Model output discussion - Christmas approaches

[Battleground Snow]

Ec46, wow! High risk high rewards for week 2

Edited December 16, 2021 by Battleground Snow

[LRD]

1 minute ago, Mike Poole said:

Having watched the models chase this setup over the last few days, I’m not on board with the idea that suddenly from 0z to 12z, this high is going so far north it gets into orbit!  (Yes I know that is not possible , it’s a metaphor).  For once I will welcome the 0z runs with their more conservative zonal bias!

And to back that up here is the week of 20-27 Dec on the latest EC46:

The rest of the run looks decent too

[ICE COLD]

You can see it on the MOGREPS graph if it pushes to far north temps rise but to be fair there’s still loads that keep temps down =keeps it further south . Still all to play for . 

[SqueakheartLW]

Just using GFS 12z 850hpa temp charts for my examples shows how much uncertainty there is for a potential snow event next Thursday 23rd.

I roughly picked out 4 groups within the big majority of the ensembles that show a battleground of some sort

1 - The approximately Midlands battleground (Op, P12, P19, P24, P25, P26 and P29)     7 of 31 options

This first group for me personally is the one I hope comes off as it has the maximum snow chances for my part of the country although others on here may want to pick one of the other groups for their best chances.

2 - The Scotland / Far N of England Battleground (Ct, P03, P05, P13, P16, P17, P18, P21 and P27)     9 of 31 options

The largest cluster of the ensembles currently has the battleground further north around Northern England or Scotland but as these events have a tendency to correct southwards come the day then this gives hope that the Midlands is in the firing line when the time comes.

3 - The Southern Battleground (P07, P10, P23 and P30)     4 of 31 options

You could almost call this the rare "south of M4 event". Now we know how rare these snow events are south of the M4 but if this cluster comes off then it will very likely end up a "south of the M4 event" and this would please a few coldies who live right down there. Couldn't correct any further south or we would all miss out entirely.

4 - Too Far North Battleground (P11, P22 and P28)     3 of 31 options

These are very much the horror show options where the boundary between mild and cold is so far north that basically only Shetland has any chance of any snow here and this is a push too with some of these charts. Now we would definitely want corrections south here.

The other 8 ensemble members

The remaining 8 ensemble members were very much not applicable to the potential battleground situation. They were either mild with westerlies dominating or were under mild or cold uppers with high pressure stuck right over the UK.

[LRD]

The 500 hPa charts are even more impressive. 20th-27th

27th-3rd Jan

I think Battleground Snow has beaten me to it!

[swfc]

2 minutes ago, LRD said:

And to back that up here is the week of 20-27 Dec on the latest EC46:

The rest of the run looks decent too

They are decent. One is much further north and one over the UK. That said subject to change esp over the UK ie cold and warm boudries ie blue army's Post.

[knocker]

Still a lot of uncertainty regarding the detail through the end next week and over the Xmas weekend. Although the very cold vortex air is likely to descend over eastern Europe, temps over the rest of Europe, including the UK, are still likely to be below average. This is complicated by the other energy flow south of the Greenland block pushing troughs towards the UK from the west. All resulting in a number of possibilities

[Beanz]

8 minutes ago, Mike Poole said:

Having watched the models chase this setup over the last few days, I’m not on board with the idea that suddenly from 0z to 12z, this high is going so far north it gets into orbit!  (Yes I know that is not possible , it’s a metaphor).  For once I will welcome the 0z runs with their more conservative zonal bias!

I was thinking this myself, I’m not satisfied we’re any the wiser for what’s in store come next Friday 

[GSP]

I find this chart quite funny in a way. We know it will change, but the potential that is there if the air was a bit colder and with all instability in the atmosphere. Those who want us to have minimal contact over Christmas might just get their way if this trend continues, we won’t be able to venture too far!

 

[bluearmy]

A little surprised at the fanfare for the ec 46 out to jan 3rd

we already knew what these would look like from the normal 00z eps mean this morning 

it’s the period behind 3 jan which is where we’re looking for clues and the run maintains the blocking signal although not as impressive as Tuesday - looks like it’s unsure where to place the upper ridge /wedge 

[northwestsnow]

EC 46 is tremendous.

Northern blocking and Euro low = happy campers.

[Lukesluckybunch]

Just now, northwestsnow said:

EC 46 is tremendous.

Northern blocking and Euro low = happy campers.

is it really that good? what did you think of the ECM northwest...

[knocker]

6 minutes ago, bluearmy said:

A little surprised at the fanfare for the ec 46 out to jan 3rd

we already knew what these would look like from the normal 00z eps mean this morning 

it’s the period behind 3 jan which is where we’re looking for clues and the run maintains the blocking signal although not as impressive as Tuesday - looks like it’s unsure where to place the upper ridge /wedge 

I am equally puzzled

[northwestsnow]

Just now, Lukesluckybunch said:

is it really that good? what did you think of the ECM northwest...

EC is good -

Next 48 hours critical for snowline ..

[Cheshire Freeze]

Anyone N of about Brum should be very happy with that ECM run at face value. Just a barrage of systems into cold air.

[Radiating Dendrite]

3 minutes ago, northwestsnow said:

EC is good -

Next 48 hours critical for snowline ..

Think you need to add an extra 100 hours onto that! Snow line can be a few miles. 

[LRD]

10 minutes ago, bluearmy said:

A little surprised at the fanfare for the ec 46 out to jan 3rd

we already knew what these would look like from the normal 00z eps mean this morning 

it’s the period behind 3 jan which is where we’re looking for clues and the run maintains the blocking signal although not as impressive as Tuesday - looks like it’s unsure where to place the upper ridge /wedge 

Just trying to address the point/concern that some had expressed about the clusters and op going too far north and north west with the High. Thought I was being helpful! 

[Battleground Snow]

2 minutes ago, LRD said:

Just trying to address the point/concern that some had expressed about the clusters and op going too far north and north west with the High. Thought I was being helpful! 

And it also maintains blocking well into January, specifics are not going to show past 3 weeks, the alignment will be up for grabs

 

[northwestsnow]

1 minute ago, Radiating Dendrite said:

Think you need to add an extra 100 hours onto that! Snow line can be a few miles. 

Yes , but we should have a much better idea this time Saturday..

 

 

[LRD]

Just now, Battleground Snow said:

And it also maintains blocking well into January, specifics are not going to show past 3 weeks, the alignment will be up for grabs

 

Agreed - the signal is inevitably going to weaken the further in time we go but EC46 looked ok going into next month too

[chris55]

33 minutes ago, Battleground Snow said:

Ec46, wow! High risk high rewards for week 2

Cotswolds/South Wales/ Bristol to get pasted with snow in these set ups ……

I’ll get my coat…..

(winter coat and the sledge )

 

[Daniel*]

Definitely a shift in wrong direction before and after Xmas. Hopefully we see better in morning.

00z EPS

12z

 

If it fails could be a wet spell for south 

 

 

[geordiekev]

1 hour ago, Ali1977 said:

1/12

Odd as it used to be nearer 12/1 as that was the statistical probability. When was our last Not far off

[BlueHedgehog074]

8 minutes ago, CreweCold said:

Anyone N of about Brum should be very happy with that ECM run at face value. Just a barrage of systems into cold air.

Indeed Crewe. Around here, and further South on that run, you may very well need a boat

Was really hoping to try not get distracted to the models this Winter. But when they throw out scenarios like this, MOA (Model Output Addiction) pounces on you like a cat.

Hopefully, with this setup (unless cold and snow is something you don’t want), none of us will be needing the boats!

[LRD]

7 minutes ago, Daniel* said:

Definitely a shift in wrong direction before and after Xmas. Hopefully we see better in morning.

00z EPS

12z

 

If it fails could be a wet spell for south 

 

 

Yep fair point. I think we're just going to have to put up with a lot of inconsistency on the detail. Some of those charts might be very good (for cold) over the coming days and some will be less good. Unless things continue to trend north of course!