Model Output Discussion - Into 2024

[Aiden2012]

Just now, NewEra21 said:

Hopefully the GFS is very wrong, but I do feel it’s latched onto things before ECM this winter, always feel like ECM is a step or two behind and always playing catchup.

Yeah my feeling aswell, if that happens taking a long break from model watching it is soooo draining

[tight isobar]

2 minutes ago, Andy Bown said:

Which cold are people looking for to reach the UK!? 
 

It’s cold now! 
 

Always hunting for narnia! 

Im personally looking 4 the new ice age

[bradymk]

No real change. The GFS 6z not quite getting the initial cold far enough south in the med range for the whole of the UK, but I wouldn't worry too much about that for now. The southward extent of that is going to be almost impossible for the models to nail down at this stage and it is clearly chopping and changing run by run. Plus we fortunately have the UKMO and ECM showing it further south for now.

Even on this GFS run, the cold front doesn't move back further north than the Midlands from late Sunday until late Thursday. If you look at the 2m temps too, it is still a very cold week for many, particularly Midlands and further north.

I also think it is encouraging that the GFS 6z is then still trying to disrupt lows passed this point, at day 9/10. Anyway, probably silly over analysing it for now, next runs...

 

[Sky Full]

20 minutes ago, Ali1977 said:

At day 7 the UKMO and ECM have this -

………
 

Oh what a beauty!   Pity it’s still in FI but we can dream, can’t we?

[Martz86]

It would be nice to have a model group just for those that know what their talking about, reading through this one is very confusing, shame really as I quite like reading the knowledgeable posts but it's becoming tedious filtering through it all. 

[BLAST FROM THE PAST]

They all look similar at t144 and all then allow the Atlantic attack from SW after.  It seems to me how the attack will manifest itself.  Is t168 when the westerly inertia is set to kick back in?

 

BFTP

[jonboy]

I rarely comment in this thread as I'm not a great reader of the models.

However there are some fantastic charts being shown which hopefully will bring winter joy to many. But lets put into perspective each model.

Firstly the GFS (Global Forecasting System) this is an American based forecasting tool it will be great at getting it right around America it will be less right further afield ie europe especially the further out the model prediction goes.

Gem is a Canadian model so much the same applies

ECM a European model great for us but less likely to get what happens around the US right again the further out the modelling goes. ICON is german I believe so similar to ECM and of course UKMET model will be great for us but again maybe poor at modelling whats happens in the states.

My point is don't take any model as gospel especially beyond 5 days try and assess each model taking account of their individual bias nearer to their own locations. We are going to get a proper winter spell and winter is just beginning.

[joggs]

Would the GFS not have the better handling of things over North America later in in the run?. 

If the euros trend this way this evening,it could be telling.

[Paul33]

3 minutes ago, Martz86 said:

It would be nice to have a model group just for those that know what their talking about, reading through this one is very confusing, shame really as I quite like reading the knowledgeable posts but it's becoming tedious filtering through it all. 

Blank pages will never sell !!!

[northwestsnow]

Sunday onwards looks very very complex for our little island ...

Nightmare for forecasters because the snow /rain boundary could move a lot at short notice ...

[chris55]

3 hours ago, Tim Bland said:

Wow ECM…..

One day…….one of these ECM snow charts will actually come off.

Ive seen a good few modelled over the years with this classic “blizzard” scenario,  where an active low slides in against a cold block, but they never seem to come to fruition. Maybe this year is the year for one to verify  

Being in the Cotswolds this is pretty much the best way we can achieve deep snowfall.

[Mcconnor8]

1 minute ago, jonboy said:

I rarely comment in this thread as I'm not a great reader of the models.

However there are some fantastic charts being shown which hopefully will bring winter joy to many. But lets put into perspective each model.

Firstly the GFS (Global Forecasting System) this is an American based forecasting tool it will be great at getting it right around America it will be less right further afield ie europe especially the further out the model prediction goes.

Gem is a Canadian model so much the same applies

ECM a European model great for us but less likely to get what happens around the US right again the further out the modelling goes. ICON is german I believe so similar to ECM and of course UKMET model will be great for us but again maybe poor at modelling whats happens in the states.

My point is don't take any model as gospel especially beyond 5 days try and assess each model taking account of their individual bias nearer to their own locations. We are going to get a proper winter spell and winter is just beginning.

Pretty sure it doesn't work in this way, the ECM in the past was always very good at modelling the Hurricanes in the US compared to GFS, and often GFS is actually quite good around Greenland, both models get similar data inputs it is more down to their physics understanding as to how they model things differently.

[Midlands Ice Age]

9 minutes ago, NewEra21 said:

Hopefully the GFS is very wrong, but I do feel it’s latched onto things before ECM this winter, always feel like ECM is a step or two behind and always playing catchup.

I disagree here  New..

As per my post above ECMWF had exactly the same wobble last weekend (and  days earlier)

The real interest is what is causing the 2 models to behave in this way.

MIA

[Downburst]

2 minutes ago, Sky Full said:

Oh what a beauty!   Pity it’s still in FI but we can dream, can’t we?

It's a pretty reasonable possibility with this undercut low, it's certainly happened before and looks a good one to watch.

[Neve]

Be nice my first post here and I'm just a proper rookie and very basic knowledge on chart reading but been keeping an daily eye on MOGREPS and today isn't looking as tidy as previous runs. Same applies to other areas

Edited January 9 by Neve

[MattStoke]

8 minutes ago, Sky Full said:

Oh what a beauty!   Pity it’s still in FI but we can dream, can’t we?

GFS similar but a little further north so naturally the consensus in here is that it's terrible.

[Gowon]

7 minutes ago, Martz86 said:

It would be nice to have a model group just for those that know what their talking about, reading through this one is very confusing, shame really as I quite like reading the knowledgeable posts but it's becoming tedious filtering through it all. 

There is a thread but it can get boring in there.

4 minutes ago, Paul33 said:

Blank pages will never sell !!!

Snap!

[bluearmy]

The gfs suite continues to react to the split Canadian segment recoupling to the main tpv our side of the meridian post day 9. In addition we also see the nwp still wanting to send the Asian segment to Canada in the 10/15 day period 

add in an Arctic ridge and you have a recipe for the entrance of our mate Shannon 

we know that movement of the vortex back and forth fires up the Atlantic - if that is what happens then we need to hope that we retain a sufficient n Atlantic ridge or wedge to deflect the jet far enough south thus we stay in the cold air. Tough to imagine that euro heights will stay low enough to keep that pattern in place 

[Paul_1978]

 

1 hour ago, sheikhy said:

Gfs o6z terrible!!!!!

 

1 hour ago, feb1991blizzard said:

Yes, its all going wrong now - very wrong.

Am I in some kind of parallel universe here? I think most of us want snow, not something cold and dry. Lots of runs are showing snow for next week (exact placement to be determined). We know that there is likely to be a relaxation of cold after this before the next cold chase into Feb. Am I missing something here? If you are wanting snow I don't see there is a lot to complain about - it's quite exciting in my view.

[Met4Cast]

15 hours ago, Met4Cast said:

In terms of where the polar boundary lies that is something that's going to shift north & south probably 100 times before we actually get to the period of interest, I wouldn't place too much focus on that. 

Returning momentum in the form of the jet stream edging back northwards seems a certain bet, it will happen at some point as the MJO continues it's progression eastwards and on the back of the recent (but brief) AAM tendency dip. How this looks synoptically will depend on how much blocking we retain to the north. It could be that the jet doesn't quite get into the UK and instead we remain cold for far longer (the 00z and 06z GFS det runs played with this scenario) or it could be, like the GEM we see a widespread, high impact snow event (perhaps multiple) as lows push up into the cold air across the UK. 

Current thinking is the 20th-25th for a potential Atlantic return (of sorts) and therefore increasing risk of high impact weather. Where? How? Who knows, that wont be resolved for a longgggg time.

In any case, we've already seen a return to +AAM tendency and frictional torque will soon return to +ve followed by another likely +EAMT event driving AAM tendency upwards, total GLAAM & GWO remain coupled with the El Nino base state. MJO progression likely through the Maritimes and back into phases 6 >7 around the end of January/beginning of February (MJO timing always difficult).

In essence, any waning of the block and Atlantic return will likely be temporary with renewed blocking likely into early February, perhaps Greenland/Scandinavia, more likely is we wont see the block to the north become completely eroded, cold air will never be far away. 

Very, very positive moving forward away from the chopping and changing of NWP outputs and attempting to nail down precise details 10+ days away.

FWITW the 00z ECM is highlighting where I broadly expect things to head as outlined in the quoted post from yesterday.

Cold air across the UK vs incoming disruptive lows = high impact snowfall events. 

I do think the ECM is being a little too progressive with the lows though, I suspect the first couple will "miss" and pass to the south, again still looking towards the 20th - 20th as a timeframe, although a day or two before can't be discounted given current modelling. 

The GFS is absolutely horrible when it comes to handling split flows in the Atlantic & disrupting low pressure systems, it depends to blow them up and barrel them through before correcting ever south closer to the time so I'd not worry too much about what the GFS or GEFS is showing for that matter. UKMO, ECM and to some extent GEM will give better guidance going forward.

All in all - No changes to the outlook. 

[MATTWOLVES 3]

25 minutes ago, MidnightSnow said:

If the ECM / UKMO / Met Office were all looking poor, but the GFS was showing nirvana, many on here would happily dismiss the GFS. So why wont you do the same when it's the other way around?

I'm amazed tbh..over the years how many times have we heard that an ecm ukmo blend beats everything hands down! The gfs picks up the signal gets nervous with it..hands over the batten to ecm who brings the cold back,hands it back to gfs who drops it again before handing it over to the ukmo who runs for the finishing  line in nearly record breaking time! But rrrr...it would have been a new world record if only gfs wouldn't have kept dropping the batten! A little NWP Olympics terminology there folks.

The 0z mogreps do persist with a good chunk of colder members!

Am I worried over gfs! Never...it will fall back into line and it will yet again fall back out of line..thats its nature...it always wants to play different to the other models like a spoilt child.

Edited January 9 by MATTWOLVES 3

[Paul_1978]

15 minutes ago, Martz86 said:

It would be nice to have a model group just for those that know what their talking about, reading through this one is very confusing, shame really as I quite like reading the knowledgeable posts but it's becoming tedious filtering through it all. 

Not if you mute the right people, and it makes for much more pleasant viewing.

[Buzz]

12 minutes ago, Martz86 said:

It would be nice to have a model group just for those that know what their talking about, reading through this one is very confusing, shame really as I quite like reading the knowledgeable posts but it's becoming tedious filtering through it all. 

Do as I have done - add all of the problematic posters to your ignore list. It'll take a while but it's well worth it - I now mainly only see those posts which are actually useful. Reading this thread is now a pleasure, not a chore.

In addition to that there is of course the very useful Highlights thread, but that does rely on others actually marking posts from here as Insightful and not abusing the feature.

[Gowon]

6 minutes ago, Paul_1978 said:

 

 

Am I in some kind of parallel universe here? I think most of us want snow, not something cold and dry. Lots of runs are showing snow for next week (exact placement to be determined). We know that there is likely to be a relaxation of cold after this before the next cold chase into Feb. Am I missing something here? If you are wanting snow I don't see there is a lot to complain about - it's quite exciting in my view.

Yes, if you are in the north.  You guys have a better chance at this big snow event whilst we end up with mainly cold rain.

Edited January 9 by Gowon

[Chrisover93]

2 minutes ago, Met4Cast said:

FWITW the 00z ECM is highlighting where I broadly expect things to head as outlined in the quoted post from yesterday.

Cold air across the UK vs incoming disruptive lows = high impact snowfall events. 

I do think the ECM is being a little too progressive with the lows though, I suspect the first couple will "miss" and pass to the south, again still looking towards the 20th - 20th as a timeframe, although a day or two before can't be discounted given current modelling. 

The GFS is absolutely horrible when it comes to handling split flows in the Atlantic & disrupting low pressure systems, it depends to blow them up and barrel them through before correcting ever south closer to the time so I'd not worry too much about what the GFS or GEFS is showing for that matter. UKMO, ECM and to some extent GEM will give better guidance going forward.

All in all - No changes to the outlook. 

What are your thoughts in terms southern coastal counties in terms of lows bumping into cold air will it all fall as rain 

 

and I agree GFS is actually ending it before it gets going with progressive lows