Model output discussion - the beast arrives

[Singularity]

So... wow okay. Amazing how this low splitting away east and keeping it cold not just this weekend but we’ll beyond has kept on cropping up here and there yet not until now on the ECM.

Even stranger how it fits with the Met Office longer range talk of last weekend but not as well into their less cold for the south (than the forecasts were before) outlooks of late.

How can one low determine so ultimately where the polar boundary gets stuck next week as anomalies supporting the jet bejng at least a bit S of normal continue seeping down from the stratosphere?

Something stinks and it ain’t the snow; that’s still pure white here.

 

Good point regarding similarities to 2013 @CreweCold

Edited February 28, 2018 by Singularity

[Cheshire Freeze]

At day 9 we have little surface ridges popping up all over the show...

Discrete little features but enough just to deviate the flow. Reminds me very much of January 2013. If only it was 6 weeks earlier. 

It is very much a precursor to something showing up at short notice though...so don't be surprised if, over the next few days, the models take an unexpected twist or two.

Edited February 28, 2018 by CreweCold

[jayb1989]

Well, well, well.

Where has that ECM come from then.

Hopefully it’s onto something, however i would be suprised if it isn’t an outlier! 

[mb018538]

Some locations in Scotland are going to have metres of snow laying around for quite a while if the ecm verifies! Incredible run.

[Frosty.]

What a fantastic result for coldies the Ecm 12z would be..it would be absolutely amazing to think whatever snow has fallen or will fall in the coming days wouldn't thaw away across most of the uk!..really hope this run proves correct, there will be a lot of delighted coldies up and down the uk..fingers crossed!

[Purga]

22 minutes ago, nick sussex said:

JOY! 

The shortwave heading into the Channel  means energy is moving east rather than ne and this allows the UK to stay in the cold air , it also brings the chance of more snow as it heads towards Holland .

 

Actually Nick, both ECM & METO toyed with the shortwave idea a few runs back if you recall.

Let's hope this theme gets some legs with the other models!

Edited February 28, 2018 by Purga

[BlueHedgehog074]

3 minutes ago, Optimus Prime said:

Everyone seems surprised. Which is strange because ultimately what the ECM is showing is plausible given the background signals.

Plus, I think it was yesterday that the GEM 12Z showed something similar with Lows to our South-West disrupting enough to continue the cold Easterly flow over the whole U.K for next week.

[Youcan'tbecirrus]

1 minute ago, Purga said:

Acyually Nick, both ECM & METO toyed with the shortwave idea a few runs back if you recall.

Let's hope the idea gets some legs with the other models!

Totally at odds with the BBC then. London news just showing temps of around 9c starting next week so someone's got it badly wrong.

[Purga]

Yes, now all we need is a massive dump of snow tomorrow and Friday / Saturday to cover the whole country and keep the surface cold good and entrenched and we could be in for a nice bonus extra 10 days of cold and snow!

Edited February 28, 2018 by Purga

[jason75]

so if that shortwave moved east does that mean that low won't get as far north as forecast?

[chionomaniac]

Very very interesting ECM. More in tune with what I would expect. The effects of the SSW are unlikely to be blown away quickly imo. Now will the other models follow suit? A historic spell was forecast and that is what we were getting. I was in Liverpool in 87 and we got zilch snow - but that was still historic. 

So it looks like the 0ºC  850 isotherm may get as far north as the south coast but is quickly dissipated especially by the time the precip arrives in the south so really hoping that nowhere receives freezing rain.

 

Nice start to Spring anyway.

[chionomaniac]

1 minute ago, jason75 said:

so if that shortwave moved east does that mean that low won't get as far north as forecast?

Yes. It is a balancing act between keeping the cold and maximising the snow chances and there is a trade off in the middle

[icedust]

Model chaos indeed.

ECMWF, EURO4 and GFS are all predicting 850 temps above zero edging in to the SW and far south of England at around T+ 42 to T+48

 

 

. BUT at the same time the surface and 950mb temps well BELOW zero.:

 

 

This is a forecasters' nightmare and could be (as our North American friends say) an 'ice storm' or freezing rain. It depends how deep that warm nose is forecast to be whether the snow melts into rain  as it falls through this nose.

Luckily all is back to some sort of normal by T+54 (by T+72 for ECMWF due to its only 24h read-outs)with all levels sub zero again and back to snow.  This is model prediction and may not come to fruition, let's hope so.

 

[Summer Sun]

The GFS 12z London mean shows a recovery in temps for the south through the weekend as less cold air moves up from the south

This less cold air lasts through to around mid next week beyond this slightly colder air returns with the mean peaking at a low of around -4 around the 8th and 12z

Further north the recovery is slower with Edinburgh going from -15 850's today to -5 on Monday a slight drop is possible again around midweek to about -6 before a slow rise through to mid-month

[Methuselah]

2 minutes ago, chionomaniac said:

Yes. It is a balancing act between keeping the cold and maximising the snow chances and there is a trade off in the middle

Apart from in 1986, it's what happened in most of the prolonged cold, snowy spells I can remember, chio. I don't think I can ever remember a lone depression take the route forecast for this one, at least during blocked scenarios such as this one...? The again, there's a first-time for everything.

[Tim Bland]

I remain sceptical of the ECM when none of the above GFS ensembles show anything similar. For now it’s definitely the outsider, will be amazed if it is support from its ensembles later! Let’s pray it is a new trend! 

[BLAST FROM THE PAST]

27 minutes ago, Essex Boy said:

Incredible performance from the ECM. Expectations should be managed though. As someone said, it would surprise me if the ECM were the first model to pick up on the overwhelming cold retention. Don’t get me wrong I’m excited as much as the next person but more verification is required. I rarely post but the model watching and twist and turns of late has been truly fascinating. 

First?  It’s been touted ??.  What a great run.....could this be the start?

 

BFTP

[Purga]

Look at the latest fax chart showing the front much further south than the earlier one for the same time

Latest                                                            Earlier

Good if you want to prolong the cold!

 

Edited February 28, 2018 by Purga

[Optimus Prime]

The indication from the ECM is the UK, NW Europe, Eurasia, Russia and Siberia will remain unusually cold for the time of year:

The reversal in winds will probably see out the first ten days of March. 

[SMU]

7 minutes ago, chionomaniac said:

Yes. It is a balancing act between keeping the cold and maximising the snow chances and there is a trade off in the middle

I cant remember if I posted in here or the SE thread however the models have continually reduced the northern extent of Fridays front - so with every run where a model fans the energy East in stead of North - so the front stalls & straddles The midlands & SE for longer

It was only a matter of time before the models - notably the ECM moved so much energy East that we closed off the low & allow it to send the cold back south-

The next 3 days could deliver batches of frontal snow for many areas ....

Looks Good to me...

S

[nick sussex]

10 minutes ago, Tim Bland said:

I remain sceptical of the ECM when none of the above GFS ensembles show anything similar. For now it’s definitely the outsider, will be amazed if it is support from its ensembles later! Let’s pray it is a new trend! 

Not to worry the JMA has some support for the ECM op! 

Seriously though the shortwave is so important that if the GEFS ensembles are wrong re that then you can throw the lot out .

It’s best to be sceptical though as it’s just one run and we need the others to move quickly towards the ECM given the timeframes.

Edited February 28, 2018 by nick sussex

[high ground birmingham]

If I am not mistaken, the GEM was touting this idea for quite some time. The ECM has picked up this signal. Would be incredible if it came off and a massive coup for the GEM

[Spurry]

Can't believe tonights ECM 12z , very good for more central and northern areas ,keeping the cold locked in beyond the weekend and well into next week.

[BLAST FROM THE PAST]

2 minutes ago, Steve Murr said:

I cant remember if I posted in here or the SE thread however the models have continually reduced the northern extent of Fridays front - so with every run where a model fans the energy East in stead of North - so the front stalls & straddles The midlands & SE for longer

It was only a matter of time before the models - notably the ECM moved so much energy East that we closed off the low & allow it to send the cold back south-

The next 3 days could deliver batches of frontal snow for many areas ....

Looks Good to me...

S

Agreed Steve....looks good AND feasible

 

NFTP

[Summer Sun]

UKMO extended remaining unsettled into next week