nick sussex

There’s bound to be more changes with that as you can see the models are wringing every last bit of drama out of it .

It’s the nuisance shortwave near Scotland that’s causing the issues . You’ll see it meanders around . It needs to head ne or become absorbed much more quickly .

Given the overwhelming support for Greenland blocking that’s now likely to verify . The question remains where exactly it sets up. As I mentioned earlier the safest block is the Omega one . The huge cross polar blocking less so. Earlier there remains some uncertainty with the depth of cold associated with the easterly . Snow wise in the form of showers we don’t have a lot of instability to play with so these won’t be known until nearer the time. With the set up the east and se would see the highest chance . The T84 hrs fax chart does show that small occlusion close to the far se . The outputs currently don’t make much of that and have it as rain but it is associated with a small cold pool .

The models still playing around with the depth of cold re the easterly . A relatively new factor now is how much energy disrupts ese from the troughing in the Atlantic . As this disrupts it helps to nudge the high a bit further north and helps to advert colder pools westwards . Originally the high edged south . As for the Greenland high just a word about size . Bigger isn’t always better ! These cross polar flows look great on the charts but you’re better off with the smaller Omega block . The good thing about these types of blocks is you’re unlikely to end up with a west based negative NAO. Also the sourcing of the flow is more ne . Anyway we await the ECM , hopefully no dramas ! Original post: https://community.netweather.tv/topic/99706-model-output-discussion-into-2024/?do=findComment&comment=4994245

It’s day ten . As I said not too much of a concern at this point .

Sadly the coldest air will funnel into the Atlantic . The ECM won’t recover from that point . Anyway it’s just an op at day ten , miles away .

It’s just one op run so no need to to be too concerned at this point but the ECM shows that you can have the best ingredients and end up making a meal that’s not up to much .

We don’t want that high developing over Scandi . And now the block is too far west with the low phasing with the Atlantic low . A poor end to the ECM .

Day 9 okay . Need to box the high in now so it can force the low se . We don’t want heights escaping to the west nw .

We’re waiting for the all important day 9 . No dramas so far !

The models still playing around with the depth of cold re the easterly . A relatively new factor now is how much energy disrupts ese from the troughing in the Atlantic . As this disrupts it helps to nudge the high a bit further north and helps to advert colder pools westwards . Originally the high edged south . As for the Greenland high just a word about size . Bigger isn’t always better ! These cross polar flows look great on the charts but you’re better off with the smaller Omega block . The good thing about these types of blocks is you’re unlikely to end up with a west based negative NAO. Also the sourcing of the flow is more ne . Anyway we await the ECM , hopefully no dramas !

It’s by no means a done deal . Even if the high turns up exactly where that sets up is still uncertain . Coldies do deserve a change of luck . It’s more likely to happen as I’m still in Cyprus and not due to return for a few more weeks . The snow jinx is out of the country !

When does the NW server meltdown? The ECM with a much better orientation and placement of the high later . Overall an encouraging evening for UK coldies .

Unfortunately yes . But it also depends on the type of pattern . Easterlies are the most prone to implode nearer the time . A northerly tends to have a bit more leeway .

Amen ! We’re inching towards some conclusion on the easterly . The cold pool still though has a degree of uncertainty . Overall so far this evening a surprising turn of events . Normally once the models start sinking the pattern south you rarely get a reprieve . We’re not out of the woods yet though with the ECM still to come and another run just to be sure tomorrow morning if that backs the other models . Then if the easterly does verify then the cold pool will be centre of attention .

Regardless of what happens this evening the shortwave drama isn’t over in terms of the impact on the cold pool. The earlier ECM , GFS and GEM cut shortwave energy south through the high . Here the ICON doesn’t . So we’re going to have to wait to tomorrow to be sure of the initial correct evolution as we know from experience what a pain easterlies are to land .

Better jam today than tomorrow . You can have both so it’s not really an issue.

The ICON !

The models really making a drama over the shortwave north of Scotland . Here the ICON 12 hrs run manages to edge it ne and then it becomes absorbed by the high .

This cold pool chasing is turning into the Da Vinci Code . The latest ECM control run to T144 hrs isn’t as good as the 00hrs run at day 4 but better at day 6 .

Same old story ! These cold pools are so sensitive to minor changes in the position and orientation of the high . Still not possible at this point to forecast if there’s going to be any decent convection off the North Sea . The ECM brought a chance for the far se , the GFS 06 hrs has some flurries for the east . Hopefully we can get a resolution to this tonight as it’s now around T96 hrs .

Still some uncertainty with the depth of cold upto day 6 . The ECM is a little colder than last nights run. The shortwave to the nw is complicating matters . It looks mainly dry for the vast majority of the UK except for the far se where the ECM at T96 hrs brings a small colder pool. This may well disappear on the next run given the chopping and changing. So the far se there’s still a chance of some wintry showers with a brief window for convection . Snow wise I wouldn’t like to say at this point ! More later after my breakfast .

I think they used to have the regional verification which I agree is much more relevant .

The juries out on this Greenland high until it actually shows up closer to the time . The easterly continues to get downgraded with the uppers moving up. Very disappointing as this was the jam today scenario rather than the jam tomorrow which the Greenland high rollercoaster is turning into . We should bear in mind the epic fail of the ECM which had the coldest scenario and seemed unlikely to be wrong at just T120 hrs . It will at least turn drier which I’m sure is a huge relief to many and it will turn colder but unless there’s a huge turnaround with the ECM then any snow chances off an easterly look very unlikely . The ECM out soon , it owes coldies !

The ECM has been truly awful over the last few days. Wrong at day 5 and now it’s decided to have the worst medium term solution. As much as there might be a retrogression signal it’s not a done deal and there’s a lot of runs to get through before it comes into the more reliable timeframe .