Model output discussion - Closing in on Christmas

[That ECM]

Just now, Scott Ingham said:

Its not necessarily just to high ground with the thicknesses and slack cold dense air. I think were in danger of underestimating snowfall potential 

I do hope so

[Matt H]

23 minutes ago, SLEETY said:

yeah like a gfs chart in fl ever verifies,even before then the run looks suspect,too much concern about gfs charts over t+192 hours again

Has the GFS cheated on you in the past or something? 

[MATTWOLVES 3]

18 minutes ago, SLEETY said:

yeah like a gfs chart in fl ever verifies,even before then the run looks suspect,too much concern about gfs charts over t+192 hours again

Sleety this makes know sense...being as this is a model discussion thread,people will discuss the models,whether it be at day 1 or day 14,and being as GFS run out to this range,us mere mortals will want to ponder over it...Its not about these models being able to nail down exact conditions,because at this range,that's nigh on impossible. Its really all about spotting potential trends,and sometimes when many ensembles flag these scenarios up,they can be on to Something! If its all pointless we may as well all email those guys at Exeter and tell them to stop writing up the monthly update...on the basis that its unlikely to happen.

Closer to home I feel plenty of ensembles point towards possible snow events with the positioning of some of them Lows...one to watch perhaps.

[Scott Ingham]

1 minute ago, That ECM said:

I do hope so

Me and you both hahaha for what its worth i think things will be 1000 miles further east and south anyway

[SMU]

One last indulgence > Significant upgrade in the ENS for Xmas day 

I checked the panels > London 138 coldest member is -9.2c !!! Will snow flurries! 

( ENS 23 )

[Jason M]

6 minutes ago, Scott Ingham said:

Its not necessarily just to high ground with the thicknesses and slack cold dense air. I think were in danger of underestimating snowfall potential 

Agree that you can't rule out low ground snow. I suspect the SE & EA will be very unlikely to see any from this set up as we will always be on the mild side of things. Down here we will get a good soaking but nothing else, but Midlands northwards will at least be in the game.  If I lived in Buxton I'd be getting the snow boots out of storage though. For clarity to others I'm referring to what occurs post Xmas.

As per what happens maybe 30% chance of very cold easterly. Still odds against but higher odds than normal climatic position if that makes sense (or not!).

Edited December 19, 2020 by Jason M

[Laurence Hill]

1 minute ago, Steve Murr said:

One last indulgence > Significant upgrade in the ENS for Xmas day 

I checked the panels > London 138 coldest member is -9.2c !!! Will snow flurries! 

( ENS 23 )

Indulge as much as you want Steve.

[northwestsnow]

10 minutes ago, feb1991blizzard said:

The GEFS are a relative stonker, will the eps follow suite after a few downgrades recently?

The 12Z GEFS are cold for Christmas Eve ..I would saythe op is at the very top end regarding the northward extent of the low...

 

Edited December 19, 2020 by northwestsnow

[northwestsnow]

3 minutes ago, Steve Murr said:

One last indulgence > Significant upgrade in the ENS for Xmas day 

I checked the panels > London 138 coldest member is -9.2c !!! Will snow flurries! 

( ENS 23 )

Just keep the posts coming when time allows Steve.

Esp if we see a cold spell incoming!

[Scott Ingham]

1 minute ago, Steve Murr said:

One last indulgence > Significant upgrade in the ENS for Xmas day 

I checked the panels > London 138 coldest member is -9.2c !!! Will snow flurries! 

( ENS 23 )

Still time for troughs etc to form as well. I have had 50 quid on Airport at 3-1. Interstingly Leeds Bradford is shorter at 2-1

[Mucka]

GFS ensembles firming up now. This is a  pretty solid mean at 192

 

 

EDIT

Now I see it was already posted by @Sweatyman

But worth seeing again

Edited December 19, 2020 by Mucka

[northwestsnow]

I know some have an opinion GFS is superior in this situation.

I'm sorry, I can't agree.

EC/UKMO are superior forecasting computers.

So, I expect EC to look flatter in the Atlantic sector  at 144 , probably similar to UKMO..( which I'm still not keen on).

[Scott Ingham]

7 minutes ago, Jason M said:

Agree that you can't rule out low ground snow. I suspect the SE & EA will be very unlikely to see any from this set up as we will always be on the mild side of things. Down here we will get a good soaking but nothing else, but Midlands northwards will at least be in the game.  If I lived in Buxton I'd be getting the snow boots out of storage though. For clarity to others I'm referring to what occurs post Xmas.

As per what happens maybe 30% chance of very cold easterly. Still odds against but higher odds than normal climatic position if that makes sense (or not!).

Yeah im following the -4 upper line downwards and that would agree with your assumption. Anything not in the light blue 850s for me have a chance of low ground snow on face value given how slack it looks and the thickness charts. Its all way too far out though. We are of course better off nailing this -8 values to save any suicides on the forum hahaha 

[Scott Ingham]

1 minute ago, northwestsnow said:

I know some have an opinion GFS is superior in this situation.

I'm sorry, I can't agree.

EC/UKMO are superior forecasting computers.

So, I expect EC to look flatter in the Atlantic sector  at 144 , probably similar to UKMO..( which I'm still not keen on).

As a whole they are but years of model watching have shown GFS to be the master with North Atlantic ridge scenarios

[sheikhy]

3 minutes ago, northwestsnow said:

I know some have an opinion GFS is superior in this situation.

I'm sorry, I can't agree.

EC/UKMO are superior forecasting computers.

So, I expect EC to look flatter in the Atlantic sector  at 144 , probably similar to UKMO..( which I'm still not keen on).

Gota agree with u mate!!been following the models for over 20 years now and i gota say ecm and ukmo always!!but can gfs claw it back in this saga?

[Mike Poole]

1 minute ago, northwestsnow said:

I know some have an opinion GFS is superior in this situation.

I'm sorry, I can't agree.

EC/UKMO are superior forecasting computers.

So, I expect EC to look flatter in the Atlantic sector  at 144 , probably similar to UKMO..( which I'm still not keen on).

I think it is down to what these organisations build into their models, UKMO is best for anything local to the UK.  But the developments that might set this up are over the US - and the GFS purpose is to forecast for the US, so I can entirely see why it could be onto something here.  Contrast an easterly, or slider scenario, where it has proven time and time again to be rubbish.

[northwestsnow]

1 minute ago, Scott Ingham said:

As a whole they are but years of model watching have shown GFS to be the master with North Atlantic ridge scenarios

We will see i guess.

Intriguing stuff for sure...

[Scott Ingham]

Just now, sheikhy said:

Gota agree with u mate!!been following the models for over 20 years now and i gota say ecm and ukmo always!!but can gfs claw it back in this saga?

I guess well see but i strongly believe models have specialist synoptics and this is the GFS specialist area. The ECM is better with scandi blocking

[Jason M]

Just now, Scott Ingham said:

As a whole they are but years of model watching have shown GFS to be the master with North Atlantic ridge scenarios

Yes. Those who rubbish GFS are talking rubbish IMHO (albeit it doesn't get rubbished when its showing blizzards). GFS has its weaknesses but its a good model and for our purposes the GEFS allow us to better contextualize the output. METO is king for days 1-5 but its day 6 output is often miles out.

[Allseasons-Si]

Is the mean on the funny juice here...

still smacks of potential even at 312

Meteociel - Panel GEFS

WWW.METEOCIEL.FR

 

[Cold Winter]

1 minute ago, sheikhy said:

Gota agree with u mate!!been following the models for over 20 years now and i gota say ecm and ukmo always!!but can gfs claw it back in this saga?

I would always favour ECM/UKMO over GFS but that doesn’t mean the former are always right. The consistency from the GFS recently has been of note.

[feb1991blizzard]

1 minute ago, Mike Poole said:

I think it is down to what these organisations build into their models, UKMO is best for anything local to the UK.  But the developments that might set this up are over the US - and the GFS purpose is to forecast for the US, so I can entirely see why it could be onto something here.  Contrast an easterly, or slider scenario, where it has proven time and time again to be rubbish.

Remember though, US forecasters prefer the Euros generally, you can see that when they poke fun at their own model in state forecasters minutes.

[Alexis]

Decent GFS. Until it gets stuck in washing machine mode.

[Scott Ingham]

1 minute ago, Jason M said:

Yes. Those who rubbish GFS are talking rubbish IMHO (albeit it doesn't get rubbished when its showing blizzards). GFS has its weaknesses but its a good model and for our purposes the GEFS allow us to better contextualize the output. METO is king for days 1-5 but its day 6 output is often miles out.

Yeah taking into account model bias is one of the skills needed to make a forecast and discount runs that dont look right. The ecm i think is under amplifying in this case 

[Djdazzle]

You can argue about which model is best until the cows come home!

Any prolonged cold is still an outside bet, even with the improvements in the GEFS.