[Model Output Discussion - Spring Has Sprung]

 bluearmy We had snow here in mid Essex without height. Start to Cricket also delayed at Colchester's Castle gfound.

[Snow and Ice Northern Hemisphere - Winter 23 /24]

Good morning everyone.

I thought I would post the attached link, which indirectly relates to ice coverage in the Arctic.

https://www.msn.com/en-gb/news/other/atlantic-ocean-circulation-nearing-devastating-tipping-point-study-finds/ar-BB1i39Vg

It is something I have often pondered- i.e. is the climate self regulating?

I note that it is only one season but we have more ice than in recent years, although the article has not caught up with that fact.

Kind Regards

Dave

[Model Output Discussion - Colder but how cold and for how long?]

12 hours ago, Midlands Ice Age said:

Claret047 (Dave)

I hadn't forgot your query above, but waited until it was quieter to respond.  

In general more data is good news.

However, if you have more data (assuming a normal distribution)  you also introduce more 'out of range' data.

Generally models use various techniques  for handling the threat.  Within the models you can check the data against other data for the immediate locality.   (If there is one - could be difficult to apply in the Arctic or Antarctic),  and this generally is quite effective. 

Another method that was employed a few years back was by using a pre-edit stage. This will check for data being within certain ranges.

It was employed by BOM and led to complaints that some data had been omitted.

It  is quite difficult to use ranges in the world models as they have ranges of from -80c to +60c, and the same goes for pressure,  rainfall,  etc.

I do not know what method is adopted for each model.         Perhaps some else can help?

These days most data is produced automatically and normally will not have errors. When something goes wrong it is fairly easy to see.

MIA  

Thanks very much David for your detailed reply.

[Model Output Discussion - Colder but how cold and for how long?]

I like the cold and snow, but it is not just that which enthrals me as far as the weather is concerned. Like you BFTP I like to see how the charts develop from one frame to the next and from 0Z to OZ, 06 to 06 and so on. How the change happens will be fascinating to watch.

Computer technology,  I believe,  can only go so far in determining what the weather will be like to any degree of accuracy much more than 5 days ahead. Perhaps the computers read too much information and the tiniest nuances magnify/distort the final conclusions. Perhaps MIA and other software experts may care to comment on this.

In the meantime we have about a week of cold weather in my neck of the woods with little chance of snow as things currently stand. At least the sun is out now and we have lost the North Sea clag that we have been enduring. 

Looking at the ECM chart someone posted a few moments ago it looks like a very windy and possibly wet spell is in the offing. I very much hope not as that is the last thing we want!
I intend to go out this afternoon and enjoy the weather we have and not lament what we could have had, and suggest my fellow southerners do the same. Me I am watching the mighty Chelmsford City play Wealdstone inn the 4th Round of the FA Trophy. Perhaps @Ice Day and other nearby posters might wish to come along and support their local team.

[Model Output Discussion - Colder but how cold and for how long?]

What a fascinating day of weather watching on here, with some really interesting posters from a number of more experienced members on this thread. It is difficult to keep up with all the posts coming through. Tamara and others make tis thread what it is.

As far as balloon information is concerned is this instantly added into the data on these super computers or if it is collected at 00 hours not make it into the charts until the 06 charts and the same with the other reading time is the information part of the next output?

I reckon the birds know what is going on better than I do currently. I have a sneeking suspicion that they have been peering through my lounge window at my pc to see the various charts I have bee4n displaying, and, as a result have eaten much more out of my feeder today than is usually the case. Normally I expect to replenish it every other day, but today I have filled it up twice! 

I must go know before I sound more like Bill Farkin than I already do.

Enjoy the chase. Don't forget 1947 winter didn't start in earnest (Where is earnest? I hear you cry) until about 20 January and so keep the faith.

[Model Output Discussion - Into 2024]

1 hour ago, Midlands Ice Age said:

A very good question and one that I have thought about myself after watching one of the American forecasters (on X) over there give his outlook  for the USA (using all the available models), for the next 7 days....

For interest only,  they are fore-seeing freezing conditions spreading in during the weekend and then across to all but the extreme east and north east by next weekend, with the possibilities of record lows.. So a massive change for them.

However interestingly, for all but the short term prognosis (where he used the GFS mainly, but for some precipitation charts he used  a 'blend' of the others) ,  he used the GEM and ECMWF models for most of his outlook after 3 days. Sometimes he would state that he had used a blended forecast (GFS 40, ECM 40, GEM 20), etc..  but mainly ECMWF. 

I have noticed this before when watching US forecasts that they frequently state that they are using ECM and GEM rather than GFS,  almost as if they do not think the GFS is accurate, in their corner of the globe..

As Paul  says above they use more or less the same starting data, but I am beginning to suspect that the GFS  is quite weak on any stratospheric medium outlook influences, when it gets to the 10-12 days ahead outlook,  They seem to be able to pick up at a way out timescale, but then seem to wander away from it again for a while,  until it comes back into more the reliable.....    

This 'feeling' is  shown by the way in which the GFS suddenly 'veered away' from the rest  at the start of this chase over a week ago now.  And we know from the ECMWF blogg (on SEVERE weather EU),  that  the GFS were not seeing any strat changes, when it was being shown that all other models had picked them up back in late December..

HOWEVER , could it have been that actually the rest left the GFS behind,(?? -likely in my opinion),   as they factored in the warming of the Stratosphere, and moved it into its tropospheric effects - even though it did not actually cause an SSW, it has certainly weakened the jet flows around the world. Perhaps GFS at the shorter range only use the tropospheric data and  then will slowly come back onside again.

It would also explain why the GFS was so good on the last cold spell - where it was totally tropospherically based, - and it seemed to wind it down to zero better than the other models..

Back to here and now again...We now see that ECMWF are seeing another rapid warming occuring at the  same time as GFS apparently veers away from the rest again.

\Will it be correct this time or will it come back into the fold as the effects of the latest warming actually become apparent at lower levels (possibly in 10 days time).

Last week the GFS  took quite a while to gradually come back 'in fold', (3days?) - maybe as they started picking up on the actual tropospheric influence of the partial and minor SSW which occured at the same time as the charts merged together again. 

Do they use different programs for their longer range compared to their more immediate  forecasts? Certainly we have seen sometimes how their 13- 15 days forecasts suddenly go totally haywire. (as shown up by the pub run?)

This would explain the type of behaviour of the models that many of the more experienced of the guys have observed on here....

That is the GFS picking up way in advance a pattern change, only to drop it ., and then come back to it again after the other models (about 10 days) have picked up on it and then the GFS  returns to the fold very slowly at days 10 to 5,

I am sorry if this post is difficult to follow, but it is quite difficult to describe the fluctuations of the GFS. - Sorry mods 

Note you GFS fans, I am  not decrying the GFS,,, but it is these highly visible times that it seems it sometimes behaves strangely - but in a consistent manner. 

We will see  whether the above is 'tosh' or indeed correct.

MIA

Hello David- Many thanks for your very detailed reply. Also thanks to @Paul for his informative earlier response.

[Model Output Discussion - Into 2024]

Good Morning everyone from a great fan of snow. Hoping what I am posting is not off topic but I would appreciate being permitted to ask a question of the more knowledgeable on this thread. 

Do all models use the same resources to collect their data in order to do their modelling? The reason I ask is that I believe the GFS is an American model (please correct me if I am wrong) and wonder if they have more information as far as modelling the area around Greenland. If so perhaps they can predict that area better than ECM or UKMO. Hopefully that is not the case as we all want the evolutions of the other two models to be correct. 

[Model Output Discussion - Into Winter]

39 minutes ago, Jason M said:

Have a feeling your going to struggle to 'paint' over that particular typo! 

Hello Jason.

It was a deliberate attempt to be humorous and so I will not attempt to gloss over it.

[Model Output Discussion - Into Winter]

47 minutes ago, Snowmut said:

Trouble is we're all hoping for a place in the champions league final, but it's increasingly looking like a quarter final exit in the Johnstones paint trophy is the best we can hope for!  (Other paints are available!...Watching some Dulux dry as we speak!)

You are showing too much emulsion about the current charts! I am no expert but believe that all the current uncertainty may be a good thing as it highlights that even with the most sophisticated of computers we are none the wiser. 

I do sometimes wonder if the technology is too developed taking too many factors into account and if it was less so a clearer pattern would be apparent. Am I just waffling on or do others luddites like me agree?  

[Snow and Ice Northern Hemisphere - Winter 23 /24]

Just a quick note from me to wish all on this thread and their families  a very merry Christmas and a prosperous and healthy new year. I would like to thank David (MIA) for all his hard work in posting so much information on this site to make it so interesting and to the others for their great contributions.

Judging by comments we are to date in a reasonable place as far as the amount of ice that has accumulated within the arctic and long may it continue.

[Model Output Discussion - Into Winter]

2 hours ago, Midlands Ice Age said:

Carinthian..

 Your mentions of a 'curveball' low crossing the north east of Scotland and moving down the North Sea and its impacts reminds me of one of the really horrible moments of the 20th century. Particularly to the East Coast and the Dutch coastline.

Not many people will be aware (or more probably - see it happen) that the event caused the greatest loss of life in the UK of the last century.

It has become known as the North Sea disaster.

That of late Jan 1953 when a low formed between Greenland and Iceland and ran SE towards the northern tip of Scotland. It then went for an explosive cyclogenesis (bomb in todays terms ), as it moved SSE down the east coast and in towards Holland.

Nearly 3000 people were killed in total on both sides of the Channel, with around 300 in the UK. Whilst not wishing to spread alarm, I do feel that we need to watch this situation very carefully over the next 6 days. It could be  a Christmas wrecker. 

I remember the night/evening well in North Nottinghamshire out delivering groceries with my father and being invited in for drinks, and at one house they had a tele (wow)  and were showing scenes of the conditions on the east coast with nearing 100 mph winds and  with us a raging northerly and occasional snow flurries.

A few links which may be of interest below -

 Great North Sea flood of 1953 remembered 70 years on - BBC News

 https://www.bbc.co.uk/news/uk-england-lincolnshire-64414388 

The Met Office will be aware of this situation I hope. 

I have included the re-analysis for the event so that one can see the similarities.

 https://www.meteociel.fr/modeles/archives/archives.php?day=30&month=1&hour=0&year=1953&map=7&region=&mode=2&type=ncep

PS Perhaps the Iberian high made the situation even worse by squeezing the pressure gradient.

In fact there were a lot of similarities world wide with the main vortex transferred over to Siberia. 

MIA

Hello Dave. I am from Essex and am old enough just to remember the occasion. I have a book at home entitled the Great Tide by Hilda Grieve and is a very interesting read on how the aftermath of the flood was handled before the days of mobile phones and the landlines were out of operation. I had the pleasure of meeting Hilda a few times as we both worked for Essex County Council and she popped into my office to see one of our architects to whom she was a personal friend. If the book is still in print I thoroughly recommend it.

[Model Output Discussion - Into Winter]

It is good to be back. My PC had a 400 error message that prevented me gaining access to this site and it was like having my arm chopped off

I am now just playing catch-up to see what I have missed over the past few days. When I last was able to visit the site there was great excitement about some brutal weather in the early reaches of FI. Looking at some of the more recent posts I am not sure if this is still the case. Am i correct in this assumption?

[Model Output Discussion - Into Winter]

Good evening everyone.

It is certainly fascinating watching the various model outputs struggling to pinpoint what is likely to happen on late Saturday let alone further ahead. Reading the very insightful posts is educational and makes this site what it is.

I am old enough to remember the winter of 1962/3 and that is what made me interested in the weather. Things do not appear to have changed a lot from those days when it comes to predicting the fate of cold air entrenched over the UK. Listening to the 17.55 weather forecast on the BBC Home Service (the forerunner of BBC Radio 4) the outlook was always along the lines that milder air was going to sweep in from the southwest as per forecasts provided on European models whilst the USA model was stating the cold weather would continue: And so it did, with either the cold air meeting the block and retreating whence it came or going over the top of the cold air for the weather to remain frigid at the surface. These days of very powerful computers, satellites and more observation points one would expect prediction 3 or so days ahead to be more easy, but judging by the changes in today's modelling to my untutored eyes it does not appear to be the case. 

To those that know far more than I perhaps they could advise why this is the case with all that is now available to guide forecasters?

[Model Output Discussion - Into Winter]

1 hour ago, MATTWOLVES 3 said:

Listen here you lot...I've just been to the Dentist as I was in pain..she said its all over for that tooth matty...I said listen here....nothings over till I say its over..you get my drift! OK she looked at me like I had a screw lose...but I never give in and sometimes things can be saved when its against the odds

Those 6z ens show some fruitful possibilities moving further forward...and let me tell you this I'm still learning about teleconnections. And I thank Tams a lot for that as she's answered many of my questions over the last couple of years..but when somebody first mentioned wave breaking too me,I quickly found myself on a Australian surf forum yes I'm still learning  and Tamara is gonna have her work cut out with me one thinks.

In the shorter term we have cold and some snow risk for those around the NE especially..but do watch out for little features cropping up at short notice. Beyond this point it trends less cold but this is not yet 100% nailed down...if we keep that cold block over scandy and a Canadian warming and favourable mjo cycle all come together,we could be looking at much favourable syonotics later next month.

Remember folks the drivers are our friends this year!

I hope you are OK now. What time was your appointment? Was it tooth hurty?

BTW I agree with you as far as the current cold spell is concerned and that it will be far more resilient than the models are indicating.

[Model Output Discussion - Into Winter]

3 hours ago, Severe Siberian icy blast said:

One morning of a breakdown been a wk away still and suddenly we're going into a two week period of zonality this place is hilarious.. we have had cross board agreement of very cold hair the last few days but now it's definitely right 

 

I always wear a hat when I go out and so my hair is rarely cold

[Model Output Discussion - mid Autumn]

Someone on here a  little earlier mentioned the Beast From the East and it got me wondering why we have not heard from David from Peterborough recently.

I used to enjoy his postings. I trust he is OK and we will hear from him soon with his input.

[Storm Ciarán]

1 hour ago, IanT said:

My friend’s son goes to a state school in nearby Hampshire. It’s closed today because of the “major incident”. Meanwhile my son is at rowing training with his (independent) school. We had a message at 0600 saying that that training was on, and that they would make an assessment on river levels/condition and the overhead weather at 0800. If conditions weren’t considered safe the boys would run together (about 4km) from the boathouse to the school and train together in the gym there.

 

Which set of kids are getting the right messages about risk management, perseverance, commitment, attitude to life etc…?

Both sets. The independent school is doing the correct thing by hopefully undertaking a robust risk assessment, whilst the state sector school is possibly using local knowledge as to whether roads are flooded/blocked by debris/wind strength is and is likely to be and whether their teaching staff are able to travel to the school. These days few teachers live in close proximity to their school. We don't know the situation and so it is a tad foolish to make broad-stroke comments without knowing the entire suite of facts.

[Storm Ciarán]

7 minutes ago, bevo said:

I’m very happy to make my own decisions based on fact at the ‘right’ time, ie can my children go to school this am. Yes! Not using data that was based on weather models well over 36 hours ago. Ps. I didn’t scream in 1987 or cry when I walked in a snow drift. Happy Thursday all. Do take care as life is full of risks  

Good for you. Unfortunately every time people with the same attitude as you think they know best there are some who tragically end up in the morgue. I am a semi retired health and safety advisor. The number of times when I have investigated an accident I have heard wording to the effect of "I have always done this previously without any problems" Not only do you put yourself at risk by such a cavalier attitude, but potentially others who may be sent out to rescue you/retrieve your body.

Going back on topic. Very wet here in mid Essex. Was very windy during the night with heavy rain, but wind is much lighter now. We await to see if the storm takes a left turn or if the more extreme weather forecast for later today does not materialise.

A neighbour whose back garden backs onto mine has lost the cover to the top of his gazebo. I have found it shrouding my sun umbrella stand and I will have to return it to him when he returns from work later today.

Stay safe everyone.

[SE, London & EA - Weather Discussion]

2 hours ago, Sparky68 said:

Could have done with a Canoe for the commute in, that's horrible out there.

I bet the chicane/ traffic management system that reduces road width on the outskirts of Godmanchester is flooded. It appears to be a common issue during heavy rain.

[Model Output Discussion - Mid Summer Onwards]

46 minutes ago, claret047 said:

Hello Mark,

I trust you are well.

The charts look fantastic and hopefully it comes to fruition. With light winds I hope we are not plagued by fog that could be reluctant to clear as that would subdue the daytime temperatures. What do you and others more knowledgeable than me think?

I hope we have good weather as my wife has been through a lot lately with a heart condition and with blood thinners she bruises and cuts very easily which means she is constantly having wounds dressed by a nurse at our local surgery. Tomorrow she is having a cataract removed if her heart is OK for the procedure to be performed, I want to take her away for a few months around about her birthday on 9 October all being well and the weather does as its told.

Re my final sentence. I am not that wealthy. I should have typed "days" and not "months "

[Model Output Discussion - Mid Summer Onwards]

7 minutes ago, Mark wheeler said:

UKMO 156 to 168hrs looking plumey too  . Lovely Jubbly

Hello Mark,

I trust you are well.

The charts look fantastic and hopefully it comes to fruition. With light winds I hope we are not plagued by fog that could be reluctant to clear as that would subdue the daytime temperatures. What do you and others more knowledgeable than me think?

I hope we have good weather as my wife has been through a lot lately with a heart condition and with blood thinners she bruises and cuts very easily which means she is constantly having wounds dressed by a nurse at our local surgery. Tomorrow she is having a cataract removed if her heart is OK for the procedure to be performed, I want to take her away for a few months around about her birthday on 9 October all being well and the weather does as its told.

[Storms and Convective discussion - August 2023]

4 hours ago, fujita5 said:

I look to be in a good position here in Clacton. I need to be up relatively early in the morning but can feel an all-nighter coming on. May try and grab a bit of sleep early this evening and get up about 11 to see what's happening

I will be looking to the east from Chelmo then. 

[SE, London & EA - Weather Discussion]

A few flashes and rumbling, but little rain thus far.  Radar looks threatening to the west of here.

[Model Output Discussion - Snow Watch limited edition]

11 minutes ago, Updated_Weather said:

How do you think Colchester may do from this evening?

Are they playing? Seriously you are that bit further north than us, although a bit nearer to the coast, but you could well be OK. It is a matter of wait and see as it appears to be all so finely balanced.

Friday I am really interested as my wife and i are driving up to Huntingdon in the afternoon and there is great uncertainty as to how far north the milder air will travel.

[SE, London & EA - Weather Discussion]

13 minutes ago, DJ Fart said:

Light drizzle here this morning in on the Essex/Suffolk border...bloody cold though!

Ditto in Mid Essex, although it was a bit heavier for a while. Looks a bit brighter now. I guess it will be a case of lamp post watching over the rest of this week once the Arctic air is established over us.