Model Output Discussion - Into 2024

[Cymro]

14 minutes ago, offerman said:

this is so true, even the weather people local presenters would often say M4 corridor, and quite often it would be snow to the north of this and rain in the south quite often

I think this is perhaps very much an England thing re north of the M4 and it doesn't feature much in Welsh weather as in general Wales as a whole is farther north than the M4 to the east of Bristol.

With that being said it does strike me that the pointy bit of SW England a peninsula if you will and likewise Kent to the east have an onshore sea breeze from multiple directions unlike central southern England above the M4 and Wales (excluding the Gower peninsula and Pembrokeshire. 

That could have a huge impact in mixing out colder surface conditions quicker hence lows make greater progress inland before coming to a halt. 

 

 

Edited January 9 by Cymro

[Scott Ingham]

8 minutes ago, tight isobar said:

Blank em bud.

How do I block on here? I’m trying now

[Woldsedge]

7 minutes ago, Garthvader said:

Is there any science behind the cold being embedded harder to shift or is this a bit of a myth? ....serious question btw!

No particular science, just years of me being a weather enthusiast. I think if this northerly does make it successfully to our shores and hangs around a few days then we’re in with a shot of the cold becoming embedded especially if there’s a fair amount of snow cover. This is what happened in 81 and it took until after Christmas until the Atlantic made inroads. 

[Met4Cast]

The 18z GEFS are actually more strongly clustered towards the colder options vs the 12z GEFS run.

The det might be all over the place but overall I'd say it's an improvement.

[BLAST FROM THE PAST]

It’s over….no doubt about it…it’s over…….barr the 18z….which shows that a daily run means diddly squat.  I read John Holmes’ post earlier today….many must have….and to me the ‘singular’ very changeable gfs rubs are garbage.

nothing is sorted yet, details are certainly not bagged….and raging SW’lies are way down the list

 

BFTP

[kold weather]

Just now, Met4Cast said:

The 18z GEFS are actually more strongly clustered towards the colder options vs the 12z GEFS run.

The det might be all over the place but overall I'd say it's an improvement.

Big difference is they are far more keen to keep the low towards the SE rather than swinging it up through England, means a great many more runs pull in colder air again behind, a few tight enough to probably cause a rain-snow event even in the far south.

Most runs have a big snow event somewhere, has to be said mainly wet for the south mind you until some pull colder air back in. Then it becomes a roulette again with the hopes of slider lows/Scandi wedges. Quite a plausible evolution imom

[Ben Sainsbury]

10 minutes ago, Scott Ingham said:

It’s the childishness that I can do without. Thanks again for the kind words mate I also enjoy your content btw  you’ve brought something good to this forum this year

I second what everyone else is saying in that your posts are very insightful Scott and always greatly appreciated! Who cares about those who can't appreciate posts, they're irrelevant. We're all here for the same reason and that's to discuss our beloved weather.

As you can imagine work is quite busy at the moment, but looking at the models it seems like around T120 is a key point at the moment. It's whether that initial push of heights towards Greenland is sufficient to set-up that northerly which then precedes the frontal rain/sleet/snow at Day 7. GFS consistently fails with that initial push and the resultant boundary of rain/snow is further north. The majority of the other OP models have a stronger initial push of heights towards Greenland which manage to hold, allowing colder air to get in place before the slider low moves across Southern UK. I feel we are on the right side of the boundary at the moment, but that may well change so will be interesting to watch.

[Paul White.]

6 minutes ago, Scott Ingham said:

How do I block on here? I’m trying now

https://community.netweather.tv/ignore/

 

its a vital tool 

[BLAST FROM THE PAST]

24 minutes ago, Scott Ingham said:

I didn’t get the Scott Ingham day full stop I found it a little embarrassing as I’m just a weather enthusiast tbh Phil! But if a forecast comes off why would you not be enthusiastic about it when you’re learning. This place is a my d*** is bigger than yours atmosphere n i just care about the science only! I’ll get more wrong than right!!

Told you to say 14-16 approx rather than 15th.  Scott, don’t worry about the doomsayers, still a week to go and look at 18z compared to earlier runs …..the game is STILL ON.  You made the call, you stick by it….due to the science you’re learning and for me it’s a hit no matter longevity which I’m sure tomorrow will look mire potent than today…

 

BFTP

Edited January 9 by BLAST FROM THE PAST

[ScottSnow]

4 minutes ago, BLAST FROM THE PAST said:

It’s over….no doubt about it…it’s over…….barr the 18z….which shows that a daily run means diddly squat.  I read John Holmes’ post earlier today….many must have….and to me the ‘singular’ very changeable gfs rubs are garbage.

nothing is sorted yet, details are certainly not bagged….and raging SW’lies are way down the list

 

BFTP

I’ve just looked at the GFS 18z and thought exactly the same. People will be saying it’s the best model out there now.

To me we are still just looking at the general pattern coming up, which is still promising across all of the models. 

Still a few days to go until we can even nail down what’s going to happen at the start of next week.

Very exciting model watching at the moment.

[Scott Ingham]

6 minutes ago, Ben Sainsbury said:

I second what everyone else is saying in that your posts are very insightful Scott and always greatly appreciated! Who cares about those who can't appreciate posts, they're irrelevant. We're all here for the same reason and that's to discuss our beloved weather.

As you can imagine work is quite busy at the moment, but looking at the models it seems like around T120 is a key point at the moment. It's whether that initial push of heights towards Greenland is sufficient to set-up that northerly which then precedes the frontal rain/sleet/snow at Day 7. GFS consistently fails with that initial push and the resultant boundary of rain/snow is further north. The majority of the other OP models have a stronger initial push of heights towards Greenland which manage to hold, allowing colder air to get in place before the slider low moves across Southern UK. I feel we are on the right side of the boundary at the moment, but that may well change so will be interesting to watch.

Really appreciated Ben!

4 minutes ago, BLAST FROM THE PAST said:

Told you to say 14-16 approx rather than 15th.  Scott, don’t worry about the doomsayers, still a week to go and look at 18z compared to earlier runs …..the game is STILL ON.  You made the call, you stick by it….due to the science you’re learning and for me it’s a hit no matter longevity which I’m sure tomorrow will look mire potent than today…

 

BFTP

Thanks mate I’d understand it if I was the met office or something but I’m an amateur finding my way!!

[ghoneym]

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[The Enforcer]

49 minutes ago, Richard Fisher said:

Why is the border between snow and rain always the M4? Is this by chance or is there a geographical explanation why this happens a lot?

It's a myth. My location is north of there and it usually rains in borderline situations.

[Ladyofthestorm]

23 minutes ago, BLAST FROM THE PAST said:

It’s over….no doubt about it…it’s over…….barr the 18z….which shows that a daily run means diddly squat.  I read John Holmes’ post earlier today….many must have….and to me the ‘singular’ very changeable gfs rubs are garbage.

nothing is sorted yet, details are certainly not bagged….and raging SW’lies are way down the list

 

BFTP

I hope your leg pulling. Lol

Potentially we have some pretty good conditions for snow, I would bet on it even in the South. 

There is absolutely nothing in the teleconnections to suggest anything mild at all . 

We have an elongated PV and it's suffering big time. I'm suspecting we will see a technical SSW finish the job like 2013 soon. 

[Weather Monkey]

I took a gander at the Model Discussion Thread back in late December 2009 to see how things compared. The discussions were quite similar to the last few days here but one thing I noticed, and l do remember from lurking back then, was having model agreement at 96hrs. This morning I highlighted comments from the pros over the pond in the NCEP discussion that "The UKMET was removed on day 4 due to its significant divergence from the rest of the guidance regarding the shortwave energy in the East Pac/Northwest U.S." Day 4 is of course 96h. 

So, where are we at as things stand at 72h and 96 hours from today's runs?  Are the models in agreement at this early juncture?

ECM 

+72h

+96h

EC Mean
+72h

+96h

GFS (I could only get the 18z so times adjusted to 66h & 90h accordingly)

+66h

+90h

GFS Mean

+66h

+90h

UKMO
+72h

+96h

GEM

+72h

+96h

And because IanF used to mention the JMA, here they are for the same time frames.

JMA

+72h

+96h

Finally we have the MetO faxes. The 84h+ hadn't updated on Meteociel when I looked so we can directly compare Sat 12z.

9.1 12z +72h

9.1 0z +84h

9.1 0z +96h 

And as a bonus here's tonight's ECM Op run in gif form.

The EC Op looks appears so well supported by the Mean that I had to check I hadn't saved the image twice. As for the rest, they have similarities at 72h but more differences by 96h. Events over the pond at that short timeframe make it difficult to call. Fascinating to watch though. 

Edited January 10 by Weather Monkey
To tidy up and remove extra images at end

[MATTWOLVES 3]

1 hour ago, Wilko999 said:

Cherry picking season again. Every time it's not favourable it's discounted. same old same old in here then. 

Your missing the point mate..its not cherry picking,me and a few others are stating that GFS as been largely on its own,that's not to say its completely wrong either. Ecm ukmo mogreps for instance all seem to go against it! It appears the met go against it as well,so do we accuse them of cherry picking cause that model is not showing the outcome they think is most likely!

The tweets from Amy Butler also points out how she sees Greenland blocking to gain some traction next week due to the recent warming! Again gfs seems to go against this also! And trust me she's a dam good scientist. It also points out how the strat is potentially coming under further rounds of warming looking ahead...so models will again struggle until this is resolved,yet it appears gfs is struggling more than others.

In all honesty I can understand why @Scott Inghamloses his rag at times because some can't see the woods for the trees. Its getting to the point that if 6 models all went cold,yet just one gfs went against it some would still say im not liking this trend one bit...its all going wrong..we can never get a cold spell in the uk anymore..next year im going on holidays to Finland...the list goes on.

Op runs are but one run amongst 30 members on gfs,and 1 of 50 on the ecm model. Yet some call the outlook on that one run before even viewing all the other data! Im not having a dig at the masses on here,cause the best posters know this and will want to view all the data over numerous runs and over several days before making a call or changing there minds. So I would call cherry picking a situation when 90% of the data goes one way with only that small cluster of 10% showing something more favourable being the one that gets pointed out for favouritism...not the other way around.

[Ladyofthestorm]

1 minute ago, Weather Monkey said:

I took a gander at the Model Discussion Thread back in late December 2009 to see how things compared. The discussions were quite similar to the last few days here but one thing I noticed, and l do remember from lurking back then, was having model agreement at 96hrs. This morning I highlighted comments from the pros over the pond in the NCEP discussion that "The UKMET was removed on day 4 due to its significant divergence from the rest of the guidance regarding the shortwave energy in the East Pac/Northwest U.S." Day 4 is of course 96h. 

So, where are we at as things stand at 72h and 96 hours from today's runs?  Are the models in agreement at this early juncture?

ECM 

+72h

+96h

EC Mean
+72h

+96h

GFS (I could only get the 18z so times adjusted to 66h & 90h accordingly)

+66h

+90h

GFS Mean

+66h

+90h

UKMO
+72h

+96h

GEM

+72h

+96h

And because IanF used to mention the JMA, here they are for the same time frames.

JMA

+72h

+96h

Finally we have the MetO faxes. The 84h+ hadn't updated on Meteociel when I looked so we can directly compare Sat 12z.

9.1 12z +72h

9.1 0z +84h

9.1 0z +96h 

And as a bonus here's tonight's ECM Op run in gif form.

The EC Op looks appears so well supported by the Mean that I had to check I hadn't saved the image twice. As for the rest, they have similarities at 72h but more differences by 96h. Events over the pond at that short timeframe make it difficult to call. Fascinating to watch though. 

Fabulous post! 

[Daniel*]

1 hour ago, GokouD said:

These GFS runs seem to be pushing an insane amount of cold down into the US, I bet they're cheering for it over there. It seems a bit OTT to be true though...

No, major cold outbreak on way in coming days. 

[The Enforcer]

3 hours ago, Mike Poole said:

A novel forecasting method, yours, I’ll give you that.  Interesting that the percentage of stinkers thrown out should be roughly inversely proportional to my estimate of the reliability of the ensemble suite.  Offers a clue as to where the truth lies…

GEFS18z back down to 28% stinkers (excluding the operational and control), same as 00z, better than 06z and 12z.

Edited January 10 by The Enforcer

[Wold Topper]

Wow guys, just read 12 pages after work, sad i know! Fascinating the dedication from some posters, hope Scotts ok.....

[Cold Winter Night]

1 hour ago, LRD said:

Ha ha!

Yes to be fair Scott and a couple of others did call the potential for a scandi ridge last week. I think you might have mentioned something too. It's only one run of course and longer term models like EC46 haven't picked up on that yet. Probably a phantom in the GFS machine again but let's see if it's somehow latched on to something

That's not really true. For more than at least a week the EC46 ensemble mean attribution (bottom of the chart) for end of January - into February has consistently been Scandi blocking, so good signs from that corner.

Edited January 10 by Cold Winter Night
Added chart

[jacke]

1 hour ago, MATTWOLVES 3 said:

Your missing the point mate..its not cherry picking,me and a few others are stating that GFS as been largely on its own,that's not to say its completely wrong either. Ecm ukmo mogreps for instance all seem to go against it! It appears the met go against it as well,so do we accuse them of cherry picking cause that model is not showing the outcome they think is most likely!

The tweets from Amy Butler also points out how she sees Greenland blocking to gain some traction next week due to the recent warming! Again gfs seems to go against this also! And trust me she's a dam good scientist. It also points out how the strat is potentially coming under further rounds of warming looking ahead...so models will again struggle until this is resolved,yet it appears gfs is struggling more than others.

In all honesty I can understand why @Scott Inghamloses his rag at times because some can't see the woods for the trees. Its getting to the point that if 6 models all went cold,yet just one gfs went against it some would still say im not liking this trend one bit...its all going wrong..we can never get a cold spell in the uk anymore..next year im going on holidays to Finland...the list goes on.

Op runs are but one run amongst 30 members on gfs,and 1 of 50 on the ecm model. Yet some call the outlook on that one run before even viewing all the other data! Im not having a dig at the masses on here,cause the best posters know this and will want to view all the data over numerous runs and over several days before making a call or changing there minds. So I would call cherry picking a situation when 90% of the data goes one way with only that small cluster of 10% showing something more favourable being the one that gets pointed out for favouritism...not the other way around.

Right on Matt, now get to bed lol.

[Penrith Snow]

3 hours ago, Bristawl Si said:

Partly, at least

Topography

A few miles north of the M4, from near here i.e. Old Sodbury, near the Bath M4 junction right along to past the Swindon junctions, we have the start of the Cotswolds or its escarpment.

Example: Heights go from 80m ASL in Yate, for example, to 150m plus, a mile or so 'up the road' In Old Sodbury. This happens all the way along the M4 to past Swindon.

Further East, past Reading, north of the M4, is the Chilterns, highest point 260m ASL.

It's an odd fact that at the height of the last glaciation the main Scandinavian Ice Sheet covered Britain right down to a line from the Bristol Channel to Thames Estury, (now the M4 corridor) the southern half of England below this line remained free of ice and was tundra instead.

Coincidence I know but interesting nevertheless 

Andy

[stewfox]

GFS oz rolling out now 

At 138 hrs 0z first and 18z second 

Colder air over all of Eire

 

Edited January 10 by stewfox

[Battleground Snow]

Still no agreement at 120.

Ukmo the cleanest northernly still