Uncertainty

Some serious strat warnings now showing up even in the normally conservative geps and now consistently in the GEFS.

So the JMA is either consistently wrong or has pulled a blinder…

Bit of a wacky NH profile that! As expected, colder charts appearing… People have been writing things off like it’s late Jan 2020. There are some times you know that the writings on the wall, this isn’t (for the time being anyway) one of them.

Arpege looks to be following Icon’s lead. I have a feeling we’re going to see some colder charts this evening, both the early models keep the esb low twirling around the east coast allowing the wedge of heights ahead of them into the N Atlantic. This wedge will be crucial if we are to have a cold Christmas…

ECM with the east greenie wedge!

It hasn’t shown blocking and busted yet this winter? If we get too late Jan in this position then yes, absolutely it’s another brick in the failure wall but not yet. This winter is, and always has been about the post strat disruption / early 2024 roll…

Jan week 2 Jan week 3 Jan week 4 (first time we’ve seen this come into view) @ICE COLD so 8th Jan onwards @blizzard81 without more mjo amp we were never going to get much from the pre Xmas spell. The above looks to be a reflection of the strat weakening and heading on a jaunt to Siberia. Verifying the above will make or break winter…

Best ec46 yet for Jan…

It’s had a mostly consistent signal for many runs and reflects the seasonal modelling and expectations for the period. It can be useful if it backs up other expectations and / or is notably consistent.

Half the extended eps go for Atlantic / Greenland heights I’d imagine the members don’t necessarily look as good as cluster 1 might suggest but it’s a good step nonetheless.

Recent gfs Ops have shown that such a block is plausible, with the evisceration of the tpv eastwards and the inclination of the trop to reflect the strat there is certainly potential for such height rises - though a wedge might be the most we can hope for and even then, it’s not the favourite just yet… hopefully there’s at least one cluster that has a go…

Quite a big change in the euro / Atlantic sector on the geps for the Xmas day period… 0z 12z The 12z gfs looks remarkably similar so caveats aside this pattern is looking the favourite on tonight’s modelling so far The 12z geps pushes the trough through sewards and has a tiny hint of Atlantic height rises upstream. The 0z had swerlies and a euro high by this point. (They do return soon after, which also looks likely). No doubt quite a lot of output this afternoon would permit snow (with a lesser possibility the further s one goes) which is a tantalising prospect, even if it’s not the powerhouse easterly or 2010 style synoptic many of us crave. I still feel there’s a chance of a disruptive wind event too but it’s pin the tail on the donkey stuff to hazard a guess as to where. Also I know there’s a met thread but looks like they saw past last night’s pretty dreadful ec 46 and have started mentioning the low poss of a more significant spell in mid Jan. I still think this is where our perception of this winter will be defined but we could be two cold spells in by that point which is better than many efforts. Finally, the back end of the gfs is almost excellent, with a Greenland wedge pipped to the post by a stubborn old friend of ours… (or not) It has shades so last night’s 18z which was a best case scenario run. It also, as it has consistently recently, moved the strat focus over Siberia and away from the pole. This could lend support to the Atlantic height rise attempts.

Starting to see quite a lot of ens runs with some seriously low pressure near the U.K. - some in and around the N sea, If the whole lot does eject se wards there could be a serious storm to contend with around the 21st… just a possibility at present… Also, @Allseasons-Si I’m sure you’d agree that if we were offered the following anomaly for Xmas we would take it every time!

Interesting and potentially crucial that the ecm, cfs and JMA weeklies are on the same page vis early - mid Jan. The ec 46 has been keen on a scandi trough dominating this period but can’t decide on the Atlantic / Greenland sector. The cfs has recently started to trend similarly. It’s not often in winter both of these models concurrently advertise a non-standard pattern such as this. The key takeaway though looks to be the inevitable Xmas +nao translating to a scandi trough with time. 1st week of Jan Ec then Cfs 2nd week of Jan 3rd Week of Jan The JMA looks to be taking a similar approach and has been posted elsewhere tonight. Taking the models at face value a Scandi trough pattern looks very likely but the strength and amplitude of any Atlantic ridge action remains very tricky to call. Plenty of interest in the strat too and no doubt there will be a possible link to the relocation of the strat vortex and the trop reflecting this. Still good reason to believe the mjo will emerge into 8/1 around month’s end too. My faith (whilst it has wavered over the past few days) remains strong that we will see a notable cold spell in the coming weeks. Plenty to look out (and up) for in this critical, winter defining period.

Something to cheer you up @bluearmy

Also I can’t seem to post the Copernicus charts properly but despite Glosea and ncep the multi model mean is a remarkable run with a NW high anomaly and a central euro low. It’s the best we’ve had progged at this stage so certainly the promise is still there for this winter which is presently 10 days old…

That is one deep euro trough!

Icon has the hp further N than this time yesterday. A day later it almost manages an easterly in the S and looks to be thinking about retrogression.

It wasn’t as good in the strat either. It seems like quite a lot was/still is riding on that tropical push and if it does fail to materialise we could be looking at the next cycle and thus most of Jan could be a slog… Then again maybe just a duff run, 12z looks quite different. Am starting to get a few warning bells mind. The BCC seasonal is dire and it’s thrown me a bit. Meteofrance isn’t much better. This is no ‘winters over’ post -I still think the telecons will deliver this winter - but I’ve just got that nagging doubt starting to creep in. Think I’ll go eat some Pringles and watch some motivational speeches…

The 1st eps cluster is really interesting and there’s less +nao than this morning. Also a mean euro trough (vital) so definitely a more positive suite for those of a cold Christmas persuasion.

This is a really quite consistent signal pre Christmas from the NAEFS. If we get to this point, there are quite a few reasons to like this outcome… -The huge Aleutian low is going to keep the states warmer than normal meaning less energy /flatness into the Atlantic jet -There remains a signal for higher than average pressure over the Urals, keeping the cold bottled in and ready when the time comes. In combination with the aforementioned low, this will be heaping pressure on the strat above. - The pattern would suggest some members would have scenarios conducive to snow But the above is a long way off, and the At day 10 the 3 main models are trending too asynchronous to each other to have confidence The GEM heads not NW but to Scandi, a break in the Atlantic flow above allows the pent up amplification to blossom over and to the NE of the UK Here the high makes first contact with the Arctic high which effectively gives it something to latch onto. Sadly this means I don’t trust it one little bit as we have been mugged/scorned by Arctic highs a number of times in recent winters. The GFS sticks to its theme of a ridging Atlantic high Note the Arctic high is weak and distant on this run. And finally the ecm, as has often been the case recently, can’t make its mind up and has elements of both but can’t clear any real space for the heights to push N. Again you can see the Arctic high but it’s out of reach for the time being and the energy rolls over the top. It’s not as flat as some recent ec Ops though and these days I’m less concerned with it. I do think the eps backed off the NAEFS signal shown above last night so it would be good to see more amplification return in the extended on its 0z run. The conclusion therefore is that cold and / or wintery scenarios are possible from the post day 10 evolutions but there are too many options and there’s too little agreement to back a particular runner for the time being. Original post: https://community.netweather.tv/topic/99584-model-output-discussion-into-winter/?do=findComment&comment=4972556

This is a really quite consistent signal pre Christmas from the NAEFS. If we get to this point, there are quite a few reasons to like this outcome… -The huge Aleutian low is going to keep the states warmer than normal meaning less energy /flatness into the Atlantic jet -There remains a signal for higher than average pressure over the Urals, keeping the cold bottled in and ready when the time comes. In combination with the aforementioned low, this will be heaping pressure on the strat above. - The pattern would suggest some members would have scenarios conducive to snow But the above is a long way off, and the At day 10 the 3 main models are trending too asynchronous to each other to have confidence The GEM heads not NW but to Scandi, a break in the Atlantic flow above allows the pent up amplification to blossom over and to the NE of the UK Here the high makes first contact with the Arctic high which effectively gives it something to latch onto. Sadly this means I don’t trust it one little bit as we have been mugged/scorned by Arctic highs a number of times in recent winters. The GFS sticks to its theme of a ridging Atlantic high Note the Arctic high is weak and distant on this run. And finally the ecm, as has often been the case recently, can’t make its mind up and has elements of both but can’t clear any real space for the heights to push N. Again you can see the Arctic high but it’s out of reach for the time being and the energy rolls over the top. It’s not as flat as some recent ec Ops though and these days I’m less concerned with it. I do think the eps backed off the NAEFS signal shown above last night so it would be good to see more amplification return in the extended on its 0z run. The conclusion therefore is that cold and / or wintery scenarios are possible from the post day 10 evolutions but there are too many options and there’s too little agreement to back a particular runner for the time being.

Ec 46 giving the first sub seasonal hints that the January dream could become reality!

As @MATTWOLVES 3 says the zonal winds are getting into the actual - there’s an ssw on the way category As long as the monster Ural ridge verifies we’re going to be right in the game once the pacific starts to fire…

What a flippin fantastic chart that is on so many levels. Except for the stratospheric polar vortex. For him it would be bad.