Model Output Discussion - Spring Has Sprung

[IDO]

The UKMO completes its three-point turn and is now closer to what GFS/GEM/EC was showing for the weekend:

Despite days of runs pushing the cold south, it was the last to correct it to the above. I mention this as an IMBY for the South. Those south of M4 probably miss out totally on the fun.

GFS op is interesting with Event 1 as it moves towards yesterday's EC 0z of a stalling front as it hits the cold:

Looking at members, this remains fluid as the low position, angle, and longitude all affect this outcome. This explains why ensembles are all over the place. So, confidence is middling as to extent and longevity (for some), but higher ground could take a pounding if there is stalling. EC is not as good as GFS, though. It and the UKMO are the worst for the snow to melt quickly:

Day 4 EC: 

Post-D7, it looks like height rises from Iberia. The means at D9:

Maybe a weak mean Scandi surface high develops for a short while after D9, but no solid easterly, and any cold air is too far east, and it has a weak flow as the mean high slips south later in the run (T300+). It is early days on post-D7 as we are still ironing out the finer details of the following week. So expect changes, though the means have been confident of UK height rises for days for that period. But the GEM op shows the model's struggles:

 

Edited February 6 by IDO

[MattStoke]

 Ali1977 That’s Monday’s UKV. Here is today’s.

[Ali1977]

 MattStoke bugger, good for your location though I’ll just have to hope the Arpege has it 

Fax looks a little better 

Edited February 6 by Ali1977

[Dennis]

easterlies may setup from the weekend 

[daz_4]

Easterly may setup but there is no cold air over Europe and the high over Russia is keeping it far away to east.

[Drifter]

Probable snow in the SE from ECM at, you guessed it - day 10. 

Edited February 6 by Drifter

[Ali1977]

Fax charts have kept the front further south fir Friday too 

Looks good 

[carinthian]

Morning all from another clear frost free morning +5c at 0600t.  Thinking about how all the models have performed this week , these words come to mind " Oh what a tangle web we weave " ! All this week the GFS  op runs have blown up the approaching low into the British Isles and have been warm side of the mean. Now the lastest run backed by the  mean starts to sink the low into Europe by the end of the weekend. This was earlier the trend shown on UKMO model , which over the past 24 hours has now moved the low north. You cannot make this up ! I think it is quite possible we could start to see a quicker transition into an Easterly for your latitude ( oh , not again , thinking leading up the garden path ) but I now expect to see this low start to slowly sink in the coming runs as the upper pattern alignment is more favourably for a cold outcome acrossthe British Isles.  The Super HD 4x4  snow model results will be available soon and I will let you get a update for The British Isles when I have the see the feed provided. In the meanwhile a bit of sun bathing on the agenda today over here .

C

[Climate Man]

 daz_4 probably low enough 850s early on for a little snow and then perfectly possible for a local cold pool to hang on and build in that flow. 10 days away may as well be a month currently though.

[Singularity]

I think we’re being reminded what happens when the usual westerlies take a vacation - the model accuracy drops substantially.

For what it’s worth, runs that lift the low well to the N or even NW during this weekend look pretty bizarre against historical precedent - usually when there’s a trough over Scandinavia, the low either stays at a similar latitude or heads southeast. Yet we have some model runs suggesting that a small low to the northwest becomes the dominant ‘anchor point’ around which the low over the UK moves. I suppose it must be plausible but seriously unusual nonetheless.

How it pans out has implications for next week too, although typical model bias seems more influential by then. GFS throwing overly broad and progressive lows at a high over Scandinavia, now there’s a familiar story.

[winterof79]

Blocked End of Feb and March incoming 

[bluearmy]

8 hours ago, ICE COLD said:

e NH in , no matter what it just doesn’t fall are way . Just can’t see it happening now . Even the GEFS have gone the wrong way in FI and the ECM ens hardly look great. So that’s up to the 20th and then we’re obviously fighting an even more up hill struggle with it being so late . Maybe next year

I wouldn’t disagree with you 

I’m also struggling to see strong evidence that the macro pattern will align itself to bring deep cold to our shores. Post mid feb we need quite specific alignment on the flows or v low 850’s for areas away from elevation to bring conditions that would satisfy the majority here. 

the ens are pointing strongly towards height rise to nw in week 2 and an undercutting by the Atlantic lw trough. But you’d bet that the likely consequence of that will be a lift of some kind in euro heights which will certainly put the southern half U.K. in the less cold air fairly quickly. Of course that could well mean a decent number of people here are in the battle zone so I shouldn’t be imby about it. But given that we will then be into the last half of feb and the further north the battle zone is the longer the sea track of flow ahead of it, I’m not sure that’s so great away from higher ground either. 

we are still looking at the nwp feeling it’s way to those height rises so we shouldn’t discount a route from left field that does bring the desired uppers but for now it’s a tough watch. 

[bluearmy]

 Ali1977 Fri fax is currently updating Ali ?  You’ve posted yesterdays run for thurs as T84

 

Edited February 6 by bluearmy

[Dennis]

Ireland /Uk thursday

[mulzy]

 Drifter Cold drizzle - 850s not low enough.

[Uncertainty]

The eps builds the high further to the NE, not so much a U.K. high anymore @IDO ? This high seems rooted over scandi. Last night’s eps was more a northerly Sceuro.

Its not a BFTE yet, but it’s an improvement towards a cold fetch easterly…

[Lukesluckybunch]

3 minutes ago, Uncertainty said:

Its not a BFTE yet, but it’s an improvement towards a cold fetch easterly…

 

Not bad for a mean!

[Marting]

ECM ensembles showing a fairly cold picture out to day 15. Winds turning easterly and the maybe north eastern later

[sebastiaan1973]

Average at 240h. EC. Impressive. 

[CoventryWeather]

Good morning, 

Still plenty of uncertainty regarding the low, ensembles pretty much the way to look. 

Not going to say much but quick looks did seem to suggest they moved slightly further south this morning, so more of the mids see a decent day of snow cover (Thursday). 

With regards to a more southern shift again, the WRF model (which was consistent on a rather northerly path) has significantly shifted south compared to recent runs. 

But mid term still seems decent - perhaps an Easterly past mid month so let's see if that comes to anything. 

[IDO]

 Uncertainty

That is not my preferred outlook at D10 EC mean:

Caught between the Atlantic and the Siberian High. Another 10+ days gone for potential snow. IMHO, a Siberian mean high is not what we want. Usually means continental (SE) air and Europe is not that cold. The UK still under the auspice of high pressure with a rampant Iberian ridge. A UK high would have more likely led to retrogression to Greenland and a much quicker route to cold/snow. But ATM, and I would stress that bearing in mind the model's performances of late, it looks like settled and cool as we move into the last half of Feb (EC).

So, hoping EC mean is wrong. FWIW the EC op is an outlier at D9+ on all three metrics; eg:

Confirming my earlier thoughts that the ops are struggling and that may even be reflected in the means.

[AO-]

 Drifter

I think there won't be snow. I think the temperature (up at 500mb level) is too high plus an easterly flow. Too little time to generate snow (showers). Pressure is rather high. But those are details at that timeframe. 

Edited February 6 by AO-

[Dennis]

i think all starts from 12-14th

 

Edited February 6 by Dennis

[AO-]

 sebastiaan1973

Yes, it certainly is. If only there is cold available. Of that I'm not so sure. Mild air is sent towards the Russian border. 

 

[Lukesluckybunch]

Its now looking increasingly likely it could turn quite wintery next week!ecm op and gefs mean..now showing this with a east/northeast flow setting in!..if i had to guess I would say it's about a 60% chance at the moment..it's another day 10 chase but that's the way it is in the uk!

Edited February 6 by Lukesluckybunch
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