Model Output Discussion - Stormy Period Inbound...

[stratty]

Ah, righty-Ho. I can share only a past (now 24hr old) E4 prognosis, as not allowed to do so with current one (watch BBC for latest version). But you get the distributional idea we are running with (this prognosis to 00z Weds). I've cut the scale off, because we aren't running with the raw output on amounts and wouldn't want it taken literally. Ditto distribution nuances, not least as this isn't the current output!

......but light blue = 6 inches Fergie?

[shaky]

Ah, righty-Ho. I can share only a past (now 24hr old) E4 prognosis, as not allowed to do so with current one (watch BBC for latest version). But you get the distributional idea we are running with (this prognosis to 00z Weds). I've cut the scale off, because we aren't running with the raw output on amounts and wouldn't want it taken literally. Ditto distribution nuances, not least as this isn't the current output!

thanks for that fergie! ! Hopefully it upgrades in the next update and a wider area has accumulative snowfall! !

[pdiddy]

Pleasant by day,cold at night almost Springlike anticyclonic February your favoured option fergie?

Think it will depend on the flow: if the high is centred to the South, then perhaps, if it's a little further West, we could be in the colder flow, one presumes.

[chicken soup]

Ah, righty-Ho. I can share only a past (now 24hr old) E4 prognosis, as not allowed to do so with current one (watch BBC for latest version). But you get the distributional idea we are running with (this prognosis to 00z Weds). I've cut the scale off, .....because we aren't running with the raw output on amounts and wouldn't want it taken literally. Ditto distribution nuances, not least as this isn't the current output!

I take it the blue bits are rain?.

[blizzard81]

I take it the blue bits are rain?.

No, just less intense snowfall.

[fergieweather]

I take it the blue bits are rain?.

No. This is only snow prognosis. Blue just trace amounts or effectively nil.

[summer blizzard]

Think it will depend on the flow: if the high is centred to the South, then perhaps, if it's a little further West, we could be in the colder flow, one presumes.

Were still in the time of year when 1020mb+ will likely be enough to deliver an inversion unless we get a stellar flow like 98.

Still, I don't mind dry and sunny.

[Mucka]

Good to see some growing broad agreement now by late Jan between EC products, UKMO-GLOSEA and now NCEP modelling for prospects of a more settled, anticyclonic flavour to finish the month and possibly on into early Feb. Flow direction hard to call eventually (perhaps transition into fog/freezing fog/frost territory before a shift to anticyclonic W/SW'ly as per EC Monthly?). Either way, growing consensus on losing the deep cyclonicity... eventually!

 

 

Can't wait for the long fetch Southwesterly into Feb.

[NorthYorksWeather]

12z NMM showing a trough moving eastwards over Northern/Central areas during Tuesday afternoon, looks like some places will see some snow however most likely will be confined to higher ground depending on intensity (hope I'm wrong).

We then see a few disturbances as we head into Wednesday further South, these charts correlate well with Ian F's exclusive snow map.

 

Doesnt appear to be any countrywide snow events on the horizon, however some people could see there first snow of the winter.

Edited January 11, 2015 by vizzy2004

[Cloud 10]

There seems to be no escaping the mid-week storm now,with the ECM having it a touch further south than yesterday.

 

[AWD]

The Euro4 model now encroaching upon Tuesdays forecast unusually cold polar maritime airflow.

Some cold upper air temperatures being swept down from the NW;

Along with low thickness values;

And although I can't find a chart to support my view, I suspect we will see ever lowering WBFL values too.

Leading to some snowfall for a wide area of northern and western parts of the UK, initially over hills but some wintriness also likely Tuesday night with the aid of nocturnal cooling to lower levels too.

Not the holy grail a lot of snow fanatics want, but it's better than nothing;

[Paul]

The trough Tuesday pm coming into range on the Netwx-SR now - looks like it could get pretty interesting into parts of the SW and the midlands as it heads inland!

 

 

The storm weds/thurs is still catching the eye though....

 

[SMU]

ECM 120

http://www.meteociel.fr/modeles/ecmwf/runs/2015011112/ECU1-120.GIF?11-0

 

some possible snow for the home counties- Particularly north of London

 

S

[knocker]

The ECM sequence for the storm Weds.  Winds 900mbs

 

18z Weds Low 956mb NW of Ireland with SW winds Irish Sea and west Wales and Cornwall 70+ kts.

 

00z Thurs Low just off Northern Ireland 957mb strong wind band now SE quarter of England into North Sea 65+kts

 

06z Low Thurso with strong westerlies over the UK and front with very strong winds approaching Denmark.

[Eugene]

Can't wait for the long fetch Southwesterly into Feb.

 

 

He never said that, that would bring dull windy weather anyway with little variation between day and night, how tedious. 

[SMU]

ECM is as per I posted earlier-

 

Very cold air in situ mixed all the way down to the surface over the UK with some sort of trough disruption to the west

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011112/ECH1-168.GIF?11-0

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011112/ECU0-168.GIF?11-0

 

-7c air in the SE will for probably be cold with a gentle NW wind. Very frosty as well.

S

[Frosty.]

A few comments earlier rubbished those gfs snow charts i posted but it's interesting to note the updated met office 3-5 day has mentioned snow to low ground on Tuesday. And where the trough lines occur there could be a surprising amount of snow in a short space of time. Things are really cranking up now, we have a wintry Tuesday, a stormy midweek and then another cold blast later in the week..this is more than I could have hoped for considering how poor the models were looking a week ago.

Edited January 11, 2015 by Frosty.

[nick sussex]

I'm liking the look of the ECM T168hrs, can we in future runs get a bit stronger pressure rise to the ne.

 

An improvement in terms of potential compared to the 00hrs but theres still these model differences upstream from an earlier timeframe.

 

A mix of rain and snow pushing east at T192hrs, the slack flow helps here as there could be some embedded cold at the surface, snow likely inland away from windward coasts.

 

Of course at this range a lot can change but certainly a better run from the ECM so far in terms of cold prospects.

Edited January 11, 2015 by nick sussex

[stratty]

A few comments earlier rubbished those gfs snow charts i posted but it's interesting to note the updated met office 3-5 day has mentioned snow to low ground on Tuesday. And where the trough lines occur there could be a surprising amount of snow in a short space of time. Things are really cranking up now, we have a wintry Tuesday, a stormy midweek and then another cold blast later in the week..this is more than I could have hoped for considering how poor the models were looking a week ago.

...........I think the charts have looked interesting for this coming week since New Year Frosty. GFS has certainly been keen on this storm midweek since it came into T300s, but was showing more of a ridge of HP for the end of the week.

[shaky]

Boy the ecm.looks like a slider snowfest across england! ! 850s look good aswell!!

[marksiwnc]

Ah, righty-Ho. I can share only a past (now 24hr old) E4 prognosis, as not allowed to do so with current one (watch BBC for latest version). But you get the distributional idea we are running with (this prognosis to 00z Weds). I've cut the scale off, because we aren't running with the raw output on amounts and wouldn't want it taken literally. Ditto distribution nuances, not least as this isn't the current output!

I can imagine the mountains of snowdonia would get quite a bit of snow from the setup.???

[I remember Atlantic 252]

Boy the ecm.looks like a slider snowfest across england! ! 850s look good aswell!!

 

not enough heights to the north for that, generally a flat pattern, wouldn't rule some wet snow out for our locations mind you

[fergieweather]

The Euro4 model now encroaching upon Tuesdays forecast unusually cold polar maritime airflow.

Some cold upper air temperatures being swept down from the NW;

image.jpg

Along with low thickness values;

image.jpg

And although I can't find a chart to support my view, I suspect we will see ever lowering WBFL values too.

Leading to some snowfall for a wide area of northern and western parts of the UK, initially over hills but some wintriness also likely Tuesday night with the aid of nocturnal cooling to lower levels too.

Not the holy grail a lot of snow fanatics want, but it's better than nothing;

image.jpg

Yes, that chart only to 12z Tues (E4 goes much further but I don't know how far run extends on public access). Later Tues is when the colder air spreads south. So the 12z Tues frame not wholly representative of the key sequence. I hope to offer an update later.

[NoTraction]

Azores high furthest west i have seen for a really really long time on ecm 240hrs

 

 

 

 

 

could that low aproaching the uk disrupt further to the south!!!!!

[AWD]

Yes, that chart only to 12z Tues (E4 goes much further but I don't know how far run extends on public access). Later Tues is when the colder air spreads south. So the 12z Tues frame not wholly representative of the key sequence. I hope to offer an update later.

Yes, very much so. From my understanding and sources, EURO4 only goes to T48 in public domain though, hence why I couldn't use it any further.

Tuesday night looks like the peak of any wintry activity, especially for West Country, SW Moors, South Midlands etc where a small covering of snow can't be ruled out by dawn Wednesday.