Cold hunt - models and chat

[AWD]

Looks like some more hill snow for the north on Sunday, on the UKMO 12z;

Edited January 22, 2019 by AWD
Wrong day

[Johnp]

Things seem to be accelerating towards cold now.

UKMO looks a couple of days from an easterly again at 120hrs

[chionomaniac]

Please keep local reports and snow reports to the local threads. I know that this is a more relaxed thread now but it is still model related. Thanks

[nick sussex]

I think the SSW downwelling is beginning to cause havoc with the modelling .

The more influential Russian high has returned on the UKMO which it had last night but dropped this morning.

[fromey]

3 minutes ago, Johnp said:

Things seem to be accelerating towards cold now.

UKMO looks a couple of days from an easterly again at 120hrs

the high in the atlantic looks like is heading north plus the russian/scandy high is a bit more robust.

 

[shaky]

5 minutes ago, nick sussex said:

The higher resolution GFS brings a little shortwave south at 36 hrs , this brings an area of rain, sleet and snow .

This has just popped up and wasn’t on earlier runs because the low to the nw disrupts a bit more .

Guess what nick euro4 had it but over the north west england and west mids but i thought it was am outlier due to no other model showing it!!the cold is defo putting up more of a fight!!

[Weathizard]

1 minute ago, nick sussex said:

I think the SSW downwelling is beginning to cause havoc with the modelling .

The more influential Russian high has returned on the UKMO which it had last night but dropped this morning.

Indeed, hopefully it’s from Russia with love this time as that Russian high can be a nuiscance if not positioned correctly.

[Rocheydub]

1 minute ago, nick sussex said:

I think the SSW downwelling is beginning to cause havoc with the modelling .

The more influential Russian high has returned on the UKMO which it had last night but dropped this morning.

My thoughts exactly Nick. And (dare I say it) it can accelerate colder outputs in the nearer frame. There is definitely a hint of heights and weakening low pressure systems north of us with every passing chart. Maybe a wee short term surprise too.

[Weathizard]

UKMO looking decently primed at 144, positive so far.

[AWD]

UKMO 144:

Run through the whole run and you'll notice the Canadian vortex slowly draining out of the states.  Would be nice if this could continue and lift out of Canada too.

[shaky]

8 minutes ago, nick sussex said:

The higher resolution GFS brings a little shortwave south at 36 hrs , this brings an area of rain, sleet and snow .

This has just popped up and wasn’t on earlier runs because the low to the nw disrupts a bit more .

Where does it cross at 42 hours!!!gfs has defo backed the cold further west compared to yesterday runs!!!

[tight isobar]

5 minutes ago, AWD said:

Looks like some more hill snow for the north on Saturday, on the UKMO 12z;

Pal..

That chart/ukmo..says more than just north eng.

Thats a potentialy top snowy chart via ukmo.

Some real interest- in snowy conditions begining gain...

A snowy breakdaown..to a more notable freeze...IS FAR FROM OFF THE CARDS.

[nick sussex]

Just now, Rocheydub said:

My thoughts exactly Nick. And (dare I say it) it can accelerate colder outputs in the nearer frame. There is definitely a hint of heights and weakening low pressure systems north of us with every passing chart. Maybe a wee short term surprise too.

Yes the PV is also imploding on the UKMO .

The differences at day 4 suggest the models are all over the place . And good point re those low pressures to the nw .

The PV which has been feeding them is beginning to deflate !

[nick sussex]

1 minute ago, shaky said:

Where does it cross at 42 hours!!!gfs has defo backed the cold further west compared to yesterday runs!!!

Try the GFS 0.25 you can see it develops a small circulation as it runs south , it’s a shallow feature.

And it does show a mix of  precip.

[Johnp]

Progressing frame by frame I think we are starting to see signs of the downwelling now,with low pressure systems not progressing as you might expect - almost as if the breaks are being applied by an invisible force.

Either that or someone's spiked my cup of tea.

[chionomaniac]

10 minutes ago, chionomaniac said:

Please keep local reports and snow reports to the local threads. I know that this is a more relaxed thread now but it is still model related. Thanks

It takes less than 5 minutes for someone to ignore this. The best moderation is self moderation......

[AWD]

3 minutes ago, tight isobar said:

Pal..

That chart/ukmo..says more than just north eng.

Thats a potentialy top snowy chart via ukmo.

Some real interest- in snowy conditions begining gain...

I'm not seeing that mate;

[tight isobar]

Gfs 12z..moves inline with ukmo...

And as again we have ample snow chances..

As features are noted and uppers are of favour...

[frosty ground]

1 minute ago, AWD said:

I'm not seeing that mate;

Not even for the North of England

[tight isobar]

3 minutes ago, AWD said:

I'm not seeing that mate;

Not on the 850 notion agreed..

But with the relaxi g jet prof-and the pushing wedge of milder sector..

A much more proununced shot of deeper minus uppers are of worthy note.

And is as usual playout @this time frame b4..we align..and note as again a better microsacle sbot..@the mentioned 850hpa's

Edited January 22, 2019 by tight isobar

[Weathizard]

Rather different UKM and GFS at day 6, Shannon entropy looks to be rearing her mush again.

[AWD]

Just now, frosty ground said:

Not even for the North of England

I did say "hill snow for the north" purely because the colder 850hpa temps do quickly come down just after the weekend;

So something wintry possible as Sunday progresses into Monday for Scotland and the Pennines.

[nick sussex]

The GFS and UKMO disagree as early as day 3 with the set up to the north .

And by day 4 huge differences . So detail wise only short term is possible .

 

[Panayiotis]

3 minutes ago, Weathizard said:

Rather different UKM and GFS at day 6, Shannon entropy looks to be rearing her mush again.

The biggest difference for me is the amount of energy over Greenland! Will be interesting to see what the GFS does regarding any block over Greenland in the later stages 

[pureasthedriven]

1 minute ago, Panayiotis said:

The biggest difference for me is the amount of energy over Greenland! Will be interesting to see what the GFS does regarding any block over Greenland in the later stages 

Yes. I’d prefer those models the other way round, frankly.