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

[Snowy L]

Easterly in at 72h

[bradymk]

ECM still the best of the big 3 at +72!

[AWD]

Just for balance, there are just as many milder members as there are colder ones in the medium to long range GEFS;

That's messier than my kids bedroom!

[Decemberof2010]

1 minute ago, AWD said:

Just for balance, there are just as many milder members as there are colder ones in the medium to long range GEFS;

That's messier than my kids bedroom!

Correct, a couple of horrors in there

[Frosty.]

A  generally cold GEFS 12z mean this evening beyond the next few days, some fantastically wintry perturbations in there, not much mild mush..hope the good news keeps coming!!

Don't let us down Ecm!

Edited February 17, 2018 by Frosty.

[WalsallWeather123]

47 minutes ago, Daniel* said:

I find it to be an odd observation to make when it’s the first I’ve seen which has pushed deep cold to north? And it’s a day 10 there is very little point in doing so. Overall broad pattern across the board is encouraging! 

The GFS at 240 hours shows a north south divide in temps. The precipitation chart was merely posted to show the difference in upper air temps. I didn't say the charts would verify. It was an additional post to back a point a previous poster had made

Edited February 17, 2018 by WalsallWeather123

[Met4Cast]

4 minutes ago, AWD said:

Just for balance, there are just as many milder members as there are colder ones in the medium to long range GEFS;

That's messier than my kids bedroom!

But interestingly, the cold members go seriously cold, that's probably the most ensembles we've had drop below -10c all winter

[bluearmy]

Ecm matters at T96/T120 to our west

the Atlantic put too much pressure on the block on the 00z run

[The Eagle]

ECM is broadly similar to the UKMO at 96 hrs

[Daniel*]

ECM continues to be more progressive fractionally more than GFS. Ground temps cooling nicely with severe frost and slack continental flow I don’t think it’s much different to 00z.

[The Eagle]

 

Still a little too much energy over the top.

[chris55]

1 hour ago, chionomaniac said:

What an amazing amount of cold right across Eurasia from Pacific to (almost) Atlantic coasts. Just shows how when the engine is turned off how the cold spreads southwards. Impressive.

 

Chiono, with all your efforts regarding SSW information/forecast techniques in recent years this must be a really exciting time for you from a viewpoint of SSW effects on the troposphere. 

We haven't seen an SSW for years and the science and model dynamics have progressed markedly since our last official SSW. Interesting times for sure  

[chionomaniac]

Because of the lack of comparison with identical timeframes it is difficult to say whether the ECM is better than the previous run or not  - so don't bother trying......

 

 

 

......I think it is a smidgeon better btw lol

[Ali1977]

4 minutes ago, The Eagle said:

 

Still a little too much energy over the top.

Mmmm, Im still not confident in a full on big freeze till the ECM changes (if it does), that large lump of PV lurking to our NW could pounce!! It’s still a nice 240 on the last ECM though to be fair.

Edited February 17, 2018 by Ali1977

[Catacol]

So - Saturday evening thought. Over the last week or so the models have generally been playing catch up in getting a handle on the tropospheric response to a major arctic warming and significant reversal. We are still seeing winds in reverse. Human interpretation has significantly led the way.

Are the models likely still to be playing catch up? Is it probable that all algorithms continue to overplay the normal westerly pattern, and undercook the speed of cold air advection westwards?

Id say yes - possible. Some of the more extreme runs on show may actually be more probable than we would normally expect to be the case, and rather than expecting a watering down of the process I wouldn’t be surprised to see a watering up - if you see what I mean.

Current mean forecast for the reversal sees it in operation until 1st March

 

Next warning phase directed at the Canadian vortex visible above and about to start. There will obviously be varying effects at different heights over this period, but I wouldn’t expect to see any resumption in dominant westerly forecasting for around a fortnight. We might actually see rather more in the way of upgrades rather than downgrades this time around.

Can’t quite believe my thinking is taking me down this path. 

[Daniel*]

To me this run looks better orientated to deliver them very cold uppers looking to east / northeast.

[cobbett]

6 minutes ago, AWD said:

Just for balance, there are just as many milder members as there are colder ones in the medium to long range GEFS;

That's messier than my kids bedroom!

The period 21-24  has the mean below -5  - the 6z was above. Quite a noticeable change at that range

[chionomaniac]

2 minutes ago, chris55 said:

Chiono, with all your efforts regarding SSW information/forecast techniques in recent years this must be a really exciting time for you from a viewpoint of SSW effects on the troposphere. 

We haven't seen an SSW for years and the science and model dynamics have progressed markedly since our last official SSW. Interesting times for sure  

Yes. I have been sitting back and watching it unfold tbh. The trop response is as I would expect from this type of SSW. Still a lottery as to whether we get that deep cold that we crave, but considering the years that I have put into monitoring the strat I love seeing these types of synoptics following the SSW.

[Weathizard]

ECM considerably worse than the GFS/UKM at the same juncture

[Daniel*]

Upgrade on the 00z much more cleaner I’d say for CAA.

 

[Decemberof2010]

1 minute ago, Weathizard said:

ECM considerably worse than the GFS/UKM at the same juncture

 

1 minute ago, Daniel* said:

Upgrade on the 00z much more cleaner I’d say for CAA.

 

Confused.com

[frosty ground]

2 minutes ago, Weathizard said:

ECM considerably worse than the GFS/UKM at the same juncture

 

1 minute ago, Daniel* said:

Upgrade on the 00z much more cleaner I’d say for CAA.

 

Hmmmmm

[eddy88888]

On 13/02/2018 at 16:38, Daniel* said:

Crikey AO forecast sheer vertical drop likewise NAO but not to that amplitude. 

wow so much snow on the way to southern england about time  its gona snow snow snow

[Weathizard]

Just now, frosty ground said:

 

Hmmmmm

It's marginally better than it's 0z but worse than the GFS/UKMO at the same time

[chionomaniac]

ECM improved though from it's earlier run. Look at the WAA to our NW to compare

12Z

0Z