nick sussex

I’m baffled ! The ECM was originally designed as a more day 3 and onwards model . We need to wait till the 6 hour steps show up later to see if it still takes at least a smaller cold pool further north and is just a bit quicker.

The ECM still the least interested with the deeper cold pool . It doesn’t even agree with the UKMO at T48 hrs !

Morning all Some of you are going to be delirious by the time any snow arrives and will be too tired to go out and play in it ! It’s a more respectable 7 am here in Cyprus ! Anyhow no major dramas this morning so that’s bizarre in itself ! Earlier we see the easterly cold pool uncertainty hopefully reaching a conclusion . The main models so far show a minimum -10 850s moving west . It is though a brief window where there could be some snow showers , current risk mainly towards the east and se . Also for our Irish friends , towards the south . The UKMO in particular looks best there . Hopefully the ECM will come on board as it seemed the least interested last night . As for the Greenland blocking that still looks on track but detail at this stage looks difficult given the chopping and changing over the Polar regions . We need to ensure the block is orientated in a favourable manner and located close enough for enough forcing to pull the coldest air south . That’s still the bit with more uncertainty . Anyway overall a nice start to the day .

If it wasn’t for the misery ECM then the easterly seems to have been upgraded this evening . Both the GFS and ICON 18hrs runs improve their depth of cold . It’s still a brief window of sub -10 850 air but still better than no window ! Even within T72 hrs and we can’t get agreement on this cold pool.

The ECM was the least interested in those colder uppers and had them over the Channel . So a bit of a surprise that the ICON now goes in the other direction .

Shortwaves forming to the north nw often don’t get picked up till closer to the time. This is why ensembles are not a great guide in certain circumstances as the lower resolution is less likely to model them at longer range .

The cross polar ridge is the beast in the closet in Poltergeist. It pretends to be your friend and uses you to control the others ! Don’t go into the light ! Sorry it’s one of my all time favourite films . But the point stands , these cross polar ridges like Siberian highs have an allure , they’re intoxicating but often come with a bad hangover . Show me an Omega block and the film analogies will end ! As I’ll be much happier !

Not sure about the ECM op. The cross polar ridge looks great at face value but can be too big for its own good . It all looks very flabby to the nw . Not impressed . There’s no real oomph to bring the cold south and low heights meeting Atlantic low pressure could easily result in rapid deepening and too much ne momentum against the flabby excuse for blocking . The ensemble mean is better thankfully but eventually one of these dodgy ops is going to start gathering more support . Sorry if this sounds underwhelming but I’m underwhelmed!

This is the models so far just for the easterly . Lowest values . GFS -10 UKMO -10 , a few localized -12 Arpege -10 ICON -8 GEM -10 I should advise caution for those in the se and south the cold pool is pretty small and in terms of any precipitation still a lot of uncertainty.

This is the models so far just for the easterly . Lowest values . GFS -10 UKMO -10 , a few localized -12 Arpege -10 ICON -8 GEM -10 I should advise caution for those in the se and south the cold pool is pretty small and in terms of any precipitation still a lot of uncertainty.

Putting aside the Greenland high drama . The UKMO has sub -10 850 crossing the south of the UK , the odd spot having -12 , T72 into T84 hrs . Still not convinced this is the end of the changes here . This would be the prime period for any convection , there’s not a lot of instability so the colder the 850s the better .

The shape of the block on the ICON 12 hrs run is similar to the ECM , also a similar set up towards the ne with the low .

So far the coldest 850 value moving west into the east se in relation to the easterly . Arpege -10 ICON -8

You don’t need some huge Greenland high to get cold into the UK . And you’d much rather have a smaller high which doesn’t head off west into the sunset .

The window of coldest uppers is brief and we need to see the 6 hour stages as it might have brought that through earlier . The depth of cold is still likely to change given the models seem to be making a drama over this .

We used to get model verification upto day ten . Can’t find that now but from memory it was generally around the 5 mark in terms of correlation. The ECM used to come out on top but not exactly world beating at that range. I should re-phrase that , it beat the other models but was still poor .

Before things turn ugly in here this morning ! Lets bear in mind the timeframes involved . If the outputs stopped at day ten re the GFS you’d think that was a decent chart . As for the GEM that’s admittedly not good at day ten but there’s going to be more changes . Let’s just wait and see what the ECM has on offer .

Earlier though there’s a large spread which is bizarre . Normally the strat forecasts are a lot less volatile at that range . As for the GFS 00hrs that looks like it’s gone a bit AWOL with the PV from hell to the nw .

Can I be blunt . The JMA is a garbage model. Really just ignore its ramblings regardless of what it shows .

God no ! Here it would be cold rain unless I head off to the Troodos Mountains. I’m happy to donate that outrageous cold pool to the UK .

The ECM does show some precipitation associated with that colder pool moving west . So likely it’s now seeing some convection . We don’t have a lot of instability so really need as colder 850s as possible . This chopping and changing re the depth of cold still has a way to go .

There’s also a deeper cold pool over Germany waiting to move west . You’ll see the ECM takes the nuisance shortwave ne and then absorbs it .

You know how obsessed I am with shortwaves! If the pattern ends up too far west it will be the broader pattern at fault . The issue with the ECM op is essentially the orientation of the block and position.

No west based negative NAO here so that’s good .

The nuisance shortwave isn’t a big deal in the grand scheme of things . It’s not a trigger shortwave . It’s only really relevant to the chances of getting some deeper cold in initially and a better chance of convection which is still limited by the lack of lower heights .