Model output discussion - 7th January onwards

[Ben Sainsbury]

7 minutes ago, weirpig said:

Different on the ICON 12z at 120h onwards  trough seems to be still attached to the diving low   will it make any difference??.

I feel like once the low does dive SE'wards, we may see *possibly* the Canadian vortex move towards the UK a little earlier. 

Edited January 14, 2019 by Ben Sainsbury

[ICE COLD]

Just now, Ben Sainsbury said:

I feel like once the low does dive SE'wards, we may see *possibly* the Canadian vortex to move towards the UK a little earlier. Just guessing as we cannot go past +120.

The icon 12z run goes to T180 mate .

[karlos1983]

This is much better from the ICON, chance of further lows heading SE rather than flattening out the pattern 

The difference is huge from it's 06z

12z / 06z

Edited January 14, 2019 by karlos1983

[Ben Sainsbury]

2 minutes ago, ICE COLD said:

The icon 12z run goes to T180 mate .

My mistake I totally forgot!

[northwestsnow]

1 minute ago, karlos1983 said:

This is much better from the ICON, chance of further lows heading SE rather than flattening out the pattern 

Lets hope its a portent of things to come matey

[weirpig]

Well  it may not be a dumping  but the low on the ICON does bring snow for some   through the Country Midlands North      and to be honest that will do for most in what has been a barren winter 

         

Edited January 14, 2019 by weirpig

[karlos1983]

1 minute ago, northwestsnow said:

Lets hope its a portent of things to come matey

Unfortunately it gets scuppered by another Low head out of the esb which flattens the pattern towards the end of the run.. But all the same, a good start to the 12z..

[MidnightSnow]

Apologies in advanced for the newbie question:

If the lobe over Canada does reach the UK, what weather would that bring? Or is that impossible to answer? 

[weirpig]

Arpege different at 114h  trough heading south East  

[karlos1983]

UKMO not budging! But as well discussed, it's what follows that is of importance.

12z +96 vs 00z +96 

Edited January 14, 2019 by karlos1983

[Tristrame]

10 minutes ago, MidnightSnow said:

Apologies in advanced for the newbie question:

If the lobe over Canada does reach the UK, what weather would that bring? Or is that impossible to answer? 

Too much modification on a long transatlantic journey over relatively warm water would mean rain probably away from Scottish and northern hills

Unless said low passed south of Ireland,in which case less modified colder air would follow from a more north northeasterly quadrant in its wake

Then you'd be talking winter

 

Edited January 14, 2019 by Tristrame

[bluearmy]

10 minutes ago, MidnightSnow said:

Apologies in advanced for the newbie question:

If the lobe over Canada does reach the UK, what weather would that bring? Or is that impossible to answer? 

Impossible to answer without understanding the context of how it arrives and in what form it is once it arrives 

[WhiteFox]

9 minutes ago, MidnightSnow said:

Apologies in advanced for the newbie question:

If the lobe over Canada does reach the UK, what weather would that bring? Or is that impossible to answer? 

Unsettled!

Low temperatures would be modified upwards by the journey over a much warmer ocean and mixed out by interaction with warmer air being dragged in form the south, but actual values would depend on how quickly it moved across, and the direction of travel. It doesn't happen very often, but a few forecast charts have shown such an event recently, and it gave 850 temps of around -6 or so (as a guestimate) which would probably result in rain/sleet/snow for higher ground and further north. As a general summary anyway...

[shaky]

Incredible consistency in regards to the slider from ukmo!!

[seabreeze86]

1 minute ago, shaky said:

Incredible consistency in regards to the slider from ukmo!!

Yeah and now at 120hrs, surely can't be wrong at 120 hrs the UKMO can it???

[frosty ground]

3 minutes ago, shaky said:

Incredible consistency in regards to the slider from ukmo!!

GFS showing the same consistency albeit with a correction west slightly (Of the uppers).

Edited January 14, 2019 by frosty ground

[Glacier Point]

So here's where it feels like we're playing meteorological Russian roulette, only the bullet is a marked step change in the hemispheric circulation towards a -AO / -NAO regime.

Control run 06z GEFS goes from this ..

To this ...

In the space of 6 days. 

The Control has the same data as the operational, so it's not a question of data differences, rather resolution although at that range resulting in differences between ops and control. High resolution on a broad scale change isn't necessarily a good thing.

GFS Northern Annular Mode projection, in line with AO forecasts, suggesting strat downwelling now coming into view.

MJO also arriving in phase 7 at the same time, which would be conducive to blocking formation.

 

[Chris K]

3 minutes ago, seabreeze86 said:

Yeah and now at 120hrs, surely can't be wrong at 120 hrs the UKMO can it???

I have found that in the past, when we get scenarios likes this, there is generally a movement towards a middle-ground solution over the next 4-5 days. However until all main models agree it is difficult to judge.

Edited January 14, 2019 by Chris K

[shaky]

3 minutes ago, frosty ground said:

GFS showing the same consistency albeit with a correction west slightly (Of the uppers).

Yup but those colder uppers have been pushing more and more west throughout the day and that slider is being modelled further west with each run!!gfs could be a fail in that sense!!

[booferking]

UKMO vs GFS who wins we all know were the money goes..

[mountain shadow]

Just now, booferking said:

UKMO vs GFS who wins we all know were the money goes..

Whilst there are differences, surely the weather at the surface will be the same? Cold rain for most away from the hills and North Eastern areas of Britain?

[swfc]

1 minute ago, booferking said:

UKMO vs GFS who wins we all know were the money goes..

Wins what tho???? it will flatten out like gfs going forward.This wont stop the energy to the north west pushoing threw in that time frame

[frosty ground]

Next low coming around the high at 144 on UKM

Milder sector would be noticeable backs the GEFS uptick in temps. 

[frosty ground]

1 minute ago, mountain shadow said:

Whilst there are differences, surely the weather at the surface will be the same? Cold rain for most away from the hills and North Eastern areas of Britain?

Well the low is further west on the UKM so the colder air will be to. The direction of travel beyond day 6 is clear but not sure there is no snow to be had from the UKM chart.

[frosty ground]

All of a sudden the GFS looks better for beyond day 7 with day 5 also producing more snow for the midlands northwards.