Model Output Discussions 18z 31/01/2016

[nick sussex]

2 minutes ago, Man With Beard said:

UKMO T144 could lead to a very cold NEly by T192 - air all the way from above Norway will get on the top flank of the Atlantic low, which itself looks set to drop over us in later frames

Preferably we want that low to drop se not south, its important to have any Euro troughing sufficiently east to stop milder air from the Med being pulled nw into the circulation. We also want that deep low over the eastern USA to engage that PV lobe and pull this further west.

Looking at todays MJO update the time is now! if we don't see some good charts appearing in the next few days then its not going to happen because the ECM in particular has sped up the movement towards phase 8.

 

[Daniel*]

Quite frustrating synoptics which don't look bad on the eye sums up this winter; parameters are just not conducive for snowfall, we get the entrails of cold air - which is generally fleeting, more cold rain for Southern England based on this for midweek and I doubt the UKMO would be dissimilar. 

[Cloud 10]

The GEM at 96 hrs looking very UKMO'ish.

 

[chrisbell-nottheweatherman]

6 minutes ago, Daniel* said:

Quite frustrating synoptics which don't look bad on the eye sums up this winter; parameters are just not conducive for snowfall, we get the entrails of cold air - which is generally fleeting, more cold rain for Southern England based on this for midweek and I doubt the UKMO would be dissimilar. 

True, though that's a touch IMBY given that large parts of the UK are forecast to have negative dewpoints - even as far south as my location, it's showing -1/-2C DPs.

Edited February 19, 2016 by chrisbell-nottheweatherman

[Severe Siberian icy blast]

If this wasn't after a 3rd dire winter on the trot then this place would be buzzing .

Big differences between the 06/12z so have to mindful of that although the 06z has always struggled with blocking . But looking very interesting moving forward and early March would easily bring lying snow .

[Singularity]

Yep the MJO has hit phase 7 at much higher amplitude than the models were going for... that ought to shake things up really!

GFS is remarkable in how unlucky it has us being; the runner to the south matures prior to arriving yet the fronts don't occlude sufficiently to produce snowfall (but that does seem a bit suspect...?), and then we have a big dig south of the jet but this time too far west with the trough ending up SW then S of the UK, which makes it hard to get sufficient cold air into the mix given the lack of a deep cold pool over the near continent.

 

Some hope going forward to be taken from the big reduction in how fast LP moves up the Eastern Seaboard to engage with the Canadian cold pool on this run:

12z  06z   

...but it still manages to annihilate what is a decent ridge through Greenland from the Atlantic, despite that feature having longer to gain strength... and once again the model us unable to recover the situation thereafter as the usual bias feeds back into the system. We are being robbed of a lot of should-be long-range eye candy at the moment!

All that despite the strat. vortex displacing nicely and then dying a death.

  

If I could punch GFS in the face... okay I had better stop typing now!

[Man With Beard]

53 minutes ago, Daniel* said:

Quite frustrating synoptics which don't look bad on the eye sums up this winter; parameters are just not conducive for snowfall, we get the entrails of cold air - which is generally fleeting, more cold rain for Southern England based on this for midweek and I doubt the UKMO would be dissimilar. 

In all honesty, having studied the charts tonight, I'd expect plenty of snowfall for the north of England and Scotland next week. Midlands might scrape the barrel, but as you rightly say, not a lot of hope for snow for the southern quarter of the UK unless something like the UKMO verifies and the trough falls into Europe in a favourable manner.

[winterof79]

46 minutes ago, chrisbell-nottheweatherman said:

True, though that's a touch IMBY given that large parts of the UK are forecast to have negative dewpoints - even as far south as my location, it's showing -1/-2C DPs.

Here's the "forecasted" precipitation chart for that time frame.I am trying to understand how people are getting excited by average charts.

 

[bobbydog]

51 minutes ago, chrisbell-nottheweatherman said:

True, though that's a touch IMBY given that large parts of the UK are forecast to have negative dewpoints - even as far south as my location, it's showing -1/-2C DPs.

you're saying its imby because daniel mentioned southern england. yet he's actually correct. cold rain for southern england, virtually nothing further north-

[winterof79]

4 minutes ago, Man With Beard said:

In all honesty, having studied the charts tonight, I'd expect plenty of snowfall for the north of England and Scotland next week. Midlands might scrape the barrel, but as you rightly say, not a lot of hope for snow for the southern quarter of the UK unless something like the UKMO verifies and the trough falls into Europe in a favourable manner.

Could you please explain a little more as I don't see this in the charts I can see.There is a lack of precipitation and what there is is rain apart from the far North of the UK.

[Paul]

7 minutes ago, winterof79 said:

Could you please explain a little more as I don't see this in the charts I can see.There is a lack of precipitation and what there is is rain apart from the far North of the UK.

Not wanting to put words in MWB's mouth, but it would depend which part of the week you're looking at. For instance (and these are just raw GFS snow accumulation maps so not to be taken literally):

Friday morning:

Saturday:

Obviously, it's one run from one model, and way off so bound to change, but at face value there is lying snow shown in Scotland, Northern England, North Wales and maybe scraping the north Midlands next week. 

[IDO]

6 minutes ago, winterof79 said:

Here's the "forecasted" precipitation chart for that time frame.I am trying to understand how people are getting excited by average charts.

 

Yes I though I missed something. For the south close to average temps with the best ENS support for snow at 15% at any given chart:

Despite the GFS moving closer to the ECM, it unlike the ever over optimistic ECM, has rather meh uppers, and if you look at the mean uppers anomaly it is pretty close to average throughout (after the mild spell this weekend): http://www.meteociel.fr/modeles/gefs_cartes.php?code=21&ech=6&carte=0&mode=6

So yes I agree on the current GFS run (of course changes may happen), it is just seasonal stuff, no unseasonal cold and no snowfest inbound. The GEM is better for a bit colder uppers but again that is not reliable and I haven't seen its ensembles yet.

[IDO]

2 minutes ago, Paul said:

Not wanting to put words in MWB's mouth, but it would depend which part of the week you're looking at. For instance (and these are just raw GFS snow accumulation maps so not to be taken literally):

Friday morning:

Saturday:

Obviously, it's one run from one model, and way off so bound to change, but there is snow shown in Scotland, Northern England, North Wales and maybe scraping the north Midlands next week. 

Hi

That is above sea-level, is that meters above or feet above? That looks like hills and mountains to me.

[winterof79]

1 minute ago, Paul said:

Not wanting to put words in MWB's mouth, but it would depend which part of the week you're looking at. For instance (and these are just raw GFS snow accumulation maps so not to be taken literally):

Friday morning:

Saturday:

Obviously, it's one run from one model, and way off so bound to change, but there is snow shown in Scotland, Northern England, North Wales and maybe scraping the north Midlands next week. 

okay,FAR Northern England as I class myself as Northern England.The Same charts that had us under inches of snow earlier this week,as you say not to be taken literally.

[Gowon]

The arpege comes up with a different solution with the low further south.

snow risk again for most of the country next tues/weds.

I think we can expect more changes. 

[Carl46Wrexham]

7 minutes ago, Vivian said:

The arpege comes up with a different solution with the low further south.

snow risk again for most of the country next tues/weds.

I think we can expect more changes. 

If I had a fiver for the number of ARPEGE charts I've seen over the course of this month, all of which have shown snow, and all of which have turned out to be completely wrong.....

not convinced anymore...sorry. Fool me once.....

[winterof79]

10 minutes ago, Vivian said:

The arpege comes up with a different solution with the low further south.

snow risk again for most of the country next tues/weds.

I think we can expect more changes. 

Thanks for that.Interested to see ECM later and the track of disturbances.Hopefully more of the UK can get into the mix.

[Spah1]

3 minutes ago, Carl46Wrexham said:

If I had a fiver for the number of ARPEGE charts I've seen over the course of this month, all of which have shown snow, and all of which have turned out to be completely wrong.....

not convinced anymore...sorry. Fool me once.....

Couldn't agree more. Those snow charts are as useful as an inflatable dartboard. 

[Gowon]

1 minute ago, Carl46Wrexham said:

If I had a fiver for the number of ARPEGE charts I've seen over the course of this month, all of which have shown snow, and all of which have turned out to be completely wrong.....

not convinced anymore...sorry. Fool me once.....

I know, I'm frustrated too, but i'm just showing there's still a possibility.. 

[Gowon]

Nice ecm 120 with the whole country under -8/-10 air

[Lukesluckybunch]

7 minutes ago, Vivian said:

Nice ecm 120 with the whole country under -8/-10 air

Well it's even better at 144!

[Gowon]

and an even better 144

cold air building up to our east too!

[Cloud 10]

ECM is a stonker this evening,and could get even better!

 

168hrs

 

 

[bluearmy]

Pretty snowy ecm op

a light covering in the south into tues am

a disturbance coming down from the nw day 6

the occlusion headed in day 7

expect detail to change by the morning but this does look like disruption into colder air than we just had so better opportunities for snowfall 

[Daniel*]

Wednesday will need to be watched closely with a southerly tracking low pressure system engaging with cold air. 

Bitter Thursday with HLB more abundant on this run I think this is going to turn out to be a 'Stella run'.

 

Edited February 19, 2016 by Daniel*