Model output discussion - cold spell approaching?

[sheikhy]

1 minute ago, Battleground Snow said:

Para top image.. OP bottom for 48 hours

Hows the band looking on para?more widespread at 36 hours?

[Battleground Snow]

1 minute ago, sheikhy said:

Hows the band looking on para?more widespread at 36 hours?

Yes alot more widespread, arome is probably my go to model closely followed by Harmonie and arpege

[Kasim Awan]

1 minute ago, Battleground Snow said:

Yes alot more widespread, arome is probably my go to model closely followed by Harmonie and arpege

The GFS Op is wrong, the most likely scenario is 1-3 hours of heavy snow to lower levels across the North Midlands & Northern England, potentially also the central Midlands later. Let's see how long it takes the UKMet to catch up on this.

[bluearmy]

Seriously guys - are we really saying that an area will get plastered with snow with the stalling front and undercut from the east ???

it’s so completely uncertain away from the high ground in ne England and e Scotland 

[Battleground Snow]

1 minute ago, Kasim Awan said:

The GFS Op is wrong, the most likely scenario is 1-3 hours of heavy snow to lower levels across the North Midlands & Northern England, potentially also the central Midlands later. Let's see how long it takes the UKMet to catch up on this.

They will adjust it south for sure, by how much is the question, it will be around 11am after all the 06z data has been digested

[chris55]

Seeing as we are getting small, but significant changes very early in these runs, could these early differences have significant knock on impact as the runs progress, or are they to insignificant to impact the larger broad scale pattern?

Its and interesting point of view, and for me I will hold back on being to confident on the extended forecasts (even the means) until the shorter term becomes a little less volatile. Might just be wishful thinking but that's my tactic lol.

 

 

[sheikhy]

Just now, Battleground Snow said:

They will adjust it south for sure, by how much is the question, it will be around 11am after all the 06z data has been digested

Para gives around 6 hours of snowfal for the midlands!!!!

[Vikos]

Some changes even in closer range

Edited January 13, 2021 by Vikos

[I remember Atlantic 252]

3 minutes ago, Kasim Awan said:

The GFS Op is wrong, the most likely scenario is 1-3 hours of heavy snow to lower levels across the North Midlands & Northern England, potentially also the central Midlands later. Let's see how long it takes the UKMet to catch up on this.

FAX for midday,

[NewEra21]

Just now, Vikos said:

Some changes even in closer range

My eyes are not quick enough to keep up with that

[Kasim Awan]

3 minutes ago, Battleground Snow said:

They will adjust it south for sure, by how much is the question, it will be around 11am after all the 06z data has been digested

How much the Met adjusts it south has absolutely no bearing on where I think it will snow. If the front manages to loose organization which is what is bringing down the snow-line from the 300-400m base then it will be restricted to hills, however this at present is only a very low risk with only the GFS Op hinting at this. A line from Peterborough, to Nottingham, Derby to Leeds most at risk from the heavy falling snow 1-4cm here to lower levels, perhaps even further south than this though the uncertainty line stops at Birmigham / Luton at present. Warrants a warning imo purely because of how fast the snow will fall, not the amounts.

Edited January 13, 2021 by Kasim Awan

[Tim Bland]

4 minutes ago, bluearmy said:

Seriously guys - are we really saying that an area will get plastered with snow with the stalling front and undercut from the east ???

it’s so completely uncertain away from the high ground in ne England and e Scotland 

It’s certainly possible ! Looking at all the high res models East Midlands up to the north east are in for a dumping, perhaps even chilterns as well. According to the UKV it could happen twice - As it shows even heavier snow in similar places on Sat!

[Vikos]

1 minute ago, NewEra21 said:

My eyes are not quick enough to keep up with that

updated

[Battleground Snow]

Back to the future.... And the GFS op is a marginal improvement with the Greenland ridge at 138

[snowy owl]

If we have ongoing SSW responses still coming through will this have any effect on the west based -NAO? 
 

 

Edited January 13, 2021 by snowy owl

[Vikos]

+144 00z/06z, this polar high is stretching....

[BLAST FROM THE PAST]

 

00z t162

 

06z t156

Subtle differences but overall theme the same.  

BFTP

Edited January 13, 2021 by BLAST FROM THE PAST

[mushymanrob]

Sorry if this chart has been posted, theres over 20 pages to trawl through since i last logged on and theres not enough time in the day to go through that lot!

A couple of days ago i posted an anomaly chart suggesting that there was no deep cold on it, and was then asked what to look out for, to which i replied the green contour lines from a more northerly direction.

Well here you are.... the green lines over the UK are sourced from Greenland, theres a slack flow to our Northeast low to our near East and the milder flow is well to our South into Biscay.

Low pressure to our near East, Northerly sourced air, thats got to produce snow surely!

The 8-14 day chart is the same, more or less, but the only fly in the ointment is that these charts have swung rather abruptly, so are not consistent, so if tonights output is more or less the same then confidence must be high that these charts are showing the most probable general synoptic pattern.

 

[KTtom]

Has snow potential been replaced with storm potential for next week?

[Kasim Awan]

2 minutes ago, KTtom said:

Has snow potential been replaced with storm potential for next week?

Yes, just looks like a mobile Greenland high & incursions of Polar Maritime air up to 170 hours at least.

[nick sussex]

You need a 24 hour delay to any phasing otherwise that will cause a ne push and delay any cold .

And the phasing blows up low pressure over the UK and pushes the cold even further to the west .

There’s still some hope if the block can remain trapped and not escape and the Arctic high continues to add some forcing onto the troughing but at the moment this first attempt looks like being a washout rather than a white out .

So best to lower expectations and see whether later on things might fall more kindly .

[Djdazzle]

3 minutes ago, KTtom said:

Has snow potential been replaced with storm potential for next week?

One thing is for sure - there is very little in that chart in terms of snow.

[Battleground Snow]

3 minutes ago, KTtom said:

Has snow potential been replaced with storm potential for next week?

You would hope the GFS is overblowing them as usual and they track further South

[Weathizard]

Phasing Atlantic lows, story of our winter.

[Battleground Snow]

1 minute ago, Weathizard said:

Phasing Atlantic lows, story of our winter.

The para looks more realistic with weaker features, it's still not a great chart for cold fans tho

Edited January 13, 2021 by Battleground Snow