Model Output Discussion - Spring Has Sprung

[Ali1977]

The lesser models are all good day 10-12 

[ICE COLD]

The ECM control is turning into a cracker .

[Mike Poole]

The low at T120 is really causing the models some issues, probably because on some runs it splits into more than one  low.  My view when I looked at the clusters was that the UKMO solution should not be discounted, and here’s a handful of the EPS that show a more southerly track:

Edited February 4 by Mike Poole

[ICE COLD]

It getting even better

[nick sussex]

The GFS 18 hrs run is tedious .

After some frontal snow for the north the cold is blown away with the limpet low just slowly filling and heading north .

I’m fast losing patience with the outputs . 

Can we just get to the blocking !

[IDO]

The GFS 18z is not cold for the UK after the mid-week frontal event moving north. At the end of the week, cold and snow never materialises. D7 :

It was just one run, so I would not take it seriously unless repeated, but it was a big turnaround from what the models showed a few days ago.

Edited February 4 by IDO

[nick sussex]

The limpet low effects the UK for 6 days . Jeez enough already ! 

 

[ICE COLD]

 nick sussex yep terrible 18z let’s just hope the ECM control is on the right lines . The ECM mean is pretty decent aswell for so far out . 

[sheikhy]

Arpege further south again!!

[Battleground Snow]

Just the 150 mile difference on the arpege and gfs at 102 hours.

Those of us that have been around for many years, know that the gfs 18z run is not going to happen, the way the low just sits there for days.

 

Edited February 4 by Battleground Snow

[damianslaw]

GFS18z up to its bizarre best, sends the low pressure north for duration of about 5 days..

[nick sussex]

The limpet low arrives in the sw at T96 hrs. It hangs around the UK and then travels north before then shifting slightly further south at T294 hrs and then finally gets absorbed by another Atlantic low at T306 hrs !

It manages to ensure that the high pressure belt to the north doesn’t advect any cold into the UK .

The low will now be re-named the Spawn of Satan Low ! 

[Battleground Snow]

For what it's worth, 18z gem has adjusted south at 84 and 18z ukmo looks very similar to it's 12z position at 66

Edited February 4 by Battleground Snow

[Rain All Night]

9 hours ago, RainAllNight said:

0z/6z deterministic runs, Sun 4th to Sun 11th (day 7)

Contrary to my previous assessment, the models have continued to offer some hope of the "big low" delivering snow further south than Scotland (other members have posted short range 6z model outputs offering us updates on this situation), and as the selection of runs presented below illustrate, there may be further opportunities for various locations later on during the low's journey over the UK. By day 7, the next low coming in from the Atlantic has a very southerly track, and is being squashed and hindered by high pressure to its east and/or north.

0z/6z ensemble means, Sun 4th to Mon 19th (day 15)

There remains agreement on high pressure building over the UK once the "big low" has passed. There is also agreement that this will gradually migrate to the west, and possibly to the northwest. This gives us the impression that Atlantic lows will be blocked from reaching us again for quite some time. There is even a hint, on the GFS and GEM ensembles in particular, that some low heights may be able to approach us from the northeast late in the run, which would open up support for some very interesting winter weather scenarios.

The wind roses on this ECM ensemble meteogram for the south coast show us in simple terms the pattern change that is approaching.

Two hours later than I would have liked to have posted this, owing to the ECM ensemble taking much longer than usual to load in full on Meteociel...

12z deterministic runs, Mon 5th to Sun 11th (day 7)

We still have the torment of just one or two models teasing with the possibility of a more ideal shape to the "big low" when it first arrives on our shores later this week. Beyond that, we have the interest of whether any meaningful troughing will form downstream over Europe, and what will happen to the high pressure that is being pushed along towards us by the next Atlantic low.

12z ensemble means, Mon 5th to Mon 19th (day 15)

ECM has a noticeably different flavour to the other two models this afternoon, with the low heights associated with the "big low" taking longer to clear the UK and be replaced by high pressure, and then showing lower mean heights to our south and west later on; nonetheless, the Atlantic is still blocked at the end of the run. ECM also has a better and more prolonged mean easterly for Scotland during the passage of the "big low" itself.

Edited February 4 by RainAllNight

[feb1991blizzard]

7 minutes ago, nick sussex said:

It manages to ensure that the high pressure belt to the north doesn’t advect any cold into the UK .

That is what you call a North based -NAO!

[Purga]

So far FI, we'll either end up with a BFTE or a wretched Bartlett - take your pick!

Knowing our luck, all of Europe will go into the freezer with copius snow and we'll be left in the ueber mild crud - you couldn't make it up

[SLEETY]

gfs op was one of the warmest runs in the pack for most of europe nevermind the uk,its lost the plot again

some of the ensemble runs were over 15c colder than the op.london and brussels below

Edited February 5 by SLEETY

[Lukesluckybunch]

Nice ICON run..!low further south pulling in cold air by Friday..180 looks setting up for a lengthy cold spell

Edited February 5 by Lukesluckybunch
Adding

[feb1991blizzard]

UKMO 72 pukka

Edited February 5 by feb1991blizzard

[Lukesluckybunch]

1 minute ago, feb1991blizzard said:

UKMO 72 pukka

You like that feb?better then gfs!gem looks ok too!

[Ali1977]

T98 UKMO

[Lukesluckybunch]

96h ukmo

[Mike Poole]

I think the flatter, more disrupted low (and therefore more southerly) is winning out here - as I mentioned last night, the EPS did have support for it.  And if that is the case, one would expect GFS to be last to go with it, as it does have a bias towards blowing up lows rather than sliding them, which is kind of what we’re seeing.  

[Lukesluckybunch]

Gfs looks to be on its own a real mess...ukmo brilliant!

[Ali1977]

UKMO is that even further south than its last run ️