model discussion Model output discussion - closing in on Winter

[TSNWK]

On 25/11/2021 at 11:32, That ECM said:

A few more than the earlier run.

 

Good news ? The 06z was not without support in late reliable and early guesswork with the scandi high

[carinthian]

18 hours ago, carinthian said:

Yes , I know its another run from GFS. This time the jet out to 300hrs not showing a flat mode. So I am wondering whether the model is now picking up some resistance with a cold block and build of pressure to the Northeast ?  Would be nice if cold would win out for a change . Think I am still in the edging towards cold outcome camp !

C

Just a follow up from yesterdays post above. I think the models are currently having a problem in forecasting the longer term jet patterns across the NH.  As some others on here have mentioned, the normal Atlantic zonal or flatten pattern has been weak for much of this year with a amplified mode dominant for much of the time. Many of the low pressure systems formed close or to the NW of the British Isles and had the characteristics of a slower holding pattern as they moved in a southward meridian course . Now of course the jet profiles should at this time of year speed up and change to its usual less amplified mode, but will it. ? I am not wholly convinced. Maybe , we are heading towards a Scandinavian Winter High of the type we have not seen for many years !

C

[tight isobar]

The ens throughout the latest suite @6z offering no real solutions.. lots of scatter! We’ll leave this to the rawest outs @ rolling operationals for the nxt few days!- that would be a sensicle option imo. I’ll personally be delving through the Nina latest reference for “perhaps some disclosure “?!.. @ being kept toe-tipped firmly.

Edited November 25, 2021 by tight isobar

[tight isobar]

On 25/11/2021 at 11:45, carinthian said:

Just a follow up from yesterdays post above. I think the models are currently having a problem in forecasting the longer term jet patterns across the NH.  As some others on here have mentioned, the normal Atlantic zonal or flatten pattern has been weak for much of this year with a amplified mode dominant for much of the time. Many of the low pressure systems formed close or to the NW of the British Isles and had the characteristics of a slower holding pattern as they moved in a southward meridian course . Now of course the jet profiles should at this time of year speed up and change to its usual less amplified mode, but will it. ? I am not wholly convinced. Maybe , we are heading towards a Scandinavian Winter High of the type we have not seen for many years !

C

My money is rapidly heading that way @momentumn overide= Scandinavia formats.

[throwoff]

It still looks like vast parts of the country could at least see falling snow over the weekend.

As always with these set ups it will be regional, some people will get very lucky and others might only see a couple of flakes in the wind.

Took till Jan to see a flake for me last winter so I will be loving life if we can kick off in November this year.

[Methuselah]

1 hour ago, PiscesStar said:

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

I reckon there's plenty to feel optimistic about; if, as the GFS 06Z suggests (and I realise it's a longshot), the TPV migrates back eastwards, another surge of Arctic air, into mainland Europe, would surely follow? If only!

Edited November 25, 2021 by Ed Stone

[Tim Bland]

High res models are the ones to watch for snow chances over the next few days. UKV and Euro4 showing the fist flakes of the season for many starting tomorrow with the chance of dusting on low ground even in the south by Sat morning. Ski resorts in Scotland should be rubbing their hands together . 

[Dennis]

Today a lot of snow in my area - so the white stuff came down

 

For East UK is it possible into the weekend 

 

 

[sheikhy]

Euro4 charts posted on midlands thread look a beauty for snow!!!!!latest ecm 06z judging by the pressure charts looks to be ever so slightly further east abd less deep than gfs!does that mean the snow is further east as well?!!hard to tell by just looking at the pressure charts!!

[Dennis]

very interesting into night hours 

Edited November 25, 2021 by Dennis

[BLAST FROM THE PAST]

1 hour ago, tight isobar said:

My money is rapidly heading that way @momentumn overide= Scandinavia formats.

Not so sure but not downbeat.  I think we have a pattern that is imo a big chance of dictating winter.  With shots coming like this one, vastly improved ice extent…for me will increase potency of cold shots but this La Nina signature might be hard to shift.  So plenty of ups and downs to come.  All I know is I’ve been doing early starts and it’s been a fair bit colder than I expected.  Yesterday was impressive 1c at 0430 with cloud cover and no deep cold…..

 

BFTP

[bluearmy]

Whether the gfs ens are representative of previous runs, there are a few which are standard mobile zonal but more which either repeatedly drop troughs as the flow disrupts against ridges or build a solid looking ridge across nw Europe 

to assume that we will end up in a sustained mobile zonal westerly flow of simple ridge/trough because the mean shows that could be incorrect. 

[Mike Poole]

Just a few of the high res models out to T48 (6z), HARMONIE, ICON EU and EURO4, cumulative snow fall:

EURO4 a little more bullish than the others particularly farther East.  But I think the main talking point will be the wind. 

EURO4 showing quite a battering for the NE, SE sheltered by comparison, max wind gusts up to T48:

[Ali1977]

5 minutes ago, Mike Poole said:

Just a few of the high res models out to T48 (6z), HARMONIE, ICON EU and EURO4, cumulative snow fall:

EURO4 a little more bullish than the others particularly farther East.  But I think the main talking point will be the wind. 

EURO4 showing quite a battering for the NE, SE sheltered by comparison, max wind gusts up to T48:

Add a few more hours to T54 and the amounts go up a fair bit down south

[Methuselah]

At least we can always rely on the GEFS temperature ensembles whenever clarity is required?

    

[damianslaw]

GFS 6z offers another option. Loves suggesting different ones..  heights build in behind low pressure around 3rd Dec and ridgd north and then north east into scandi maintaining the amplified flow  these sink and another NW flow takes over with mid Atlantic heights building north again.. far from a zonal westerly onslaught from the model that tends to default to this scenario. Just another plausible option. 

[throwoff]

12 minutes ago, Ali1977 said:

Add a few more hours to T54 and the amounts go up a fair bit down south

If you ever needed proof the Medway snow shield is a real thing

[Man With Beard]

A cautionary note on EURO4 snow predictions - a few years ago it was really good but something has gone wrong with it recently - last year it over predicted snow to an outrageous extent. It's even more worthy of being binned that the ECM snow depth charts.

[DJ Fart]

16 minutes ago, throwoff said:

If you ever needed proof the Medway snow shield is a real thing

Meh.  I'll join you from the Essex/Suffolk border...

[sheikhy]

Has the gfs just pushed that mini low further west at 36 hours!!!

[MattStoke]

On 25/11/2021 at 15:51, sheikhy said:

Has the gfs just pushed that mini low further west at 36 hours!!!

It has quite a bit more snow for the Midlands on this run.

[sheikhy]

Just now, MattStoke said:

It has quite a bit more snow for the Midlands on this run.

Maybe euro4 wasnt as crazy as we thought!!!

[bluearmy]

3 minutes ago, sheikhy said:

Has the gfs just pushed that mini low further west at 36 hours!!!

Correct

 more notable snowfall in that W Mids - hants line again 

Higher dp’s into e england 

 

 

[Ali1977]

Much better

[northwestsnow]

3 minutes ago, bluearmy said:

Correct

 more notable snowfall in that W Mids - hants line again 

Higher dp’s into e england 

 

 

One man's gain is another man's pain..