Model output discussion - mid-winter

[nick sussex]

I think for the timebeing the ECM is the outlier solution.

The others are more progressive and even though we see differences earlier the end point still currently looks the same with troughing heading over the UK.

The upstream pattern is just too flat at the key timeframe so its an uphill struggle from early doors.

 

[SMU]

Maybe the models are struggling with the massive Easterly that’s about to appear tomorrow @ 168 / 192

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[Mucka]

 

 

Edited January 14, 2018 by Mucka

[shaky]

3 minutes ago, Steve Murr said:

Maybe the models are struggling with the massive Easterly that’s about to appear tomorrow @ 168 / 192

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Oh not this again steve???!!i do genuinely think theres further changes to come though!

[Man With Beard]

34 minutes ago, Draig Goch said:

ECM 12z takes a more northerly track 

Fair agreement on the strength of the storm between ECM, GFS and ARGEPE - main area to be affected between Liverpool and Glasgow taking a straight line east between these points - gusts over 90mph on coasts/hills in the sweet spot and generally 75mph to 90mph through much of the inland area depicted above (perhaps a bit less on the east of high ground). Just slight disagreement on the track, whether closer to Glasgow or Liverpool. UKMO is the one that looks a tiny bit further south, but still strong.

Edit: forgot to mention N Ireland - here, could be even worse if deepening happens earlier

Edited January 14, 2018 by Man With Beard

[Somersetwatcher]

1 hour ago, Northern Sky said:

I'm not sure I understand this, particularly the last sentence. Looking at the latest GFS run we still have a potent PM spell - interupted for a few hours by the storm on Wed night. Yes the longevity has reduced by a day or so but in terms of the uppers and wintry potential it doesn't look much different, at least up until the weekend? 

Hi mate, yes, but in fact, the reality seems to be in line with the official met forecast which  has consistently been for nothing extraordinary or even slightly unusual for uk january weather. If you live north of Birmingham then its also normal winter fayre in the week ahead, notwithstanding any shortlived cyclogenesis and storms in the mix.

[SLEETY]

Big Easterly 1987 style  incoming on the models if you leave in ......Svalbard -28 hpa incoming

Edited January 14, 2018 by SLEETY

[Somersetwatcher]

6 minutes ago, Steve Murr said:

Maybe the models are struggling with the massive Easterly that’s about to appear tomorrow @ 168 / 192

✌️

Lol 

[Chesil View]

If we take GP's thoughts regarding the nwp models wanting to overdo the Azores high ridging into Europe days7-10. Then this is presumably because they are also mishandling developments upstream as well. So for now I'm taking all stuff beyond 120 with a huge pinch of salt

[Winter Hill]

12 minutes ago, snowray said:

ECM playing catch up and turning into a junk model very rapidly!

Been junk since its upgrade 

[johnholmes]

Regarding the marked change in the models on how the low, yet toi form in mid Atlantic, has been modelled, perhaps why there is the change?

I have no idea why the models did not go this way before when I look closely at the strong Atlantic flow and it becoming more diffluent near the UK. I have mentioned this pattern some days ago when showing the 500 mb anomaly charts. Obviously the jet is much higher, around 300 mb but the flow is, as it often is, similar in characteristics. Assuming the low forms where predicted then it is under the main jet predicted at that time but at a slight angle, moving slightly N of east. This causes it to exit the jet on its northern flank, the left exit, which you can read about if you Google, and the left exit is an area where surface features can deepen rapidly. This is due to air rising and being diverted, a very simple explanation. This causes pressure to fall at the surface, and the physics of it all causes a rapid deepening. 

For several days the anomaly charts have shown this diffluence in the UK area. When a low deepens in this area, the laws of meteorology/physics cause it to turn to the left, hence why, I think, now the models have got round to this, it is being shown with a more northerly track.

Not a perfect explanation but I hope it helps a little.

Please do look up the various things I have mentioned as I am sorry I have not got time togive a fuller explanation. If my memory serves me correctly there is something somewhere in the Net Wx Guides area.

[Mark Parsons]

I love looking in on this thread , I seldom post as my balanced view would be boring , however when the charts are showing different scenarios it proves how volitile the outcome will be and other times 2 or 3 are singing from the same song sheet and another is completely different. This week could throw up anything and the midweek storm is the catalyst for next weekend, predicting anything T96 is going to be hard in my opinion.

[karlos1983]

6 minutes ago, Broadmayne blizzard said:

If we take GP's thoughts regarding the nwp models wanting to overdo the Azores high ridging into Europe days7-10. Then this is presumably because they are also mishandling developments upstream as well. So for now I'm taking all stuff beyond 120 with a huge pinch of salt

I wouldn’t mind a GP update on this point, could have disappeared as quickly as the 5 day cold spell. 

Torpedos have gone off course before... 

his input now would be timely..

Edited January 14, 2018 by karlos1983

[igloo]

3 minutes ago, snowray said:

ECM playing catch up and turning into a junk model very rapidly!

It was the same a fortnight ago it was forecasting a easterly run after run untill it suddenly droped it on the other hand the GFS not at any stage forecasted this ghost easterly the same thing is happening again either the ECM is going downhill rapidly or the GFS has had some huge upgrades this season but the GFS is now king i feel

[nick sussex]

Oh God no! 

Please ECM, no more!

Coldies are beginning to feel like the girl out of Poltergeist. 

When she utters those words, no more!

The ECM might be about to start another wild goose chase!

[Mark Parsons]

4 minutes ago, Broadmayne blizzard said:

If we take GP's thoughts regarding the nwp models wanting to overdo the Azores high ridging into Europe days7-10. Then this is presumably because they are also mishandling developments upstream as well. So for now I'm taking all stuff beyond 120 with a huge pinch of salt

I think post T96 is sticking ones neck out Mark......

[CK1981]

One thing I have noticed with the low, it’s still very deep when it gets to the Baltics. I’m flying to Estonia on Friday, so maybe this low will actually give me some snow there?

[The PIT]

I wouldn't call any of the big three junk. It's rather amazing how they do these days compared to several years back. I think the issue possibly is looking too far ahead and expecting to much. If you look at the model scores for days five and six they are pretty good although I would still regard anything beyond T120 mainly an indicator rather than what can actually be expected.

[Cheshire Freeze]

We still won't know the path of this low for another 36 hrs or so IMO. Could be that it goes further N or comes further S in the modelling. I highly doubt nuances in pressure distribution and jet profile will be decided yet...

GEFS mean has the disturbance running across S Scotland as per Metoffice thoughts.

Edited January 14, 2018 by CreweCold

[Man With Beard]

11 minutes ago, Winter Hill said:

Been junk since its upgrade 

ECM op was the first to pick up on this storm at T192, dropped it for a few runs in been though.

[Troubleatmill]

5 minutes ago, igloo said:

It was the same a fortnight ago it was forecasting a easterly run after run untill it suddenly droped it on the other hand the GFS not at any stage forecasted this ghost easterly the same thing is happening again either the ECM is going downhill rapidly or the GFS has had some huge upgrades this season but the GFS is now king i feel

But then if the gfs had been correct we would of been under an atlantic influence all of last week, reality..as has been said before, was a blend of both and resulting was grey calm and dank. Dont think any nailed it

[Winter Hill]

10 minutes ago, Man With Beard said:

ECM op was the first to pick up on this storm at T192, dropped it for a few runs in been though.

Junk was a bit Harsh.. but it's been poor.

Imho the GfS has outperformed it. Last night's GFS 18z has started the ball rolling with today's poor outputs and The Ecm is following.

 

 

 

[Dennis]

18z 24 hours ago the worst ....today the best like this chart....

[mulzy]

32 minutes ago, igloo said:

It was the same a fortnight ago it was forecasting a easterly run after run untill it suddenly droped it on the other hand the GFS not at any stage forecasted this ghost easterly the same thing is happening again either the ECM is going downhill rapidly or the GFS has had some huge upgrades this season but the GFS is now king i feel

The verification stats clearly show that the ECMWF, though far from perfect, is clearly the superior model.  This is nothing new - well known for a number of years.

Edited January 14, 2018 by mulzy

[Winter Hill]

Just now, mulzy said:

The verification stats clearly show that the ECMWF, though far free perfect, is clearly the superior model.  This is nothing new - well known for a number of years.

But since the ECM upgraded it's not been it's superior self.