Model Output Discussion - Spring Has Sprung

[Eskimo]

So it's pretty much 

ECM & UKMO v GFS, GEM, ARPEGE & ICON

...in terms of that initial front sliding through. 

[feb1991blizzard]

 nick sussex

No - if anything its worse, snow / rain boundary further North.

[Captain Shortwave]

Late next week looks very delicate and very small differences can determine whether the low deepens towards the UK or runs through the channel as a shallow feature. The UKMO keeps the low separated from the main troughing which allows a much more southerly track, the GFS on the 06z not only connects the low but the cold pooling from Scandinavia connects to the PV moving towards Greenland at the time which seems to slow the low even further and deepen in situ as there is a gap to pull WAA ahead of the low over the UK, hence the snow to rain event.

I wouldn’t place my money on either option yet to be honest.

GFS

Hard to spot but you can see the embedded troughing within that low extending out of Greenland.

UKMO

 

Much less pronounced and a more elongated and complex system. You could argue that the GFS is potentially over simplifying the set up into that one low when the reality could be a series of small systems that will gradually break eastwards.

 

Edited February 5 by Captain Shortwave

[Lukesluckybunch]

Good consistency from the gfs,it's trying it's best to make the whole UK mild! We should possibly be worried

[sheikhy]

 Battleground Snow i would have to go with gfs man as hard it is for us snow lovers!!!!ecm been all over the shop this winter which is my go to model normally!!gfs has been rock solid with this so far!!!!!

[MKN]

Gfs remaining consistent with snow mainly reserved for high ground across England and Wales. Snow for many in Scotland. Past history usually favours GFS in these type of scenarios at this range. Hopefully it's got this one wrong

[Lukesluckybunch]

A very bad run from gfs!how can it be so different from ukmo!identical to its 0z run

Edited February 5 by Lukesluckybunch
Adding

[Battleground Snow]

 sheikhy

Met office gone very early on a warning, sounds like they expect something quite disruptive.

Gfs does like to blow up lows in the Atlantic, it's probably it's biggest weakness.

Arpege out in 15 mins.....

Edited February 5 by Battleground Snow

[Spah1]

 MKN Past history favours GFS? Absolute waffle. 

[sheikhy]

 Battleground Snow yes we have the comfort of knowing that gfs can and has been wrong at just 48 or 72 hours out before!lets hope this is one of those moments!!!

[nick sussex]

The GFS delivers the worst possible solution from the set up.

It blows the cold air away from the UK and from most of mainland Europe.

Dreadful stuff . If this verifies against the Euros at just day 4 meaning they’re both wrong then I think it’s time to call time on this winter .

Edited February 5 by nick sussex

[Mike Poole]

 sheikhy I think it has been rock solid because it is erring on the side of its known bias to blow up lows, rather than disrupt them.  The fact that the other models are seeing a shallower feature should not be discounted, I think it is likely that they are right and GFS has it wrong.

[Drifter]

GFS - the winter killer run. Just wasting everyone’s time if that synoptic sets up. 

[MKN]

 Spah1 Given GFS has historically called marginal situations correctly more so than the other main models I would say it's not waffle. I've followed these charts for over 20 years and this sort of setup favours the GFS solution. Of course your own locality may sway your judgement on that particularly if your further North but for Leicestershire when the gfs has predicted rain or sleet with other models suggesting snow then I've found it's nearly always been rain we end up with.

[Drifter]

 Battleground Snow

Up to 2cm on lower ground, then turning to rain. 

Doesn't sound too disruptive unfortunately.

[Djdazzle]

 nick sussex I called time on this winter several weeks ago. Despite promising synoptics and background signals, something always goes wrong.

GFS aside, there are more ways of snow not happening at the end of the week than vice-versa.

If we do get anything wintry, see it as a huge bonus.

[IDO]

 Battleground Snow  All models have agreed on some snow on Thursday as the front moves north, even the GFS! Which shows this:

So, it's not a surprise a warning has been issued. They did add "uncertainty", "turning to rain", and the "boundary", all things that we have been mulling over. I hope we get the best-case scenario.

[nick sussex]

The issue with the GFS is that it’s shown absolutely no sign of any backtrack . Indeed it’s even worse which makes a possible middle ground solution underwhelming.

We really needed it to start moving . 

It really is last chance saloon time this evening .

[Ice Day]

GFS, UKMO, ECM, GEM at 138/144

   

It's really a 1 in a 100 shot that the GFS has it right and the others wrong at this range (probably 1 in a 1000).  As @nick sussex says above, if it is correct I think we should in future bin all output beyond 72 hours! 

[MattStoke]

GFS is always the worst performing model in this situations. Doesn't mean it's definitely wrong this time but it doesn't give one much confidence in it's output.

[danm]

 AltonMatthew Sort of agree, I have never been able to get myself excited for a snow to rain event. It may be nice while it lasts but if it's washed away in a matter of hours I tend to think what's the point. 

The main interest currently lies beyond that. 

[Drifter]

 Ice Day Don’t forget the golden rule is that whatever run is worst for UK cold is the one that verifies!

[Spah1]

The GFS runs at lower resolution. Exeter have just put out a warning based on their short range models not the GFS. So the MO are wrong 3 days out and the GFS is right??

[Lukesluckybunch]

High of 8c was showing my area thrursday..now it's down to 6c with sleet forecast...something is brewing

[topo]

Not THAT different from GEM though at 180 hours..