Model Output Discussion - Into Winter

[northwestsnow]

Day 8 EC

We look west ..

[Silberhorn]

6 minutes ago, northwestsnow said:

Day 8 EC

We look west ..

 As in “the HP is heading West”?

[Northwest NI]

27 minutes ago, lewis clark said:

The snow and cold arrives on the 22nd at 6pm according to gb news lol!

I made it quarter past 6. Damn another fail for me!

[booferking]

Old Scrooge is a slow burner.

[northwestsnow]

3 minutes ago, booferking said:

Old Scrooge is a slow burner.

Need that vortex to do one !!

[Midlands Ice Age]

and now for the December of 1962-3

1 hour ago, Midlands Ice Age said:

Reports on the NOAA NCEP Reanalysis show that about the 15 - 16th of December 1961 high pressure moved up from the south, and it stuck around just to the west of Northern Ireland for about 5 days . During this time it kept trying to ridge to the NW towards Greenland, but it never made it beyond Iceland, and eventually towards the 20th it settled towards the East of the Northern Isles.  Here it hung on for a couple of days before  the blast of the colder air to the north pushed it a bit further west.  There was no Greenland high until later on in the run.

During this time the weather over the UK was cold with extensive fog and the temperature gradually fell so Xmas was cold, and frosty with night time lows dropped from -4C to -10C . It was Boxing day onwards that a low from the Atlantic went under, up the Channel,  and the rest was history.

I remember it well....

See the reanalysis of it all in the link below -

1961 December

MIA

and now for the real daddy of a winter 1962-3.......

Started off in a very similar way, with a high pressure developing from the south. This time it was a bit further west and ridged up strongly towards the north east initially before the pool of cold air swept around the eastern flank, and induced  a low pressure to our south. This pushed the anticyclone back towards Iceland. 

The high pressure then proceeded to seal off the Atlantic for a considerable spell.

Could it happen again... probably not. The atmosphere was clearly in a state to enable burgeoning high pressure.

MIA

December 1962

Edited December 8, 2023 by Midlands Ice Age

[northwestsnow]

Day 10 - 

[SqueakheartLW]

For those of us like me who have really missed the GFS extended run after it had played up for what seemed like an eternity can be pleased now it appears to be back up and running once again

I always liked looking at the runs post +384h just for fun and to see what crazy or unrealistic scenarios it was churning out.

Just for fun here's the coldest or potential cold or snowy Christmas Day charts

Cold and possibly wintry

P01

P05

P07

P12

P14

P25

Battleground / Southerly Tracking Low options

P03

 

A good few there to look at. Note P02, P04, P08, P10, P16, P17, P18, P21 (Worst one), P22 and P24 are horror show Christmas Day charts for coldies all with 850hpa temps widespread over the UK above 0C. P21 as indicated is the worst with +5C isotherm widespread over the UK. I don't recommend you view these unless as a coldies you want to throw up.

[joggs]

23 minutes ago, northwestsnow said:

Day 10 - 

If the background signals carry on the way they are,I can see the PV draining away from Greenland. I'm quite happy with that.

[Bricriu]

Well it looks  nailed on to be dry  looking at the lastest output for after mid month. After three days of non stop rain and gloom,  I am  looking forward to some dry weather again. Cold and snow would be a bonus. Hopefully the UKMO and ECM will follow the GFS in future runs, but as a poster said cold rarely comes in sooner than anticipated,  so it could be see a colder turn the far side of Christmas. At least we are in the game for  a white Christmas.  It must be 19 years since I last had one. Come on 2023 deliver one!

[WYorksWeather]

Much interest of course in how things look in the run up to Christmas, but first I'd like to take a look at UKV. As I've been saying for the past few days, some very mild conditions over the weekend, and this does seem to be materialising. Looks like a high of 12C has been recorded today. Looking ahead, based on today's UKV 15z, here's where we're going.

UKV 03z minima from Saturday - Wednesday. Looks like a very mild three nights to come, then very gradual signs of a change as we move towards the middle of a change. By Wednesday milder air still hanging on further south, with northern and central England somewhere in the middle and Scotland seeing widespread frosts.

 

UKV 15z maxima from Saturday - Wednesday. Similar theme. The daytime maxima for Saturday-Monday have reduced somewhat compared to forecasts from a few days ago, but still will see means near 10C in the south. Signs of a change by Wednesday as a UK high starts to set up, with a more seasonal feel with cooler days and nights.

Might do another sea surface temperature look later, but I'll leave it at that for now. I prefer not to speculate about Christmas at this range as we've been led up the garden path far too many times.

[BLAST FROM THE PAST]

Have a look at the GFS control 12z.  Basically at various stages 21-24 Dec the whole GB and Ireland will likely see snow….

NW and West get it.

 

Then NE/E/SE get it.  

but tbf that looks fairly widespread.  

BFTP

Edited December 8, 2023 by BLAST FROM THE PAST

[northwestsnow]

7 minutes ago, BLAST FROM THE PAST said:

Have a look at the GFS control 12z.  Basically at various stages 21-24 Dec the whole GB and Ireland will likely see snow….

NW and West get it.

 

Then NE/E/SE get it.  

but tbf that looks fairly widespread.  

BFTP

That's just  

[BLAST FROM THE PAST]

2 minutes ago, northwestsnow said:

That's just  

For you….amazing

 

 

BFTP 

[LRD]

EC46 

Week of 18th Dec

Christmas week

Slight relaxation week of 1st Jan but then... 8th Jan

Edited December 8, 2023 by LRD

[pinball wizard]

4 hours ago, northwestsnow said:

I think that's fair comment.

I was hoping they might ref the chance of colder conditions by the 22nd but perhaps the second update will be more revealing ..

The Met would know that with low probabilities there is NO point in feeding a pre-christmas WALL OF SNOW media frenzy. And rightly so.

Their job is to provide reasoned forecasts not speculate as to longer term, we can do the latter here for them

[northwestsnow]

EC maintains the general theme of the anticyclone being dragged west around Christmas.

Looks quite a drawn out affair but the model maintains consistency..

[booferking]

Ec control about offload the Arctic to our shores in time for Christmas.

[Daniel*]

The period of interest is still out ECM op range, so I wouldn’t feel concerned right now. I also have a sneaky suspicion it’s not yet quite capturing MJO passage that well we have been here before with ECMWF. 

[TillyS]

Mild outlook at present. Nothing is nailed on for 7 days from now though. The position of the apparent high pressure cell is all-important. If it sits to the south as per the European models then it certainly won’t be dry in the north-west of the UK. That would be a very mild, even warm, moist sub-tropical feed.

GFS recent scenarios of the high being further north, even retrograding westwards, may be correct but has no current support from ECM or UKMO.

Nothing nailed on from T168 onwards at the moment but if you’re seeking cold scenarios out of this you’ll probably be able to find them. 

 

[Met4Cast]

2 minutes ago, TillyS said:

Mild outlook at present. Nothing is nailed on for 7 days from now though. The position of the apparent high pressure cell is all-important. If it sits to the south as per the European models then it certainly won’t be dry in the north-west of the UK. That would be a very mild, even warm, moist sub-tropical feed.

GFS recent scenarios of the high being further north, even retrograding westwards, may be correct but has no current support from ECM or UKMO.

Nothing nailed on from T168 onwards at the moment but if you’re seeking cold scenarios out of this you’ll probably be able to find them. 

 

The ECM & UKMO wouldn’t be able to support the GFS because they don’t cover the period of interest.. 

There is however support for the GFS amongst the extended EPS. 

[booferking]

Just now, TillyS said:

Mild outlook at present. Nothing is nailed on for 7 days from now though. The position of the apparent high pressure cell is all-important. If it sits to the south as per the European models then it certainly won’t be dry in the north-west of the UK. That would be a very mild, even warm, moist sub-tropical feed.

GFS recent scenarios of the high being further north, even retrograding westwards, may be correct but has no current support from ECM or UKMO.

Nothing nailed on from T168 onwards at the moment but if you’re seeking cold scenarios out of this you’ll probably be able to find them. 

 

Yes it does the EC control is the op extended and there are many geps in support also.

Compare both charts remarkably similar that far out steady as she goes.

[WYorksWeather]

 

The cold signal does not arrive until around the 21st, and even at that point, it's only a little below average. The scatter is also enormous. I think it's best not to get ahead of ourselves regarding Christmas run up. We're in a good position for something a bit more seasonal around the middle of next week with a UK high - let's see how that works out and then take it from there.

You will nearly always be able to find cold ensemble members, and an odd OP run from time to time, since we have ten or more runs per day from the major models combined.

I will be watching these charts with interest. Once we see the mean line starting to break below average, and particularly if it starts to break below -5C, within the at least semi-reliable timeframe (7-10 days), I'll start to take a look at it more closely.

[alexisj9]

2 hours ago, lewis clark said:

The snow and cold arrives on the 22nd at 6pm according to gb news lol!

Enogh to keep me well away from the channel, no matter what the discussion, if they sensationalise weather, they'll do that with everything else as well.

[AdrianHull]

3 minutes ago, alexisj9 said:

Enogh to keep me well away from the channel, no matter what the discussion, if they sensationalise weather, they'll do that with everything else as well.

They even have the exact time the Nordic snow wall hits too! 6pm on the 22nd 

Edited December 8, 2023 by AdrianHull