalence of blocking around the British Isles, any errors in the models have had much larger implications than usual. For example, in a mobile Atlantic regime with fronts moving from west to east at intervals, if the models have a low pressure a few hundred miles too far north, south or east, it might mean that the timing of the associated fronts is a bit different, or that some areas get heavier rain relative to others than expected, but it makes no difference to the overall pattern. In contrast in a blocked setup a difference of a few hundred miles can mean the difference between mild southerlies and cold northerlies.

Yep I think that’s a fair point. I guess as well that for me for the post 72hrs period I'm really looking for the general pattern rather than specifics in terms of who gets snow, rain etc. So if I see let’s say for instance, the type of pattern being projected for the up and coming post mid week spell, then all the models are hinting at a blocking pattern, on some the HP is of the dartboard type centered more or less over the UK, in others it’s more elongated, pulling in air from the east with tighter isobars and so on. For me that’s good model consensus, HP will dominate the UK weather scene, the detail will come in time, pretty standard model behaviour in my book I don’t expect the models to agree on detail for five days hence.

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Posted
  • Location: Cambourne Cambridge 70M ASL
  • Weather Preferences: Blizzards,Hot Thundery nights.
  • Location: Cambourne Cambridge 70M ASL

I think the models have indeed performed similarly to most winters, but because of the anomalous prevalence of blocking around the British Isles, any errors in the models have had much larger implications than usual. For example, in a mobile Atlantic regime with fronts moving from west to east at intervals, if the models have a low pressure a few hundred miles too far north, south or east, it might mean that the timing of the associated fronts is a bit different, or that some areas get heavier rain relative to others than expected, but it makes no difference to the overall pattern. In contrast in a blocked setup a difference of a few hundred miles can mean the difference between mild southerlies and cold northerlies, or result in milder air getting as far north as the Scottish Lowlands instead of grazing the south coast of England.

Fantastic post ,explained very well, and yes with models forecasting atlantic zonal patterns,its just a case of when will it rain not if it will rain.But with blocking the differences from slight changes are huge and more likely to be remembered when snow is forecast and then downgrades towards the reliable time frame.

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Posted
  • Location: Aldborough, North Norfolk
  • Location: Aldborough, North Norfolk

I think the models have indeed performed similarly to most winters, but because of the anomalous prevalence of blocking around the British Isles, any errors in the models have had much larger implications than usual. For example, in a mobile Atlantic regime with fronts moving from west to east at intervals, if the models have a low pressure a few hundred miles too far north, south or east, it might mean that the timing of the associated fronts is a bit different, or that some areas get heavier rain relative to others than expected, but it makes no difference to the overall pattern. In contrast in a blocked setup a difference of a few hundred miles can mean the difference between mild southerlies and cold northerlies, or result in milder air getting as far north as the Scottish Lowlands instead of grazing the south coast of England.

Excellent point.

Now looking slightly further ahead that T96, looks like an Easterly, but not a Beasterly next week. At about T168, we have a good easterly, BUT, now the north sea is cooler, we have less convection. Early in teh winter, too warm, therefore rain unless a big easterly, later, too cold unless a slacker flow, can't win

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Posted
  • Location: Madrid, Spain (Formerly Telford)
  • Location: Madrid, Spain (Formerly Telford)

The South West would finally get given a chance for a major Snow Event if the 18z came off so for this reason i hope it does for the poor snow deprived West Country folk.

Looks pretty likely high pressure may well arrive next week in the end though i can unfortunately see it ending up, after a brief easterly, drawing north westerly winds with anticyclonic gloom though i may be wrong.

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Posted
  • Location: Weymouth, Dorset
  • Location: Weymouth, Dorset

I think the models have indeed performed similarly to most winters, but because of the anomalous prevalence of blocking around the British Isles, any errors in the models have had much larger implications than usual. For example, in a mobile Atlantic regime with fronts moving from west to east at intervals, if the models have a low pressure a few hundred miles too far north, south or east, it might mean that the timing of the associated fronts is a bit different, or that some areas get heavier rain relative to others than expected, but it makes no difference to the overall pattern. In contrast in a blocked setup a difference of a few hundred miles can mean the difference between mild southerlies and cold northerlies, or result in milder air getting as far north as the Scottish Lowlands instead of grazing the south coast of England.

I agree with other comments, a brilliantly concise and accurate summary there TWS. :(

Certainly appears to be be model apathy at the moment going on here. Probably about the 1000th time it has been said in the past month but it is testiment to what a great winter we have had that chart runs like the ECM 12z, tonight's GFS 18z and the GEFS ensembles of late that it hardly raises an eyebrow! Back in the day there would have been a server meltdown as everybody clamoured onboard to see the latest offerings and post their musings.

Back to the weekend system and the more I look at it the more dangerous and horrendous a storm this looks. Thankfully (almost certainly) not for us here in the UK but be in no doubt that death and destruction is going to occur over parts of mainland Europe from Spain to Denmark come Sunday. Not good... Although as Ian F (I think it was) said earlier, one saving grace will be the lack of leaves on the trees.

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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire

Certainly appears to be be model apathy at the moment going on here. Probably about the 1000th time it has been said in the past month but it is testiment to what a great winter we have had that chart runs like the ECM 12z, tonight's GFS 18z and the GEFS ensembles of late that it hardly raises an eyebrow! Back in the day there would have been a server meltdown as everybody clamoured onboard to see the latest offerings and post their musings.

Whilst I agree that this has been a great Winter or possibly even exceptional given our 'warmer' climate, I think one of the other reasons for not many on here getting excited is because many a time recently the models have shown dream synoptics at fairly short range only for them to be downgraded as the time comes. As others have said, lots more runs needed before we can get excited.

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Posted
  • Location: Heswall, Wirral
  • Weather Preferences: Summer: warm, humid, thundery. Winter: mild, stormy, some snow.
  • Location: Heswall, Wirral

In my opinion I cant help but be sceptical of an easterly being shown at 168 hours or so. I think the tendency is for it to be quite a strong easterly, but if the AO is planning on going to neutral around that time, I just cannot foresee a strong easterly. The NAO stays rather negative which is indicative of height rises to the north, but to me the easterly has little chance of ocurring.

The northerly has a chance but how long will it stay around is the question if it does occur.

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Posted
  • Location: Bexhill-on-Sea, East Sussex
  • Weather Preferences: Winter Snow, extreme weather, mainly sunny mild summers though.
  • Location: Bexhill-on-Sea, East Sussex

Whilst I agree that this has been a great Winter or possibly even exceptional given our 'warmer' climate, I think one of the other reasons for not many on here getting excited is because many a time recently the models have shown dream synoptics at fairly short range only for them to be downgraded as the time comes. As others have said, lots more runs needed before we can get excited.

Quite true, but maybe more to the point is that many areas are fortunate enough to get reasonable snowfall amounts in marginal set ups, where as highly populated areas like London almost always miss out. So even 50 miles can make a massive difference to areas like West Essex, North Kent, Surrey, Hamps, and Greater London of course. East Kent has its own mini climate, and areas directly just North of London generally fare rather well in comparison like the Chilterns.

So at this stage yes, a certain amount of model fatique I feel for those who have generally missed out, and for people in the rest of the country that have seen decent snow in Feb, well maybe they are now looking forward to more springlike weather or have just become blase' about it all.

Quite agree with TWS, was thinking the same thing, and it was extremely well put. At the end of the day we must remember that these are global models, so while we are looking mainly at IMBY, IE western Europe, there will be paterns and blocking all over the globe that are being constantly calculated. Fot a Londoner, a cold Easterly will be the golden nugget in Winter months for snow, a NEly, or NNEly or SEly might not be so good. So we pay much more attention and notice the sometimes small and suble changes in wind direction. But if the Atlantic is driving the weather, week in, week out, as often happens in Winter, who is realy going to notice if we end up with a Wly, SWly, SSWly, and everything in between.

Certainly the charts are looking cold into March, and there could be snow around again, maybe for many, after all, some of these charts look great. But for some areas things will have to be just right, as ever, so I'm not going to get too carried away just yet.

Edited by snowray
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Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire

This showing 144 hours away and only a handful of posts? As s4lancia says, we really must have had an exceptional winter if people almost expect to see chaarts like this now!

h850t850eu.png

If that chart was to come off it would be awesome. However, at 144 hours it's still FI. Certainly something to keep an eye on, though.

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Posted
  • Location: North Yorks, prev West Essex
  • Location: North Yorks, prev West Essex

I suspect [and me included] most are suffering from "Winter Fatigue". Yes we have had a winter but some are now looking forward to Spring. Or are expecting far too much now!!

I too am worried about the potential rain for Sunday. My garden has a swimming pool in it, which I may add I did NOT order. I live quite high for my area so flooding will not be an issue for me, but plenty of my friends may have after Sunday.

The BBC forecast at 6.30 looked rather nasty, let's hope for a downgrade which even includes France! [joke] :(

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Posted
  • Location: Bexhill-on-Sea, East Sussex
  • Weather Preferences: Winter Snow, extreme weather, mainly sunny mild summers though.
  • Location: Bexhill-on-Sea, East Sussex

If that chart was to come off it would be awesome. However, at 144 hours it's still FI. Certainly something to keep an eye on, though.

It could still go all wrong at T48, as we all know too well. Even in this most exceptional of Winters, not many of the realy juicy charts such as this one have come to fruition from this sort of time frame, most having been watered down somewhat. Watered down synoptics will not be good enough as we go into March I'm afraid.

Maybe we are due for an upgrade for a change? :(:(

Edited by snowray
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Posted
  • Location: Rushden, East Northamptonshire
  • Location: Rushden, East Northamptonshire

As we head into March, these situations tend to have low dewpoints - where you can easily get snow despite air temperatures well above freezing. But any real settling is limited to overnight and morning periods generally in England. The minute the sun pokes out, any lying snow of a thickness less than about 3 inches will clear off in a jiffy. The snow overnight Thursday/Friday last week made a good attempt to hold out, and it was getting topped up until Tuesday. In sheltered areas there was 5 inches, in areas exposed to not even sun, a transient cover of an inch or nowt. But the uppers weren't terribly cold. Only cold cloudly conditions can maintain snow cover on low ground in England as we get into March, because the thaw by day will be rapid. Great to see -10C 850s possibly, but these will still see daytime maximas of +3 or a bit more. You'd need to have quite a lot of snow on the ground not to see it reduced to nill during daytime.

Seen some surprises before a la Sunday/Monday. I remember something like this starting off as a rain event but went on to give a foot of wet snow in the early 90s in North Yorks. The BBC forecasts just said heavy rain, and outside of the Radio Cleveland area it was never mentioned in the outside world. Nominally it couldn't happen until now because the SSTs were too high. So I would suggest a swift bit of nowcasting on Sunday to see whether something might be on the cards. The Met Office seem to have thought so on their clicky clicky forecast weather bits for the past 3 days, but haven't put out any warnings, despite have the dubious heavy snow cloud directly over this southern part of the East Midlands.

I had a client in from Vienna yesterday, it was even warmer there - upto 13C. So The cold air in this easterly needs to make quite a sudden impact.

Edited by mackerel sky
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Posted
  • Location: Liphook
  • Location: Liphook

The set-up between 96-144hrs is very complex with regards to what exactly could happen. The broad trend is for a slow rise of pressure to our north however how the low system evovles will make the difference between getting a cold easterly or not.

Still the evolution the GFS and to some extent the ECM, though on a much greater timeframe, both would lead to a possible big snow event, a upper low sinks southwards and nearly cuts off, when this happens the whole thing will become very slow moving and thats when we see an increased snow threat.

However we are far too far out to need to worry about that. For now there is a strong trend towards higher pressure near the UK, however any half decent upper block is going to deflect the jet southwards, esp given its already on a broadly southerly track compared to normal...and a very strong signal for a below average first half to March...

Glad to see my -ve NAO call getting closer to frution!

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Posted
  • Location: Llantwit Fardre, Pontypridd
  • Location: Llantwit Fardre, Pontypridd

Maybe a stupid question so mods feel free to move or delete but

why dont the models take into account historical data i.e why dont they learn from this year to be better next year?

Seems common sense to me but some posts i read earlier seem to say that this is disregarded is that really the case as if so the models are never going to be really accurate as they are relying on human programming rather than real world data and not tuning themselves to what is reallly going on.

Not a big fan of A.I. but surely if a framework for modelling is put in place and its fed with more and more data to learn from it should become more accurate.

If someone can answer this i would be very interested in the reply :(

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

no model has any prior statistics fed into it-the solving of the complex thermodynamics of the atmosphere is what they are about-fluid dynamics to be precise. Again all models are 'tweaked' for improving their output for things like how it deals with rain, topography but there is never any climatology fed into any model. Raw data from all over the world, from the surface to the hgih atmosphere, for the weather as it is.

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Posted
  • Location: Evesham/ Tewkesbury
  • Weather Preferences: Enjoy the weather, you can't take it with you 😎
  • Location: Evesham/ Tewkesbury

The two main players both ecm and gfs are both after a cold spell next week of course Scotland wont see any difference from recent months, but both models are uniquely different! :blink:

post-6830-12672590770817_thumb.png

post-6830-12672592499717_thumb.png

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Posted
  • Location: East Anglia
  • Location: East Anglia

Maybe a stupid question so mods feel free to move or delete but

why dont the models take into account historical data i.e why dont they learn from this year to be better next year?

Seems common sense to me but some posts i read earlier seem to say that this is disregarded is that really the case as if so the models are never going to be really accurate as they are relying on human programming rather than real world data and not tuning themselves to what is reallly going on.

Not a big fan of A.I. but surely if a framework for modelling is put in place and its fed with more and more data to learn from it should become more accurate.

If someone can answer this i would be very interested in the reply :blink:

The models work as John says, but let’s for a minute work them in the way you suggest. Take one factor, this year has seen the jet run on a very southerly track, it’s been a real feature and an important factor in our weather. Let’s tell our model that because of how the jet has behaved this winter then come next year keep modelling the jet way to the south. What would then happen if the jet doesn’t stay on a similar track next winter, suppose its 500 miles further north on average, then the models would be a disaster, useless in fact. The models work as john says, they have been no worse this year than last, because they work in the way that they do, they are if you like apolitical, and above year in year out fluctuations in climate, they have no bias towards a warmer or cooler world. If next winter was to usher in the start of a new ice age, then they would model that on the science of how the climate works, they would not know how to do otherwise.

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