Model output discussion 25th Jan - The final third of winter beckons..

[snowray]

1 hour ago, Seasonality said:

Matt Hugo's post is factually correct. It isn't a full on blast of an easterly for the UK and not in the same vein as 1991 or 1987. Doesn't mean it won't be chilly or not snow.

Ok, no 91 or 87, I don't mind it being a close third to them two. In fact I'd be very happy with that thanks.

 

Cold gets in a bit earlier on this run, Atlantic marginally further west.

[Daniel*]

T90 slightly more latitude on the Scandi block. Heights to the SW look slightly less imposing too.

[Seasonality]

2 minutes ago, Hammer said:

The cold pool 850's look slightly deeper and closer to east coast at same time frames from even the 6z. Assuming a good thing?

Yes. A slight deepening of cold and westwards progression. That is what the UK "needs." Meanwhile surface temps further east in Europe are 3 degrees colder in my location than forecast even yesterday. Good news for any westwards movement of the cold air.

[Seasonality]

Just now, snowray said:

Ok, no 91 or 87, I don't mind it being a close third to them two. In fact I'd be very happy with that thanks.

 

Cold gets in a bit earlier on this run, Atlantic marginally further west.

Indeed. A repeating pattern of overestimating the Atlantic.

[SteveB]

2 minutes ago, More Snow said:

he has been speaking all winter and mostly he has been way off the mark...

He's been calling it as the models show it, and we know the models change each and every time!

[Ali1977]

The Atlantic front is slightly NW/SE, last run it was slightly NE/SW, may help with an undercut or slight one!!

[SMU]

The 12z theta charts say it all -

Whilst the 500s arent as revealing

06z To 12z a 2c degree drop & a pool of 4 degree drops .

[radiohead]

At T126, uppers on the east coast are -6 on the 12Z where they were -10 on the 06Z...

[SMU]

Good afternoon so far

UKMO 120

Italian low deeper & further North- & whats that? - The high is shaped so acute now up to the pole - the second deep upper air cold pool is starting to move Sw..

Winds straight easterly on UKMO from 96-

[snowray]

14 minutes ago, Seasonality said:

Indeed. A repeating pattern of overestimating the Atlantic.

UKMO even better.

[That ECM]

Ukmo at t144 is quality. Much further west than gfs.

[Iceberg]

Remarkably different n.hemi details on this 12z run compared to the last few gfs runs in a critical timeframe. Far more like the meto profile. 

Too early to say for sure but this (could) be the start of a change away from too much energy over the top of the high from t168 onwards 

[Mucka]

Just now, snowray said:

UKMO even better.

Yes that is a better chart for getting the cold uppers across the UK. May be fairly short lived though with energy looking like heading NE from there.

[Frosty.]

Just now, That ECM said:

Ukmo at t144 is quality. Much further west than gfs.

Hopefully setting up a prolonged spell of entrenched cold, great start to the 12z's

[Daniel*]

Immaterial to the uppers GFS 12z bigger picture a lot better compared to 06Z. A firmly grounded Scandi high & Azores high is more displaced away from us! 

Still need improvements... But better.

Edited February 4, 2017 by Daniel*

[PersianPaladin]

1 minute ago, Iceberg said:

Remarkably different n.hemi details on this 12z run compared to the last few gfs runs in a critical timeframe. Far more like the meto profile. 

Too early to say for sure but this (could) be the start of a change away from too much energy over the top of the high from t168 onwards 

Indeed, but as ever - the problem of too much energy in the southern arm (linked with a high amplitude upper trough from Greenland) will inevitably bring in flatter ridging from the Atlantic Azores and milder air.

[That ECM]

2 minutes ago, Frosty. said:

Hopefully setting up a prolonged spell of entrenched cold, great start to the 12z's

It's a shame we don't get the 850's for ukmo but I guess it stops this place going to ramp mode. They would be very good imo.

[Frosty.]

1 minute ago, That ECM said:

It's a shame we don't get the 850's for ukmo but I guess it stops this place going to ramp mode. They would be very good imo.

I'm really happy with the model trend now that the pros have rubber stamped a prolonged cold spell..seasonal models must be even better!

[Paul_1978]

Not meaning to be negative but by T+180 we are getting back into SW'lys, and we have been seeing the GFS repeat this trend in the last few runs.... that's making me more than a bit nervous. 

[Iceberg]

3 minutes ago, PersianPaladin said:

Indeed, but as ever - the problem of too much energy in the southern arm (linked with a high amplitude upper trough from Greenland) will inevitably bring in flatter ridging from the Atlantic Azores and milder air.

Yes. It's only a start but at least it's started the journey rather than continuing in the opposite direction. 

Good that uk gm takes the step as well we just need to see ec take the step. 

Ec will certainly flatten the high but the arctic profile and AH might start to improve. 

[Ali1977]

1 minute ago, Frosty. said:

I'm really happy with the model trend now that the pros have rubber stamped a prolonged cold spell..seasonal models must be even better!

The GFS isn't good beyond 180, but I guess it trended slightly better earlier on - wouldn't take a great change earlier on to actually stop the Atlantic. Not this run though. The UKMO better at 144 but unsure if it will hold, but again it's better than earlier. We need to see some ENS stay cold, then we may get an idea of how it could happen.

[Zakos]

Facsinating model watching. Lovely to see the forum buzzing again just as the chase for cold died off.                                                                                                                                                                       .                                                                                                                                                                                                                                                                                                          The block has only just started to advance west across Scandinavia. Such a process is not going to be handled well by the models, and as such there are going to be wild swings in the output. By far the most promising event of winter. Based on how blocked the Atlantic has been for several months now, I think we are in for a prolonged cold spell here. Fingers crossed.

Edited February 4, 2017 by Zakos

[mcweather]

Seen enough this afternoon to call it an upgrade in the reliable.  no point at all looking beyond 144 at the moment because the model that has called it right all winter the Meto only goes out that far (publicly) and it looks the best of the lot again today.

[Frosty.]

Just now, Ali1977 said:

The GFS isn't good beyond 180, but I guess it trended slightly better earlier on 

 

That's the important thing, trended better earlier and hopefully that will continue..great to see SM so positive, it's a good indicator for a decent cold spell..long may it last!

[Iceberg]

Look at the profile change around the Kara sea. 

It's a nice barometer of how the energy over the high has changed. A small switch and we get a strong high building pushing any energy over the pole. 

This is far from over.