Model output discussion - Post SSW - Will it turn cold?

[nick sussex]

What we’re trying to achieve here is the perfect balancing act.

The ECM manages to achieve that because it delays the trough dropping into Scandi by about 36 hrs.

But we do need that Scandi trough to prolong the cold and with it the blocking to the nw.

 

[Sawel]

Good ECM - it has much of the country in easterly winds for a couple of days whereas the GFS keeps the easterly going for 4 days for many parts. I guess I prefer the GFS output as a northerly doesn't excite me in the slightest!

 

[Daniel*]

Not even 2010 looks comparable.. For it to be knocking towards March it’s pretty extraordinary. No doubt the volume of cold we’re looking at is the result of the split, Eurasia frigid cold is highly correlative. 

Edited February 19, 2018 by Daniel*

[BLAST FROM THE PAST]

21 minutes ago, karlos1983 said:

We’ll have to settle for Northerly then 

Atlantic blocked for say about 5,000 km...........that should be ok....

 

BFTP

[yamkin]

7 minutes ago, nick sussex said:

As long as that happens after the deep cold has got in then it’s not a problem.

Its impossible to sustain the cold after the easterly without a blocking signal over Greenland .

See what happened to a few GFS runs with low pressure getting too far ne that’s the eventual outcome without the strong blocking signal to the n nw.

 

Exactly what I thought as well 

[Arrows1986]

Through your experiences what are the odds of a set up like this folding...or are the symnoptics that good that itll take alot for it to all go ...s up?

[snowice]

1 minute ago, BLAST FROM THE PAST said:

Atlantic blocked for say about 5,000 km...........that should be ok....

 

BFTP

Just had a look at ecm snow depths chart very impressive sorry can't post! 

[Summer Sun]

UKMO extended picking up a SE'ly flow shower activity begging to increase in the east

[BLAST FROM THE PAST]

2 minutes ago, Summer Sun said:

UKMO extended picking up a SE'ly flow shower activity begging to increase in the east

For Eastern half that looks like more Easterly to me?  Or probably beginning to turn Easterly

 

BFTP

Edited February 19, 2018 by BLAST FROM THE PAST

[Optimus Prime]

6 minutes ago, Daniel* said:

Not even 2010 looks comparable.. For it to be knocking towards March it’s pretty extraordinary. No doubt the volume of cold we’re looking at is the result of the split, Eurasia frigid cold is highly correlative. 

To be fair though the start of December is statistically quite a bit warmer than late February/early March.

Certainly though the air will be colder than in 2010. 

[AWD]

2 minutes ago, Summer Sun said:

UKMO extended picking up a SE'ly flow shower activity begging to increase in the east

Looks easterly rather than south easterly to me.

[Tim Bland]

Do we think the ECM is under estimating the convective snow potential? I expect the majority of the UK population would be wondering what all the fuss is about if this is the total snow depth at day 10? 

 

 

[phil nw.]

I am with you all and enjoying the outputs which we rarely see.

The ECM op tonight is a perfect illustration of what happens when the second warming wave pulses north and destroys the Canadian vortex -day 4 then by day 7 we see the pattern start to regress

later we see the evolution to a Greenland high so a bitter easterly by next Monday followed by a bitter Northerly later next week-you can't get much better.

Getting very interesting now ain't it?

Please though keep the ramping,gifs,BBC temps forecasts and assorted one liners to the right threads.We continue to remove off topic stuff which does get tiresome. I get the  excitement in some quarters but please save the team some work as well as keeping the thread sensible and informative for members and visitors alike.

Thanks all.

[Daniel*]

Saw this on twitter next Monday on ECM temps in the SE are 12C below the average I assume this would mean a daytime high of -3C even in London,  the level of cold not seen since 1991 - Europe frozen solid. 

Edited February 19, 2018 by Daniel*

[Guest]

Just now, Tim Bland said:

Do we think the ECM is under estimating the convective snow potential? I expect the majority of the UK population would be wondering what all the fuss is about if this is the total snow depth at day 10? 

 

 

We don't trust those charts even when we have a bit of snizzle in the forecast so I'm not putting much stock into them handling massive convective snow showers courtesy of the Beast itself.

Snow is notoriously hard to forecast at the best of times. Let's get the cold in and watch the instability do the rest!

[Deep Snow please]

4 minutes ago, Tim Bland said:

Do we think the ECM is under estimating the convective snow potential? I expect the majority of the UK population would be wondering what all the fuss is about if this is the total snow depth at day 10? 

 

 

Was just thinking that looking at it. Not all that severe snow wise.

All though a few perturbations give slightly deeper snowfall.

Going by past experience, almost certainly.

Edited February 19, 2018 by Deep Snow please

[SMU]

if ECM lands then 40-50cm widely over Kent 70-80 over the downs-

snow widespread elsewhere

East facing coasts - but streamers penetrating way inland also Ireland hit 30cm in an easterly the other year -

S

Edited February 19, 2018 by Steve Murr

[BlueHedgehog074]

It’s understandable that peoples’ excitement is snowballing regarding the Polar Express-esque outlooks and, as such, we’ve tried to be a bit more leaned back this evening with our moderating of posts in here. But just a friendly reminder that this is the Model Output thread and would appreciate any off-topicness to be kept to a minimum, or your post may not see daylight, again! Thanks a lot all and please continue  

Edited February 19, 2018 by DiagonalRedLine
Added extra detail

[jules216]

Liking the trend of the EC ops. for more -NAO amplitude of below -4, now that screams omega block to me, lets hope it stays firm as we know NAO can go awol, courtesy of some mysterious xxx solar flare out of nowhere knowing our luck

 

[snowice]

Just now, Deep Snow please said:

Was just thinking that looking at it. Not all that severe snow wise.

All though a few perturbations give slightly deeper snowfall.

 

in 2010 the snow went way inland. Ecm can only model what it's programed to do. I'd bet like in 2010 most of UK Ireland will be buried if Ec comes of.

[Summer Sun]

4 minutes ago, Steve Murr said:

if ECM lands then 40-50cm widely over Kent 70-80 over the downs-

snow widespread elsewhere

East facing coasts - but streamers penetrating way inland also Ireland hit 30cm in an easterly the other year -

S

ECM shows no more than 11cm for Kent area

[SMU]

Just now, Summer Sun said:

ECM shows no more than 11cm for Kent area

Model doesnt know convection rates.

Lake effect snow.

[ZK099]

Stunning charts but on a side note how bad has the ECM been! Usually considered top dog but it's been flip flopping all over the place with this cold spell. ICON stayed consistent and has impressed me, GFS also far more consistent than usual. Wonder what the ECM's been smoking this year 

[AWD]

EC 12z Mean charts are out;

 

 

 

T168 850hpa mean chart has -12c 850hpa temps clipping the south east coast;

 

Edited February 19, 2018 by AWD

[Doctor96]

I am 52 yrs and been watching the weather for over 40 yrs . When i was around 13 yrs in 1978 i remember the charts very well . we had a strong easterly around mid febraury  and max temp around -3 across a lot of UK. I lived in Newcastle and i recall blizzards like i have never seen. Newcastle was cut off from rest of country.  The models are showing charts identical to 1978 and this is the first time since 1978 i can recall seeing the same setup.  With the air crossing the north sea being so cold with a sea temp around 6 C , this will give us ice days , but the snow showers off the sea will become heavier through next week and east coast will look like armagedon. 

 

Truly i have waited 39 yrs to see this chart set up with the high over scandi and a low coming up from south.  Amazing that ECM has now followed the GFS and i am 90% certain members on here are about to see a historic event. 

 

Uppers of widespread -13 Will see minumums of -10 C all over and day maxs of < -2 C