John S2
16 November 2013 15:30:01

Originally Posted by: Matty H 

Originally Posted by: NickR 


Without wanting to bang on about it, seasonal forecasting and its associated threads are a waste of time. As I said the other day it's like commenting on when you think you might next catch a cold, or win a tenner on the lottery. There's no tool for predicting it, just several tools that attempt to, but can't possibly do so as we have no capability.


This view is quite simply wrong. There are numerous indicators and methods for predicting whether a coming winter will be generally milder or colder than average in the region of the British Isles. Quite a number of these have been shown to be better than tossing a coin.

Matty H
16 November 2013 15:33:55
Originally Posted by: John S2 

Originally Posted by: Matty H 

Originally Posted by: NickR 


Without wanting to bang on about it, seasonal forecasting and its associated threads are a waste of time. As I said the other day it's like commenting on when you think you might next catch a cold, or win a tenner on the lottery. There's no tool for predicting it, just several tools that attempt to, but can't possibly do so as we have no capability.


This view is quite simply wrong. There are numerous indicators and methods for predicting whether a coming winter will be generally milder or colder than average in the region of the British Isles. Quite a number of these have been shown to be better than tossing a coin.



I completely disagree. There isn't a single tool out there that is statistically more accurate at predicting an entire season than any other, and they're all pretty rubbish at it. That's a fact or we'd have a decent idea. We don't have a clue. Even the experts completely rubbish seasonal forecasts. Fergusson did exactly that on Twatter this week if you have a peek.
John S2
16 November 2013 15:45:14

Originally Posted by: Matty H 

Originally Posted by: John S2 


Originally Posted by: Matty H 

Originally Posted by: NickR 


Without wanting to bang on about it, seasonal forecasting and its associated threads are a waste of time. As I said the other day it's like commenting on when you think you might next catch a cold, or win a tenner on the lottery. There's no tool for predicting it, just several tools that attempt to, but can't possibly do so as we have no capability.


This view is quite simply wrong. There are numerous indicators and methods for predicting whether a coming winter will be generally milder or colder than average in the region of the British Isles. Quite a number of these have been shown to be better than tossing a coin.




There isn't a single tool out there that is statistically more accurate at predicting an entire season than any other,


This is incorrect. Repeating it doesn't make it come true. Statistical evidence has been produced in this thread by different posters regarding some of the methods that have merit. 

nouska
16 November 2013 15:53:43
From the tools available and reading about weather drivers, the milder, zonal outlook in the models is understandable - it is what known physics suggests. It might give a rough idea for the large continental land masses - for the UK, pretty hopeless as the skill level masks on some of the output shows.

Add in the the possible circulatory effects of Arctic ice loss and low solar cycle; all bets are off with regard to what is in store this winter.

In the words of Gooner and JFF - I think winter '95/'96 might be something to look at as an analogue.
Matty H
16 November 2013 16:04:26
Originally Posted by: John S2 

Originally Posted by: Matty H 

Originally Posted by: John S2 


Originally Posted by: Matty H 

Originally Posted by: NickR 


Without wanting to bang on about it, seasonal forecasting and its associated threads are a waste of time. As I said the other day it's like commenting on when you think you might next catch a cold, or win a tenner on the lottery. There's no tool for predicting it, just several tools that attempt to, but can't possibly do so as we have no capability.


This view is quite simply wrong. There are numerous indicators and methods for predicting whether a coming winter will be generally milder or colder than average in the region of the British Isles. Quite a number of these have been shown to be better than tossing a coin.




There isn't a single tool out there that is statistically more accurate at predicting an entire season than any other,


This is incorrect. Repeating it doesn't make it come true. Statistical evidence has been produced in this thread by different posters regarding some of the methods that have merit. 



What statistics? Not one person has linked statistics that prove any model has a handle on seasonal forecast accuracy. Repeating it doesn't make it correct.
Matty H
16 November 2013 16:06:47
Originally Posted by: nouska 

From the tools available and reading about weather drivers, the milder, zonal outlook in the models is understandable - it is what known physics suggests. It might give a rough idea for the large continental land masses - for the UK, pretty hopeless as the skill level masks on some of the output shows.

Add in the the possible circulatory effects of Arctic ice loss and low solar cycle; all bets are off with regard to what is in store this winter.

In the words of Gooner and JFF - I think winter '95/'96 might be something to look at as an analogue.



Spot on. Seasonal forecast accuracy due to model ability is a total fallacy. It's easy to go for the most likely outcome. That doesn't make it smart.

Bottom line is no one, including the experts have a clue what will happen and they'll admit so. That tells you all you need to know. Anyone who believes any model has a decent hang on it is only kidding themselves. 😂
springsunshine
16 November 2013 16:35:43

Originally Posted by: Matty H 

Originally Posted by: nouska 

From the tools available and reading about weather drivers, the milder, zonal outlook in the models is understandable - it is what known physics suggests. It might give a rough idea for the large continental land masses - for the UK, pretty hopeless as the skill level masks on some of the output shows.

Add in the the possible circulatory effects of Arctic ice loss and low solar cycle; all bets are off with regard to what is in store this winter.

In the words of Gooner and JFF - I think winter '95/'96 might be something to look at as an analogue.



Spot on. Seasonal forecast accuracy due to model ability is a total fallacy. It's easy to go for the most likely outcome. That doesn't make it smart.

Bottom line is no one, including the experts have a clue what will happen and they'll admit so. That tells you all you need to know. Anyone who believes any model has a decent hang on it is only kidding themselves. LOL


Seasonal forecasts are pure guesswork,impossible to forecast and all these models you can read whatever you like into them.Its akin to predicding the lottery numbers.I really can`t believe this thread was started early september and is as long as it is.Will the summer 2014 prospects thread start in early march??

Gooner
16 November 2013 16:41:50

Originally Posted by: springsunshine 


Originally Posted by: Matty H 

Originally Posted by: nouska 

From the tools available and reading about weather drivers, the milder, zonal outlook in the models is understandable - it is what known physics suggests. It might give a rough idea for the large continental land masses - for the UK, pretty hopeless as the skill level masks on some of the output shows.

Add in the the possible circulatory effects of Arctic ice loss and low solar cycle; all bets are off with regard to what is in store this winter.

In the words of Gooner and JFF - I think winter '95/'96 might be something to look at as an analogue.



Spot on. Seasonal forecast accuracy due to model ability is a total fallacy. It's easy to go for the most likely outcome. That doesn't make it smart.

Bottom line is no one, including the experts have a clue what will happen and they'll admit so. That tells you all you need to know. Anyone who believes any model has a decent hang on it is only kidding themselves. LOL


Seasonal forecasts are pure guesswork,impossible to forecast and all these models you can read whatever you like into them.Its akin to predicding the lottery numbers.I really can`t believe this thread was started early september and is as long as it is.Will the summer 2014 prospects thread start in early march??



Does it really matter?


If people don't like the thread then stay out of it .............surely??


There are long range charts out there , so let them be posted.


Yes they are unlikely to be correct but no harm is done , it isn't life or death, just weather


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


jamesthemonkeh
16 November 2013 17:17:22

Originally Posted by: Matty H 

Originally Posted by: NickR 


Originally Posted by: Matty H 

Originally Posted by: Ally Pally Snowman 


Originally Posted by: nickl 

With the ec seasonal update going for a + NAO winter, I don't know of any models predicting anything other than average to mild. Anyone remember chasing northerly topplers in gefs low res? Methinks we have been spoiled over the past few years. Can all the models be wrong?


 


The EC seasonal goes against the EC 32 dayer which is blocked until at least Mid December. The EC seasonal is notoriously poor.


 


 



None of them are any better than the other.


I seem to remember one of Gavin's video summaries in around late April/May looking at what the long range models were forecasting for the summer, and pretty much all of them went for a wet, cool summer. Indeed, people at the start of June when a decent spell didn't quite materialise as hoped for were saying that that was it for the whole summer, at least in part based on those LRFs.


In other words... YES, they can all be wrong. And might be said to be a total waste of time.




It's not even a "might", Nick; they ARE a total waste of time.

I often read people counter-claim that it's about trends, not specifics, which is fine, but all of them are complete crap at that as well. Every now and again one will be vaguely accurate, but that's always going to happen due to law of averages.

Without wanting to bang on about it, seasonal forecasting and its associated threads are a waste of time. As I said the other day it's like commenting on when you think you might next catch a cold, or win a tenner on the lottery. There's no tool for predicting it, just several tools that attempt to, but can't possibly do so as we have no capability.


I think it depends on how one interprets them.  If one takes FI output for example, as set in stone then one would issue a different forecast every 6 hours.  They are a very useful tool in picking up trends to be able to make medium-long range forecasts, as is knowledge of historical weather patterns, but one has to see through the whole range of output and know when to ignore it too.


I use them to make forecasts and have a reasonable success rate in the medium-long range, so if an amateur like me can then I am sure those far more educated and experienced do make good use of them.


They are absolutely not a waste of time for me.


Matty H
16 November 2013 17:24:23
You've contradicted yourself a bit. If you admit they change ever 6 hours then how do they "pick up trends"? Eventually one run will be roughly accurate, so who decides when that is? You cant go back and say such and such model picked this up on the 06 run three months ago.

Ok, lets simplify this: someone please post the link to the outlet that accurately forecasts seasonal weather on a regular basis. If we assume there are ways of spotting seasonal trends then there will be an outlet out there that also knows this (unless its a weather forum secret?) and will have taken the time to use this reliable information to produce reliable seasonal forecasts.
nouska
16 November 2013 17:36:20
http://i.imgur.com/WIc3V18.gif 

The fact that it abruptly changed to no signal as the month opened might have been a good indication for a negative anomaly for the month in its entirety. It was too late for the CET guesses by that time - the NOAA upper air analogues seem to be a better indicator.

http://www.cpc.ncep.noaa.gov/products/CFSv2/imagesInd3/euT2mMonInd1.gif 
Saint Snow
16 November 2013 20:53:10

Originally Posted by: Matty H 

Originally Posted by: nouska 

From the tools available and reading about weather drivers, the milder, zonal outlook in the models is understandable - it is what known physics suggests. It might give a rough idea for the large continental land masses - for the UK, pretty hopeless as the skill level masks on some of the output shows.

Add in the the possible circulatory effects of Arctic ice loss and low solar cycle; all bets are off with regard to what is in store this winter.

In the words of Gooner and JFF - I think winter '95/'96 might be something to look at as an analogue.



Spot on. Seasonal forecast accuracy due to model ability is a total fallacy. It's easy to go for the most likely outcome. That doesn't make it smart.

Bottom line is no one, including the experts have a clue what will happen and they'll admit so. That tells you all you need to know. Anyone who believes any model has a decent hang on it is only kidding themselves. LOL


 


I personally think LRF's are like predicting the result of several football games. You can study form and get an idea of what should happen - but the likelihood is that most of the time one or more results go against you. With hindsight you can often see where you should have gone differently.


The weather is not perfectly chaotic; it follows established rules. The problem is we just don't know all the rules it follows - there are just too many of them (enough to give the impression of it being chaotic). And, of course, there are always certain unponderables, like solar input or (usually to a lesser extent) volcanic activity.



Martin
Home: St Helens (26m asl) Work: Manchester (75m asl)
A TWO addict since 14/12/01
"How can wealth persuade poverty to use its political freedom to keep wealth in power? Here lies the whole art of Conservative politics."
Aneurin Bevan
Gooner
17 November 2013 08:37:24

http://modeles.meteociel.fr/modeles/cfs/run/monthly/runs/2013111606/cfs-8-3-2014.png?06


JFF JFF JFF


This would upset a few


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Gavin P
17 November 2013 10:09:29

Hi all,


Here's the Sixth Winter 13-14 Round-Up video;


http://www.gavsweathervids.com


Looking at SST's, snow cover, solar, etc...


 


Rural West Northants 120m asl
Short, medium and long range weather forecast videos @ https://www.youtube.com/user/GavsWeatherVids
Gooner
17 November 2013 12:15:55

Originally Posted by: Gavin P 


Hi all,


Here's the Sixth Winter 13-14 Round-Up video;


http://www.gavsweathervids.com


Looking at SST's, snow cover, solar, etc...


 



Cheers Gav , as long as it is milder comapered to '63 we don't have a problem


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Charmhills
17 November 2013 12:22:58

Originally Posted by: Gavin P 


Hi all,


Here's the Sixth Winter 13-14 Round-Up video;


http://www.gavsweathervids.com


Looking at SST's, snow cover, solar, etc...


 



Just call it how you see it Gav.


Reguarding the cough, I had a nasty cough which lasted from mid March though to early May but it finally went after that.


Just hung in their it will go.


Loughborough, EM.

Knowledge is power, ignorance is weakness.

Duane.
Steve Murr
17 November 2013 14:21:30

http://forum.netweather.tv/topic/78461-model-output-discussion-131113/page-73#entry2837073


 


post 1442- ive put quite a chunk of info up there I thought it may be of interest to some- especially on changing paradigms...


 


S

some faraway beach
17 November 2013 15:00:34

A fascinating read from Murr there. First the importance of having a N American low positioned to advect mild air up the west coast of Greenland to inflate a high there; then the extraordinary inability of GFS back in January to model a split trough; and finally a vivid illustration of how patterns over the Pole appear to have completely reversed in the last five years, to the extent that no model may yet be able to generate high-latitude blocking to the extent that it now occurs in winter.


2 miles west of Taunton, 32 m asl, where "milder air moving in from the west" becomes SNOWMAGEDDON.
Well, two or three times a decade it does, anyway.
Matty H
17 November 2013 22:28:06
A recent Fergusson tweet:


John S2
17 November 2013 22:52:03

Originally Posted by: Steve Murr 


http://forum.netweather.tv/topic/78461-model-output-discussion-131113/page-73#entry2837073 


post 1442- ive put quite a chunk of info up there I thought it may be of interest to some- especially on changing paradigms...


S


Interesting post. Thanks.

Users browsing this topic

Ads