Hunt For Cold: Model Discussion - Heading Into Christmas

[Snowy L]

38 minutes ago, Steve Murr said:

As reported yesterday - this location for the ridge would be an ideal location for a QTR post SSW

 

23 minutes ago, Steve Murr said:

The 384 chart is the first run that the trop is responding to the strat split as you see a 2 wave pattern heading into the pole - one of the waves ideal for the UK

I actually think it's the high getting into that position North of the UK that causes the stratospheric split, as this is a key enhancer of wave-2. The high pressure heading North happens at day 10 then we see the strat vortex begin to split at day 13.  Finally GFS sees some pressure on the vortex from our side of the Pole.

 

Figure c is a mean of the state of the troposphere leading to a vortex split.

Edited December 20, 2018 by Snowy L

[snowray]

Lovely run......all is forgiven GFS......

Just as he was reaching for his winter supply of prozac......

Opening a bottle of prosecco instead!

[Ali1977]

11 minutes ago, karlos1983 said:

Uh oh what’s this about.....

Mmmm, whatever it is that difference in 3/4 days time doesn’t seem right - not buying it.

You’d expect to see a big split further in time not in a few days!! I haven’t seen much else about the signal , apart from the GEFS being the ones to back off slightly. Nothing to worry about. 

Edited December 20, 2018 by Ali1977

[stodge]

Afternoon all

Well, the ship has sailed for Christmas cold but the New Year, well, we'll see.

The Parallel has been consistent in splitting the PV on or about 3rd Jan and the GFS 12Z OP looks like ushering s second warming to split the PV soon after 6th Jan.

We'll also see if Amy Butler's tweet is a sign of a backtrack or just some modelling inconsistencies over the next few days.

The substantial pressure rise from the south and the subsequent transfer to Scandinavia followed by retrogression to the NW provides a typical 10-14 day severe spell as we have seen before. 

The risks remain substantial - in splitting or displacing the PV may have enough energy to sink the initial HP into Europe before it goes wandering and the amount of energy in the northern arm of the split jet remains troubling. 

I'm still of the view we are looking at more severe conditions from mid January (halfway through winter for those who are worried or counting) rather than earlier.

[karlos1983]

10 minutes ago, Ali1977 said:

Mmmm, whatever it is that difference in 3/4 days time doesn’t seem right - not buying it.

You’d expect to see a big split further in time not in a few days!! I haven’t seen much else about the signal waining!!  

Yeah I'm inclined to agree with that... Would be very out of the blue..

Edited December 20, 2018 by karlos1983

[snowray]

29 minutes ago, ICE COLD said:

Are old friend @knocker won’t be happy with this chart .

Indeed.

[Ali1977]

12 minutes ago, karlos1983 said:

Yeah I'm inclined to agree with that... Would be very out of the blue..

I’m no strat expert but I think the ECM is much better at strat forecasts, and it’s the GEFS that “slightly” downgraded reverse wind speeds but it’s still a SSW. ECMWF monthlies this evening will hopefully stick with the SSW and add weight to a split vortex , if so, a more positive METO 16-30 day tomorrow maybe

Edited December 20, 2018 by Ali1977

[Daniel*]

7 minutes ago, stodge said:

Afternoon all

Well, the ship has sailed for Christmas cold but the New Year, well, we'll see.

The Parallel has been consistent in splitting the PV on or about 3rd Jan and the GFS 12Z OP looks like ushering s second warming to split the PV soon after 6th Jan.

We'll also see if Amy Butler's tweet is a sign of a backtrack or just some modelling inconsistencies over the next few days.

The substantial pressure rise from the south and the subsequent transfer to Scandinavia followed by retrogression to the NW provides a typical 10-14 day severe spell as we have seen before. 

The risks remain substantial - in splitting or displacing the PV may have enough energy to sink the initial HP into Europe before it goes wandering and the amount of energy in the northern arm of the split jet remains troubling. 

I'm still of the view we are looking at more severe conditions from mid January (halfway through winter for those who are worried or counting) rather than earlier.

White Christmas yes well it never looked realistic, but not surface cold this has firmed up. A ‘white’ Christmas in some sense for many, risk of freezing fog too which will make it feel very wintry much more than norm.  

[Ali1977]

By day 11 I count 10 GEFS perbs following the Op or better - this is a decent upgrade and the chart GEFS ENS chart should be a big upgrade of colder runs after day 12.

edit - not as good as expected but definitely a UK HP on the cards, which would be colder than the 850s depict. 

Edited December 20, 2018 by Ali1977

[karlos1983]

EC monthly will certainly be interesting this evening  

[snowray]

34 minutes ago, karlos1983 said:

Uh oh what’s this about.....

She always seems a bit too negative if you ask me, like todays forecaster saying blah, blah, blah....and ending with "At least it's going to be mild!" Wake up, it's Christmas, thats Winter according to my reckoning, lets get some seasonal weather going....Mild rampers for you!

[shotski]

4 minutes ago, karlos1983 said:

EC monthly will certainly be interesting this evening  

What time does it roll out please ? 

Thanks

[karlos1983]

1 minute ago, shotski said:

What time does it roll out please ? 

Thanks

around 10:30pm i think..

No idea where to view it though, I'll be relying on others in here  

[northwestsnow]

Sounds like there has been quite a shift in the GEFS- !!

[feb1991blizzard]

Just now, karlos1983 said:

around 10:30pm i think..

No idea where to view it though, I'll be relying on others in here  

Here - it starts coming out at 2202 and finishes at 2205.

http://brunnur.vedur.is/kort/ec-ens/2018/

[karlos1983]

Op not without some form of support!

[karlos1983]

3 minutes ago, feb1991blizzard said:

Here - it starts coming out at 2202 and finishes at 2205.

http://brunnur.vedur.is/kort/ec-ens/2018/

That opens a directory Feb?

Do i need to click one of the sub folders?

Edited December 20, 2018 by karlos1983

[The Eagle]

2 minutes ago, karlos1983 said:

Op not without some form of support!

[Penicuikblizzard]

24 minutes ago, snowray said:

Indeed.

That’ll be different by the time the next run is out 

[feb1991blizzard]

Just now, karlos1983 said:

That opens a directory Feb?

then you select the date of the run you want to view, then the time, it will be 0z because its part of the 0z suite not the 12z, then you scroll down to find the first chart you come to that has a 2202 (ish) time stamp on it, and that will be the first chart of the run.

[Johnp]

7 minutes ago, feb1991blizzard said:

Here - it starts coming out at 2202 and finishes at 2205.

http://brunnur.vedur.is/kort/ec-ens/2018/

Can you be a bit more precise?

[feb1991blizzard]

3 minutes ago, Johnp said:

Can you be a bit more precise?

I will tell you later how many seconds after 2202.

[northwestsnow]

wouldn't mind EC following GFS this evening!!

Here it comes, hope we can still at this late stage salvage a seasonal chrimbo

[swfc]

12 minutes ago, northwestsnow said:

Sounds like there has been quite a shift in the GEFS- !!

Can you elaborate nw

[northwestsnow]

Just now, swfc said:

Can you elaborate nw

More members having the high further north