nick sussex

Well Brian the gfs 12hrs operational run got so many key details wrong that its a non starter , there shouldnt be such a problem however with the GEFS ensembles but the gfs 12hrs run is likely to be way off the mark because of criticisms by NOAA. This is why I slated the gfs earlier today , but somehow in here the gfs is god and everyone seems to believe its every move, this is liable to cause alot of trauma, alot of this can be avoided if people take a broader view of the models rather than this fixation with the gfs. Its great for its free info but as we've seen can be prone to huge mood swings!

Theres no point discussing the gfs 12hrs run, its a dead duck! basically given the discussions at NOAA they're likely to ditch it as its got so much wrong.

For those worried about the gfs this evening it has been totally slated by NOAA this evening, the gfs , ecm and gem operational runs have been criticized but the gfs comes in for the most slating and in line with my earlier thoughts its been too progressive and especially with breaking down the east pacific ridge. This is good news if you want to see the ukmo verify, criticisms also of the ecm just to be fair and unbiased although the criticism here is for the early part of the run, the key here is that gfs has got the important east pacific ridge all wrong. http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

Good news for those that would like to see the ukmo verify. Discussions over at NOAA have slated the gfs, gem and ecm operational runs, the gfs gets a double dose of slating which doesnt surprise me. Lets hope the ecm gets the early part wrong but the later part correct seeing as its come up with a tantalising longer term trend to drive the jet even further south and build pressure westwards from russia. Heres the link and suggests the gfs has been much too progressive, the PV is expected to remain over canada and the pacific ridge is not likely to be going anywhere fast. http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

This just proves my point, if the gfs had shown the set up the ecm has from 144hrs onwards then this place would be bedlam but because its not the gfs everyones like whatever! :blink:

I'm stunned by the lack of comment or possible excitiment over the ecm this evening and the shift in the ecm and ukmo over the last day to take the jet further south, the gfs has also backtracked and improved its view of the jet and build of pressure from the east. Am I missing something here! do people know how close we are to a set up that happens perhaps once every few years if you're very lucky! Maybe I should go back and have another look at the ecm to see if I'm the only one to have access to some of the charts that show the most potential in years!

The ecm this evening is close to one of the best set ups seen in the uk for years! if people dont get excited about the ecm this evening then they've obviously been living in canada! of course this is in the longer term output but if this trend continues to take the jet south and build pressure from russia then we could be close to something very special.

IMO the ukmo 96hrs raw data is the one I would most trust and its less likely to go AWOL, as John H mentioned though you can't beat the fax charts as they have that human input thats been garnered over years of experience at dealing with similar synoptics. I would never back the gfs upto 96hrs against the ukmo fax charts .

Back the form horse or the model thats showed the most consistency which has been the ukmo over the last few days, the reason for so much trauma in here is the over reliance on the gfs which throws up four runs a day and sends people hurtling towards the prozac cabinet far too often. This is a common gripe of mine that this model thread ends up being the gfs discussion thread and the other models are often cast aside. The gfs is not fallible as we've all seen over the last few days, anyway lets hope the ecm keeps the upbeat mood going.

The gfs is all over the place as its overdone the energy coming off the PV and been much too progressive, the most consistent model by far during the last few days has been the ukmo. I hope the ukmo verifies even though its not great for my region but sensational for more northern areas, good luck up there and lets hope to see some good snow pics, still chances of some snow further south if that shallow feature doesnt head too far south into wednesday, of course theres room for changes either way especially as pressure now looks to build again to the north and ne.

Well Jude I would always follow the euro models for events upto 72hrs more especially the ukmo as they should really have a better idea of small scale developments for this side of the atlantic, because the pattern is on a knife edge the smallest detail will make a big difference. I'm sure this has been said already but the ukmo is excellent for northern areas this evening. :lol:

The first euro model of the evening in the shorter term disagrees with the gfs and still looks like taking a feature across the south. Heres the charts for the gme first. http://www.wetterzentrale.de/pics/Rgme361.html http://www.wetterzentrale.de/pics/Rgme481.html And now the gfs. http://www.wetterzentrale.de/pics/Rtavn361.html http://www.wetterzentrale.de/pics/Rtavn481.html If people are hoping for agreement this evening the early signs arent good for this!

Yet another backtrack from the gfs with the jet much further south than on the 06hrs run. But given the last few days its unlikely the other models will agree, disgreement at the moment seems a given. But I would say the gfs is not the model to be looking at for the shorter term detail, the ukmo and its fax charts will be the key here. The 06hrs gfs run ties in with the trend at the moment for the models to overblow the PV and push this too far east into the atlantic and swing widely between runs with this afternoons run now going back to something more resembling the true upstream pattern. The PV is expected to remain over canada and with pressure beginning to rise to the north and ne again then the outlook could be very different in a few days. No doubt there will be more changes, the model drama is unlikely to stop for quite a while yet.

Well only if its a happy and snowy ending and not loads of drama about a damp squib! You see just when it couldnt get any more complicated this shallow low over the north sea causes even more model drama, this stops a ridge from scandi backing west further south, this feature was originally progged to dissipate and allow the ridge further sw, on top of everything else causing problems this feature is another pain to contend with! http://85.214.49.20/wz/pics/brack0a.gif If the ukmo cant call where if any snow is going to be under 48hrs away then that really shows just how much uncertainty there is.

It just goes to show how much uncertainty there is when Peter Gibbs on radio 4 weather says that theres a chance of snow but they're very unsure, it could miss us and go into france or alternatively get as far north as Manchester! a nightmare to forecast only 48hrs out, this just about sums up the current models! F1 looks like now even less than 48hrs, incredible!

Great post Dave. Given the model output I should be throwing my toys out of the pram as I really dont think at present theres too much to be excitied about this close to the south coast. If someone made me give a forecast right here right now I'd go for this being a more midlands northwards event, including your location! It may come as a shock to a few people but I'm not obsessed about snow but more just seasonal temps during winter, I absolutely love sunshine and frost, snow is always a bonus in this country! I feel quite lucky that I saw decent snow a few weeks back and theres been many a winter when I've hardly seen a flake, so good luck to those that havent seen any and I hope theres a few pleasant surprises. Disclaimer( my thoughts are in regards to the overall model output as of today and the current trend) as we've seen lots can change, that was just to make sure my fellow southerners dont come after me because I dissed our snow prospects!

Theres no point looking at the GEFS ensembles for the shorter term detail which is so crucial. The GEFS is run at a lower resolution than the gfs operational run upto 180hrs, after 180hrs its resolution is better than the gfs. For crucial small detail in a knife edge situation the gefs ensembles wont tell you a great detail because we're dealing with tiny margins here, by far the best in this situation is the ukmo for within 72hrs.

That link I provided was from last nights discussions at NOAA, but the problem for the models is deciding how much energy gets thrown off the PV over canada and how quickly east it travels and then deciding what happens to that ridge from scandi, that shallow feature in the north sea is a real pain as it stops the ridge from scandi backing west further south and this then changes the surface flow ahead of the shortwaves. In a marginal situation small changes make a huge difference as one can see from those two differing views from the ukmo and gfs. On top of this the models are desperate to breakdown the pacific ridge driving more energy into the atlantic but they've been trying to break this down for the last few weeks and have failed so far, there is intense cold across most of the east usa and canada and the models IMO are being too progressive in trying to get rid of this so at this moment in time all the output is likely to be very unstable and for the longer term completely all at sea.

You have to love the gfs! from more snow than you can shake a stick at to a complete implosion all within 2 runs, even by the gfs standards thats going some! Heres the ukmo 48hrs chart from its latest 06hrs run. http://moe.met.fsu.edu/cgi-bin/ukmtc2.cgi?...&hour=048hr And heres the gfs for the same time. http://moe.met.fsu.edu/cgi-bin/gfstc2.cgi?...&hour=048hr For only 48hrs ahead thats quite a difference, the fly in the ointment is that shallow feature in the north sea which forces the ridge from scandi too far north, as ever in the uk theres always something to pop up and throw things into turmoil! Paragraphs 2 and 3 here suggests why the models are all over the place. Until the models get to grips with the energy coming off the PV then you can just view all output with alot of caution and given the difference between the ukmo 06hrs and gfs of the same time F1 starts at 48hrs! http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

Richard dont get me wrong I'm not in denial about GW but we shouldnt attribute every synoptic or the lack of it to simply this, it may mean however that we need a greater margin for error in terms of synoptics. However the following week is a nightmare to forecast because of what happens over scandi and how far south the jet goes. At the moment its like a model merry go round as one model downgrades the other upgrades, I wouldnt like to be in the ukmo this week as its a major headache trying to make sense of it all.

You have to laugh this morning with yet more model chopping and changing. The ecm has improved vastly from yesterday, the ukmo is still good for more northern and midland areas, the gfs is a bit of a downgrade. Ironically the model with the weakest scandi high yesterday the ecm turns upto today with a stronger ridge and a major battle at 144hrs. So IMO we still dont know whats going to happen as a level of chaos seems to have descended in the models and even more so than yesterday.

This tight clustering can be very misleading in F1, GP talked about this the other day its often a sign that the model will show a big scatter on the next run as it currently is going down a blind alley in F1 because of the pressure rise to the north. Expect to see those scatter more in the 00hrs gfs run. Could be yet more dramatic developments!

The true irony in all this is that if the low headed further south than progged Richard you may get some snow down there! and to start wheeling out the gem when you dissed it the other day because it showed cold really now just takes the model prostitution to new heights! B) I would advise you to read the link here regarding the NOAA discussions , makes interesting reading, also at the end of the day the resolution to all this maybe a blend of the 3 major models so in a sense they maybe all wrong! http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html The ukmo have gone with their own model in the fax charts whereas they went for a blend of the ecm and ukmo earlier in the day so this says alot for the ecm operational and what they think of it. Anyway I give up no matter what the charts say you will always be able to spin them into mild! this is not model watching its the weather according to WIB. I really do hope you see some snow then we might finally see an end to this relentless mild crusade!

I agree with you Nick F who knows where that low is going to track, in these situations you need a bit of luck to remain on the right side of the low and have a good spell of snow. It could still just as easily track into France and miss most of the uk or conversely it might track further north, however a track too far north will have implications for the next low pressure and will signify a weaker scandi high and hence worse longer term prospects. It depends what you're willing to risk in these circumstances, a short term spell of snow then likely back to rain or take your chances on perhaps a drier start to proceedings and a longer cold spell with perhaps snow chances later.

I think we need to have a reality check in here! even the fact that we're talking about the chances for snow and perhaps lots of it for certain locations is a major victory given the crap winter so far. Also events further north may mean an extension of the cold with a large swathe of high pressure building from russia all the way to iceland. This is all still up in the air and anyone looking at output past 96hrs for definite answers is going to find this all turns into even more of a car crash of emotions than it is already! And can we all at least celebrate one thing that this does not support the ecm!