Winter/Spring 2013 (Model Output Discussion)

Spindle

maw368 wrote: »

Fair point Spindle, I think a lot of people are going on about it being mild when November has been below average temps, I believe there was a load of months this year below average temps and the MO have forecast much of December to be below average temps. I am not sure about Ireland but much of this last week has seen significantly cold temps in much of England Wales and Scotland. According to the MO the MEAN LOW TEMP for much of the UK for the whole of winter never drops below freezing and this last week most have been below freezing with many being -4, -5 and even -7.

The MO described it as 90% probability of severe cold in their amber alert area with frost fog and snow, it was massively below the average winter temps never mind end of November temps. It has been cold, I believe it is back to this issue of comparing everything to the winter of 2010, unless it is as cold or as snowy for most of the UK then there is no winter because it is mild type attitude. I think Autumn has had inspiring temps for us cold lovers and I just hope it can continue but with snow.

Yeah I think 2010 spoiled a lot of people, they now want to have epic snowy winters. We are getting slightly colder months this year on average just not epic with snow.

Compared to the winters of the mid 90's to 00's we are getting more frosts recently, but I think people only remember what they want from the weather and also likewise only look for what they want.

BEASTERLY

Su Campu wrote: »

Where did I say I was 100% confident of anything? Models can of course be right, but they can be wrong too. They were hinting at a decent cold snowy setup here a few weeks ago but they were wrong. They could equally be wrong about the next few weeks, or they could be spot on. I didn't say they were useless, others said I did but look back and you won't find me saying that. All I asked was, leaving the models out of the scenario completely for a minute, what would be the reasons for someone's confidence in a cold spell and in dismissing what I am saying. If I had said yes, cold on the way, then I don't think anyone would be questioning me and I'd have a row of thanks on my posts.

Anyone remember the reception Sponge Bob got for going for a mild Christmas last year?

Were they wrong? They never really showed a decent snow spell. They showed a cool spell with Easterly/Northeasterly/Northerly winds with high pressure to the north. That transpired. The details might have been a bit off but in my opinion the got the theme right.

BLIZZARD7

Su Campu wrote: »

Right, so your reply was totally based on models then.

This is not purely a MODEL OUTPUT discussion thread, unless I missed the memo. It's a technical discussion, it just so happens it's turned into a MODEL rollercoaster!

Solar activity has been on the increase for the past couple of years. How would you explain last winter? Quoting winters hundreds of years ago is no guarantee of cold this winter!

Im not quite sure what your point is? No my ideas are not fully based on the models, I also consider all of the teleconnections that I know about- All of these are pointing towards a blocked outlook at the minute.

Solar activity has being on the increase yes but it is only increasing relative to its complete absence in 2008, activity levels in SC24 are way below what was expected and the highest activity levels are those expected by nasa, landscheidt had different ideas and these can be seen on the laymans sunspot count website. Either way we are in a very weak maximum if you can call it that. Lanscheidt has been more accurate so far and he speculated that the following cycles would be even less active.

And as I said, if the solar activity is indeed driving our weather then warm winters will occur, just less often than cold winters.

And to be honest I never guaranteed a cold winter, I just feel if is the most likely outcome given the great teleconnection and model outlooks.

The solar activity theory is just another thing to add to the list of factors that affect our weather.





Dan

Su Campu

catch.23 wrote: »

He got that reception because he was going for it over a week out, while at the same time anyone who was claiming cold weather a week out was being slated by you and others.

As it happened he was spot on, further proving that the models are pretty good even that far out.

I was slating them. Really? News to me. Maybe you take slating to mean someone giving a view different to what you want to hear but to me this is a discussion forum and therefore discussion should be two-way.

So, for the benefit of most here, and in an attempt to fit in get some thanks, we're in for a mother of a cold spell. You have been warned!

Deep Easterly

Spindle wrote: »

Yeah I think 2010 spoiled a lot of people, they now want to have epic snowy winters. We are getting slightly colder months this year on average just not epic with snow.

Compared to the winters of the mid 90's to 00's we are getting more frosts recently, but I think people only remember what they want from the weather and also likewise only look for what they want.

I personally believe that the current tabloid culture regarding winter is destroying peoples' perceptions of normal winter weather. Headlines that forecast almost apocalyptic weather ahead are becoming almost daily features. We have also seen a rise in pseudo meteorologists, especially from the UK and US, getting people all fired up on twitter and facebook about severe cold ahead, a severity which rarely materializes in the end. In isolation, fair enough, I doubt their would be little impact but the constant drone from these people is bound to have an affect on the populous.


As for 90's winters, I'd take them any day over what we have at present. They were far more changeable and just bigger and livelier than they are now. One thing I have learned over the last 2 or 3 years is that cold winters in Ireland are not really that interesting when it comes to actual weather. Cold for the sake of cold is nothing to celebrate or look forward too imo - especially in these times where many cannot afford enough fuel to keep warm on a consistent basis.

Roll on something better than this.

maquiladora

Deep Easterly wrote: »

Cold for the sake of cold is nothing to celebrate or look forward too imo - especially in these times where many cannot afford enough fuel to keep warm on a consistent basis.

Roll on something better than this.

I couldn't agree more with this. For me, the prospect of a proper cold spell is only good because of the potential for a serious snow event that comes along with that. But days and days of cold/ice with just a bit of snow showers? No thanks, thats a waste. I'd rather have mild, dry weather.

Speak Now

All i wish for this time of year is cold and dry, a post Christmas snowfall would be nice of course.

Mild and wet, that's summer weather

Anyway Models are still showing us the carrot in FI.

Stewart Rampling seems happy with the Technical.

As for a good easterly we're the last stop but first departure :mad:

But it's the only set up that delivers for the south east really (IMBY)

BEASTERLY

Su Campu wrote: »

All I asked was, leaving the models out of the scenario completely for a minute, what would be the reasons for someone's confidence in a cold spell and in dismissing what I am saying.

I am not dismissing what anybody is saying, you are. To answer your question about leaving the models aside, I have a couple of reasons to believe there is potential for a cold out break (not saying it will happen). Nobody id confident of a cold spell, just recognizing the is potential there!

The current state of the stratospheric vortex is very disorganized. In my opinion there is plenty of opportunity for blocking to take hold due to this, and indeed we have already seen some weak blocking to our north, stronger blocking elsewhere and high pressure being a regular feature over the artic. Lets compare this year to last year:

2012:


2011:


Another reason, the jet stream. Like the PV it as been very disorganised of late and weaker overall by a large margin! Plenty of meanders in it, all we need is one to dive south over the Atlantic and we could have a favourable block form. The current state of the jet stream allows for this scenario. Again, this year vs last year:

2012:


2011:


There's just two factors which I can see are conducive to cold reaching our shores. From what I've read here and elsewhere other much more knowledgeable observers are examining other factors, which in their opinion are favourable to a cold spell. I don't have much understanding of these processes so won't comment. Now can you put forward your reasons for backing a mild outcome? You said something about SST but can you expand?

ZX7R

Is anyone having trouble getting the climate prediction center,i was hoping to look at the nao but the site does not seem to be working?

John.Icy

For god sake, what's the harm in people reading models and making predictions off that, do find me any major weather organisation who don't have models as the first and foremost reference.

-Anyway, on topic. Nice GFS 12z, right the way out till +384. There's little chance of any charts past +120 actually coming off exactly as they are now, but the TREND remains and their is POTENTIAL for some cold weather down the line.

-Very encouraging ECM mean at +240 also. (Oz)

-Disrupted PV will be a help if any cold is going to come our way.

-If the outcome is a Scandi high and easterlies, could be quite a while before any really cold uppers make their way over here, very little serious cold to our east, will take a while to build.

-One thing about about the models that interests me also with the current trends; there is no serious cold in FI. Usually with phantom easterlies in FI that never happen, they have uppers of -12 or lower, serious cold. Currently, the trend shows nothing lower than -5/-6 uppers, a more believable outcome than if models were indicating an impending deep freeze. Not very scientific, but it's something I noticed.

pistolpetes11

Good post from Matt hugo on the netweather forum


Evening all...

Just bit of a one-off post from me in the model output thread and whilst this may not go down well, I want to air caution regarding the synoptic evolution, the reason being is experience and the amount of model divergence at medium and long term.

As GC pointed out there is GFS ENS mean support for the 12Z GFS Det model, however, lets get real, the synoptics at the end of the GFS Det run are akin to that of 63 for example, extreme blocking in all it's sense. Granted, you could equally argue the point that it could be right as much as it could be wrong because of the time frames involved, so I'll leave that "chicken and the egg" scenario for discussion.

However, I've been on shift for 6 days now and I have been struggling to forecast synoptic changes at days 5 and 6, let alone out to next week and beyond. I have quite publicaly discussed the potential changes long term thanks to stratospheric conditions, but as ever the information is just that, information on a forecast chart. Until it actually happens it is nothing more than a 'prediction', which isn't a certainty.

The amount of spread evident within the 12Z GFS ENS longer term highlights the model uncertainties over the synoptic evolution. As is often the case the models, for the UK, struggle so much in this kind of synoptic pattern. Throw up a zonal pattern, like last December, and the ensembles never vary very much as it is such an 'easy' pattern to forecast. The 'behind closed doors' ECMWF ENS information also throws up some major divergences in synoptic evolution towards and beyond T+300hrs, to the point where the 51 ECMWF ensemble members, of late, have been split 5 or 6 different ways.

I recommend caution regarding the up coming synoptic pattern. The stratospheric conditions are indeed conducive to blocking patterns and clearly the longer term stratospheric conditions may well enhance that risk, but this isn't the be all and end all. There's a lot more to forecasting and these E or NE'ly solutions long term are still very much in the balance for now until far more model consistency in particular develops.

One thing's for sure, despite the uncertainties and potential outcomes, it makes for a far more interesting model analysis than for example the zonal dross of last December which anyone could forecast with their eyes closed!.

Let's see what happens.

Cheers, Matt

whitebriar

Hmmmm.... Do I smell snow?

Not sure I do with surface pressure over Ireland in todays 12z gfs at circa 1030mb when there's a scandi high.
Its so rare to get that blooming hp cell to position itself rightly.

I'd caution snow lovers secondly from getting too excited about easterlies this early in play,pure cold this early does not settle in western europe,the benelux countries for example.
It has to be fed in there from Siberia and that's by the scenic route.
The M1 to Ireland at this time of the year as we saw for cold in late 2010 is via scandinavia not south of it, thats usually a january,feb,march route when cold has severly established in eastern europe.

The synoptics are fascinating but unclear.It takes very little change now to majorly alter 5 days time never mind 10 days time.Look for 850 temps of at least -7c from the east or north east entering Ireland.
They don't have to be as cold up at 5000ft from that direction or the east to bring snow but the colder the better as you need them sub -7 up there to bring convection.You also need surface pressure at 1025 or lower ideally,as in simple terms,super cold air can cause shallow lows to embed in the flow enhancing shower activity.
They need to be colder from the northwest by the way as there's too much maratime mixing from that side.


My current thoughts are,I just don't know.If super modeling can't tell us it will be super mild or super cold in a week,how can I? Fascinating mix of model solutions though.
But do ya know,I've a feeling somethings brewing,a feeling in me briars

whitebriar

Weathering wrote: »

Just when I thought I couldn't get anymore confused as to what is going to happen,that post from netweather has dumbfounded me more ha

Just FYI.
Matt Hugo,is a forecaster working for a well respected private professional forecasting service.
As such he has access to heaps of data us posters here do not have including ecm extra analysis and of course access to the opinion of other professionals including the Uk met office.

That means he's a realist,even though he likes snow.
Read his thoughts in that vein.

If he or for example Ian Ferguson on Netweather become more certain,then it might be time to get excited.

whitebriar

Ach,its always uncertain with cold really as its not our climate type so it's unusual.

I mean,rainy weather is rain,whether it comes from south,west,south,southeast,its so boring,we don't notice how uncertain it is and its often uncertain.

The weather type most look for in winter has added frustration as any old synoptics can bring rain,but snow need a cocktail of a whole lot of things,which in chaos theory are well hard to get.

Did I tell you I've a feeling in me briars though ( just by the way the athmosphere is behaving already,but hey who knows?)

Spindle

maquiladora wrote: »

I couldn't agree more with this. For me, the prospect of a proper cold spell is only good because of the potential for a serious snow event that comes along with that. But days and days of cold/ice with just a bit of snow showers? No thanks, thats a waste. I'd rather have mild, dry weather.

Yeah give me a good cold/warm battle ground type situation that we used get in the 80s early 90s, was always good for epic snow that used too last a day or two, then the Atlantic would win returning us to the mild with a storm on the horizon. (Although these are always better for us in the Munster)

These events were always the Ninja snow events, leading to a day off school.

Deep Easterly

whitebriar wrote: »

Just FYI.
Matt Hugo,is a forecaster working for a well respected private professional forecasting service.

Then he should have more sense. Any professional Meteorologist of any worth would not even consider basing a forecast outside of the 5 to 7 day range.

Welcome back BB, or should I say, 'WB'.

Su Campu

BEASTERLY wrote: »

I am not dismissing what anybody is saying, you are. To answer your question about leaving the models aside, I have a couple of reasons to believe there is potential for a cold out break (not saying it will happen). Nobody id confident of a cold spell, just recognizing the is potential there!

The current state of the stratospheric vortex is very disorganized. In my opinion there is plenty of opportunity for blocking to take hold due to this, and indeed we have already seen some weak blocking to our north, stronger blocking elsewhere and high pressure being a regular feature over the artic. Lets compare this year to last year:


Another reason, the jet stream. Like the PV it as been very disorganised of late and weaker overall by a large margin! Plenty of meanders in it, all we need is one to dive south over the Atlantic and we could have a favourable block form. The current state of the jet stream allows for this scenario. Again, this year vs last year:

There's just two factors which I can see are conducive to cold reaching our shores. From what I've read here and elsewhere other much more knowledgeable observers are examining other factors, which in their opinion are favourable to a cold spell. I don't have much understanding of these processes so won't comment. Now can you put forward your reasons for backing a mild outcome? You said something about SST but can you expand?

I have already put forward my reasons. Decreasing warm SST anomalies in northern waters will, through reduced height anomalies, mitigate the formation of blocks in that region. Arctic sea ice has reformed, therefore the scope for influence from that minimum is eroding week by week.

Regarding the polar vortex, looking at 500 hPa charts is not wise when looking long-term. The key is in the stratosphere (10-70 hPa), and although there is currently a semi-split, this is closing up and the polar vortex will be restrengthening in the near future. This then translates to a lack of support for tropospheric blocking further along the line.

The jet stream is not a driver, it is linked to the polar vortex, so when one the vortex strengthens then the jet stream will follow suit, which I think will happen. It's like saying the NAO or AO will cause this or that type of weather - they're only indicators of what the real drivers are doing.

Anyway, that's what I think. I'm allowed my opinion just as much as the next man, despite the fact that it goes against the common wish. Maybe it'll turn out to be completely wrong and the models will be right, I don't really care. I'm not making a living at this and therefore, unlike most of the pros quoted on here, my pocket won't be depending on giving people what they want to hear.

Weathering

I see my latest post was removed?? Whatever for. Freedom of speech is dying by the day.
Anywho onwards and upwards http://www.netweather.tv/index.cgi?action=monthly;sess=

sully2010

@ XX XXXXX I'm just a follower on here but I feel compelled to post. I consistently find your posts to be negative, condescending and Mr. know it all. Do me a favour CHEER UP ITS CHRISTMAS IN A FEW WEEKS!!! Flip sake



MOD NOTE
THE ONLY REASON THE LAST TWO POST'S HAVE BEEN LEFT HERE IS TO LET PEOPLE KNOW THERE IS NOW WARNINGS AND INFRACTIONS BEING HANDED OUT ,

ONCE AGAIN KEEP IT ON TOPIC

pistolpetes11

If people actually want to learn about the charts and other contributory factors to our weather , there has been some excellent posts for and against the cold weather by Su Campu , Beasterly, Blizzard and a few others lately.

For me this is where you will pick up an awful lot of knowledge through these exchanges of opinion on what may or may not happen and there reasoning for thinking so.

Su Campu

Weathering wrote: »

I see my latest post was removed?? Whatever for. Freedom of speech is dying by the day.
Anywho onwards and upwards http://www.netweather.tv/index.cgi?action=monthly;sess=

I don't get it Weathering, the link you've posted is saying pretty much the same thing I'm saying, yet you somehow take exception to me saying it! :rolleyes:

That forecast would go along the lines of some mid-Atlantic, Azores or Bartlett highs, with the low pressures sliding down the North Sea. Matt Hugo's earlier post similarly doesn't post a very cold picture for the foreseeable either. Like it or lump it that would seem to be the way things are lining up.

pistolpetes11

Su Campu wrote: »

I don't get it Weathering, the link you've posted is saying pretty much the same thing I'm saying, yet you somehow take exception to me saying it! :rolleyes:

That forecast would go along the lines of some mid-Atlantic, Azores or Bartlett highs, with the low pressures sliding down the North Sea. Matt Hugo's earlier post similarly doesn't post a very cold picture for the foreseeable either. Like it or lump it that would seem to be the way things are lining up.

Just on Matt , just updated on his twitter feed about the ECM ENS clusters

Matthew Hugo ‏@MattHugo81
ECM ENS clusters are grouped with 39 out of 51 members signalling a block to the N or NE beyond 216/240hrs. Other 12 have high over the UK.

Weathering

Su Campu wrote: »

I don't get it Weathering, the link you've posted is saying pretty much the same thing I'm saying, yet you somehow take exception to me saying it! :rolleyes:

That forecast would go along the lines of some mid-Atlantic, Azores or Bartlett highs, with the low pressures sliding down the North Sea. Matt Hugo's earlier post similarly doesn't post a very cold picture for the foreseeable either. Like it or lump it that would seem to be the way things are lining up.

I never said anything to back u up su so don't put words in my mouth
Not my fault u can't speak without being a ignorant. I supplied a link for people top read not to inflate your head,your twisted


MOD NOTE
POSTER BANNED FOR THE ABOVE

pistolpetes11

Weathering wrote: »

Moderator obviously biased towards Su, deleting my post directed at her and quoting hers against mine

BANNED FOR 3 DAYS FOR PERSONAL ABUSE (the post above) , BACKSEAT MODERATION

Su Campu

pistolpetes11 wrote: »

Just on Matt , just updated on his twitter feed about the ECM ENS clusters

Matthew Hugo ‏@MattHugo81
ECM ENS clusters are grouped with 39 out of 51 members signalling a block to the N or NE beyond 216/240hrs. Other 12 have high over the UK.

That would be a nudge in the right direction, but with a strengthening PV by then it may be short-lived.

Anyway, that's all I'm saying in this thread.

whitebriar

Deep Easterly wrote: »

Then he should have more sense. Any professional Meteorologist of any worth would not even consider basing a forecast outside of the 5 to 7 day range.

Welcome back BB, or should I say, 'WB'.

Hum thanks,I think

He's not forecasting I think,he's just musing out loud like the rest of us.

Mind you doesn't the mighty Evelyn put up 10 day ecm's on Rte all the time often with it not happening...there was a run on kerosene in Arklow last winter one time when she did that

BEASTERLY

Su Campu wrote: »

That would be a nudge in the right direction, but with a strengthening PV by then it may be short-lived.

Anyway, that's all I'm saying in this thread.

Thanks for the last reply, very informative. Why do you believe the strat PV is going to be cranking up @ day 9 or 10? Surely model output for the strat at that timeframe is subject to the exact same FI caveats? And if the models go for blocking while also progging a strengthening strat PV, what does that tell us about the strength of correlation between stratospheric vs tropospheric synoptics?

hatrickpatrick

Very quick question: How many hours ahead does a model have to be in order to be classed as "fantasy island"?

pistolpetes11

hatrickpatrick wrote: »

Very quick question: How many hours ahead does a model have to be in order to be classed as "fantasy island"?

Anything after 96 hours , 3-4 days is the usual reliable time period

Deep Easterly

Time for some light relief. C'mon everyone, sing a long!

https://www.youtube.com/watch?v=FCARADb9asE