model discussion Model output discussion - closing in on Winter

[IDO]

Looking at last year when we had similar background signals, we would expect, after a trop-led Atlantic block, a rush as the tPV is released from the blocking pattern. Maybe 5-7 days and then a return to HP to the SW, maybe more UK centric until we get another trop driven driver for Atlantic heights.

That is assuming the strat-trop disconnect remains the status quo. GFS had for a couple of days made much of a Pacific wave, maybe in response to the MJO signal, but again we know from last year the MJO never really drove the weather as the composites suggested, so this morning that signal has been lost, at least on the 0z.

The LR forecasts are a bit meh but this cold spell suggests with a good alignment we could still get the occasional cold, and hopefully as per last year, a strat event sometime in February?

Edited November 25, 2021 by IDO

[northwestsnow]

51 minutes ago, SLEETY said:

You know when things look grim again for cold when people start posting charts from 47,87 etc

December in UK is rarely a bitter month anyway,coldest weather seems to be right at the end of the winter, rarely at the beginning. 

The last paragraph is certainly true .

OK,as expected the pattern will flatten out ,so coupled with Exeters swing to a zonal outlook  yesterday one naturally would be inclined to ' fear the worst ' ...

the day 10 mean is of course classic +NAO but there is no Euro high at this juncture .

It's difficult to see a way of avoiding a period of Atlantic weather in the medium term, i guess its a case of wait and see as to the duration.

[Premiere Neige]

45 minutes ago, IDO said:

Looking at last year when we had similar background signals, we would expect, after a trop-led Atlantic block, a rush as the tPV is released from the blocking pattern. Maybe 5-7 days and then a return to HP to the SW, maybe more UK centric until we get another trop driven driver for Atlantic heights.

That is assuming the strat-trop disconnect remains the status quo. GFS had for a couple of days made much of a Pacific wave, maybe in response to the MJO signal, but again we know from last year the MJO never really drove the weather as the composites suggested, so this morning that signal has been lost, at least on the 0z.

The LR forecasts are a bit meh but this cold spell suggests with a good alignment we could still get the occasional cold, and hopefully as per last year, a strat event sometime in 

I believe both GFS and ECM were forecasting a potentially substantial warming as early as week commencing 6th December earlier this week. Hopefully it's still there whenever the next update is (I believe for one of those models it's today but not sure which).

[Anthony Burden]

Morning all,GFS /ECM blowing in from a west to northwest temperatures more around average into

first week of December nothing mild Gefs showing an average period coming up also.

The Azores high never to far away with some ridging into mid Atlantic keeping west/northwest flow

going.Waiting to see if Atlantic takes complete charge or a pressure rise occurs hopefully to our

northwest/northeast.

[sheikhy]

Hmmm gfs seems to have snow for eastern england for a good number of hours on the 06z for saturday!cant it push further west though?!

[damianslaw]

8 minutes ago, Anthony Burden said:

Morning all,GFS /ECM blowing in from a west to northwest temperatures more around average into

first week of December nothing mild Gefs showing an average period coming up also.

The Azores high never to far away with some ridging into mid Atlantic keeping west/northwest flow

going.Waiting to see if Atlantic takes complete charge or a pressure rise occurs hopefully to our

northwest/northeast.

Atlantic all year has never had a proper foothold.. I guess if it is ever going to it is now when it is at it most active... but this doesn't mean it will.. my hunch and it's just a hunch with the la Nina base state heights to our west will continue to have a strong influence and we may have a week or two of a push and pull between westerlies and something more ridge like.. there is then a possibility the ridge will become more dominant again in the run up to Christmas. 

[jamesgold]

GFS 0z frequently at the very mild end of its ensembles, before it gets too gloomy in here

[Methuselah]

There could be something a wee bit wintry (sleet, freezing rain?) ahead of Monday's incoming warm front. I might even see a snowflake!

    

Edited November 25, 2021 by Ed Stone

[Anthony Burden]

11 minutes ago, damianslaw said:

Atlantic all year has never had a proper foothold.. I guess if it is ever going to it is now when it is at it most active... but this doesn't mean it will.. my hunch and it's just a hunch with the la Nina base state heights to our west will continue to have a strong influence and we may have a week or two of a push and pull between westerlies and something more ridge like.. there is then a possibility the ridge will become more dominant again in the run up to Christmas. 

Hi you must be reading my mind,la-NINA/EQBO hopefully will encourage this weather pattern to occur,time will

tell but a good chance in my book of happening.

[TSNWK]

More heights to our north.. can they topple into scandi!

[TSNWK]

On 25/11/2021 at 10:38, TSNWK said:

More heights to our north.. can they topple into scandi!

Bloomin heck! It only went and did it..

Edited November 25, 2021 by TSNWK

[Methuselah]

So, here we are at the fabled Day 10; and there must be so many 'if only's in there to 'fit' anyone's innermost desires? Even more so, if those desires involve Scottish ski slopes!

    

Edited November 25, 2021 by Ed Stone

[sheikhy]

Just now, TSNWK said:

Bloomin heck! It only went it did it..

Where the heck did that come from!i gave up at 192 hours!!how did that happen from no where lol!!

[Eskimo]

Some flabby heights in Scandinavia, but with too much energy riding over the top, it's only going to go one way. 

[joggs]

2 minutes ago, Eskimo said:

Some flabby heights in Scandinavia, but with too much energy riding over the top, it's only going to go one way. 

What way is that then. There's a couple of possibilities for me.

The lower heights to the SW could link up with the EU trough or the Azores high links up with the Scandi high for me with the lower heights to the SW fading

[TSNWK]

On 25/11/2021 at 10:47, Eskimo said:

Some flabby heights in Scandinavia, but with too much energy riding over the top, it's only going to go one way. 

You sure.. holding it's own  quiet nicely

 

[That ECM]

On 25/11/2021 at 10:47, sheikhy said:

Where the heck did that come from!i gave up at 192 hours!!how did that happen from no where lol!!

Not from nowhere imo. A few ens have hinted at this. T120 plus is JFF. Nothing changed but some are writing off December which is crazy imo.

[TSNWK]

Enjoyed that run.. hope lives on..but as they say.. it's the hope that kills you but we love it.  Ensemble members will be interesting to see where this sits

 

[weirpig]

1 hour ago, sheikhy said:

Hmmm gfs seems to have snow for eastern england for a good number of hours on the 06z for saturday!cant it push further west though?!

Models still all over the place   for whats its worth the Herm / Arome and Arp  bring the front through the spine of the country   Still very high winds on most models also 

Edited November 25, 2021 by weirpig

[MATTWOLVES 3]

2 hours ago, knocker said:

The medium term anomalies are beginning to indicate what the ext means have been indicating for a while. Which is the tpv lobe returning to it's winter residence northern Canada; a westerly upper flow, perhaps nudging a tad north of west, courtesy of the Azores HP retaining some influence; and the Euro trough retreating to eastern parts. Temps around average. I mean, what's not to like!!

 

I would imagine there are a thousand members on here who would say the opposite! WHAT IS TO LIKE!

Not a great extended outlook by any means though. In all fairness the oz output looked exactly the same 24hrs ago,before improving during the day.

I'm not convinced the vortex being placed towards the NW spells the end for a month though(like some are hinting at)

And there seems to be one hell of a lot of faith being put on that mjo cycle too get us out of trouble..Far to many variables and contrasting signals which can end up overriding one another in the current climate for my liking.

So just a watching brief from me today. Hopefully tonight's EC46 will shed some more light on the chances of Heights building around scandy next month.

Edited November 25, 2021 by MATTWOLVES

[Severe Siberian icy blast]

3 hours ago, knocker said:

The medium term anomalies are beginning to indicate what the ext means have been indicating for a while. Which is the tpv lobe returning to it's winter residence northern Canada; a westerly upper flow, perhaps nudging a tad north of west, courtesy of the Azores HP retaining some influence; and the Euro trough retreating to eastern parts. Temps around average. I mean, what's not to like!!

 

Potential for wedges directly north/ north east diverting things more nw/se? Looks primed 

Edited November 25, 2021 by Severe Siberian icy blast

[Man With Beard]

Wind update for tomorrow night. Lots of short range models now in view of the event. There's a bit of a split. One group generally sees peak gusts to 80mph or 90mph on NE coasts, 70-80 mph for coasts the west - ARPEGE showing 100mph but it frequently overdoes things. The EURO4 chart is reasonably representative of this cluster (note: these are maximum wind speeds during the run, not one particular time slot)

 

However, another group is now keeping the worst winds off the east coast, and not so significant for the west. The GFS has followed this group today - still 60-70mph for the NE but nothing like as bad as the others:

 

Edited November 25, 2021 by Man With Beard

[PiscesStar]

Still looking OK for medium term... More runs needed. Certainly feeling bitingly Cold atm guys  

[That ECM]

On 25/11/2021 at 11:26, Severe Siberian icy blast said:

Potential for wedges directly north/ north east diverting things more nw/se? Looks primed 

A few more than the earlier run.

[Tim M]

12 minutes ago, Man With Beard said:

Wind update for tomorrow night. Lots of short range models now in view of the event. There's a bit of a split. One group generally sees peak gusts to 80mph or 90mph on NE coasts, 70-80 mph for coasts the west - ARPEGE showing 100mph but it frequently overdoes things. The EURO4 chart is reasonably representative of this cluster (note: these are maximum wind speeds during the run, not one particular time slot)

 

However, another group is now keeping the worst winds off the east coast, and not so significant for the west. The GFS has followed this group today - still 60-70mph for the NE but nothing like as bad as the others:

 

MWB... thanks for this, as a complete novice which group is/are the graphics relating to? - Thank you have seen edit of your graphics, much appreciated!

Edited November 25, 2021 by Tim M