bluearmy

would say that the 12z ecm looks a much less messy way to get to the cold flow than has been shown by some of the other runs. initially less cold due to no tightening of the pressure gradient around T96. will be cold at the surface though!!

if you can bear the wait, at least you'll get exeter's take on the ecm evolution with the T120 FAX later on.

The massive height rise over greenland is certain. what happens to the jet to our south and the interaction of that with the mass of cold air plunging sw is causing the models a lot of problems. this is a rare pattern(especially early in the season with higher sst's north sea and lower in the med than might be expected). the bones are there but to expect to see flesh more than 4 days out is pretty futile IMHO. great runs to look at but the chance of verification? not high as far as detail is concerned. what i will say, remembering the heady days of the seventies/early eighties, is dont under estimate the power of a mass of very cold air. the models certainly will.

the parallel is quite a similar evolution to the ecm. imagine that we were a week ahead of now - we'd be saying: fantastic cross model agreement out to t240

the extended ecm ens posted above show the shortwave at the end of the op run to be an outlier. (not a surprise given the range). however, if we get a brisk ne flow and the uppers are below -8c, i think we could see a fair amount of snow on the eastern side. the jet looks to be progged a bit too far south to deliver frontal precip so we're going to have to rely on the strength of any onshore flow to generate showers. given that the north sea is a little on the warm side at the moment, we do need uppers below -8c IMHO, unless the flow is very fast in which case there will be less modification. all very uncertain at a range beyond a week but the nwp is very bullish about the block over iceland/greenland and the southerly jet. http://www.meteociel.fr/modeles/naefs_cartes.php?ech=192&code=0&mode=0&map=1 NAEFS continue to paint a phenominal picture beyond T240. remember that 50 ensemble runs from two different models should be returning to automatic pilot beyond t240. the jet stays well south and strong so as time passes, even if we miss the snow train to our south over europe, eventually, it will come our way and with the continent snowbound, any breakdown will be a good one. seems a crazy time model watching and everyone seems to be waiting to fall off the rollercoaster.

the ecm 12z is soooo different in the w atlantic with the trough energy headed se instead of ne. where there was a high this morning, there now sits the trough. can we really trust what we are seeing beyond T120 ????

528's into the south east on mondays UKMO. the ecm 12z has upgraded on the 00z on the past two days. lets hope for the hat trick.

I've missed a lot of the comments today but the GFS 12z output (op and parallel) is tending towards the middle ground between the steller runs we have been seeing and the ECM 00z. remembering that the ecm 12z of yetserday went some way towards the GFS evolutions i would think we saw the worst case scenario from ecm this morning, the best case scenario on gfs this morning and the 12z's will offer us a better picture of what is likely next week.Of course this is still a way off and the real cold may well retrogress back towards us over the next few days output. however, as we approach verification, if the pattern begins to downgrade across models, we should take notice of it and not dismiss it. it is, after all, the form horse for the cold to be east or south when it finally arrives.

that shortwave is the one that brings in the cold on ECM T240 having travelled all the way around our block and set up residence n italy

parallel progressive and scary in FI - i mean real sustained cold

http://www.meteociel.fr/modeles/naefs_cartes.php?ech=192&code=1&mode=2&map=1 not sure i've ever seent the jet make it full circle and at T300!! superb pressure anomolies from the 50 ensemble runs of GFS and GEM ensembled together into the NAEFS.

i know its all FI, but anyone spot where the p/v has gone at T216 ??

the options for the block forming over us at the w/end are beginning to reduce. it looks as though the southerly jet will take lower heights across to our south preventing it from sinking. ecm op 00z would have you believe that shortwaves to our north will prevent it from ridging to its arctic cousin providing us with a ne or e flow. if the WAA up the west side of greeny courtesy of the eastern canadian depression late this week doesnt have enough oomph, then the atlantic will be knocking from the west and it wont be able to retrogress to a greeny block. it may well turn out that it just sits there, above us for a fair old while. thats what the ensembles have been telling us but we've talked ourselves into believing that they are just slow on the uptake when it comes to an easterly. if we can bear the wait, we will find out in a couple of days when the track of that low out of canada interacts with the blocking from the arctic. WAA or not WAA, that is the question.

i recall it well steve but i dont think conditions in the arctic were so beneficial at the time. meanwhile, the eagle made a decent call re the temps from the 12z ecm. a bit of a surprise that de bilt isnt sub zero at days 9 and 10 with a continental flow but then the uppers arent that low at this point despite thicknesses mid 520's.

http://www.meteo.psu.edu/~gadomski/ECMWF_12z/hgtcomp.html wow! just look at the supporting lower heights to our south. fantastic.

todays JMA at t192 isnt the best but its not terrible at such a range

just a taste on the latter stages of ecm what 'normal' might be like for us if the earth span in the opposite direction. (OK - bit far fetched but how often do we get to see that!!) by the way, for me, the most important trend from the 12'z is the strengthening of the southern arm and the lowering of pressure to our south in early fi.

T2m temps always start like that. no worries about initialisation on the 12z GFS

ens still not getting it with the mean upper -6c not quite reaching the dutch/german border.

seeing as we have a general mood of despondancy in here tonight, here's some prose from the NOAA discussion this evening: LONGER TERM D+8 ANOMALIES AND CORRELATIONS ARE IN GOOD AGREEMENT ON A DOMINENT STRONG POSITIVE HT ANOMALY IN THE BERING SEA WITH AN EXPANSION EWD TO ANOTHER POSITIVE HT ANOMALY OVER GREENLAND AND ICELAND. A BROAD AREA OF PAC NEG HT ANOMALIES DOMINATE THE ERN AND CENTRAL PACIFIC BENEATH THE BERING SEA POSITIVE AND A MEAN TROF PERSISTS OVER ERN CANADA. BY D+11 THE LARGE POSITIVE HT ANOMALY OVER THE BERING SEA BREAKS DOWN WITH THE MEAN POSITIVE HT ANOMALY SHIFTING EWD ALONG RIDGING OVER THE CANADIAN ROCKIES. THE ERN PAC TROF DEEPENS INCREASING THE NEG HT ANOMALY WHICH BECOMES THE MAIN NRN HEMISPHERE FEATURE. ERN NOAM TROFINESS PERSISTS AND POSITIVE HT ANOMALIES CONTINUE IN THE NORTH ATLC NEAR ICELAND. ALL OF THIS CORRESPONDS WELL TO THE GFS ENS FORECAST OF A STRONG NEG AO/NAO AND DEVELOPING + PNA OVER NOAM AND ARE A GOOD MATCH TO TELECONNECTIONS. PROLONGED INDICATION FOR A WARM WET WEST COAST WITH INLAND ROCKIES RIDGING AND A COOL EASTERN HALF OF CONUS. CONTINUED ANALOG YEARS SHOWING UP OVER THE PAST TWO WEEKS INCLUDE 1963/1969/1977/1981/1985/1995/2002/2005. i especially like the second para with the ref to pos anomolies near iceland and the analogue years look pretty good to me. wouldnt normally post this as its automated at w/ends but given the NOAA discussion, it obviously has support: http://www.cpc.ncep.noaa.gov/products/predictions/814day/814day.03.gif

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png significantly though, the control goes with it :lol:

reckon turkey is a better bet with the black sea and that deep cold air

get used to it its only the 5th of december - your head will be real sore by march

the input data it runs with. could be any number of things, but the result for our little part of nw europe is significant. still plenty of 15% spread sypnotically in fi on the GEFS as GP alluded to.

its clear from the ens that the GFS 12z suite has picked up a signal for there to be more energy in the atlantic jet later this week and for it to head ne rather than se. its probably as simple as that. take into account that this follows the trend from the 06z run. whether the run is correct will be known by tomorrow when we will have seen more runs from other models and also GFS. GEM may well have picked the signal first again. however, unless ecm 12z heads in this direction, i will hold onto the hope that GFS is plain wrong.