Model Output Discussion - Christmas and New Year

[Mike Poole]

40 minutes ago, Griff said:

Humour me, I've heard, almost secondhand, chatter this week about the duration of a reversal... Is this a known quantity or unique every time etc? I'm aware that outcomes are like rolling the dice. 

A SSW, when it happens is quick, but what happens after can  be slower.  And how long it lasts for is also uncertain. And which part of the mid-latitudes it affects is also uncertain.  The 2018 SSW had a fast tropospheric response, just as well because we were out of winter and running on fumes by that point!  The 2019 one did nothing for us at all. 

This one, the 2021 SSW, is likely (in my opinion) to lead to a split with a quick tropospheric response, given the trop vortex is already marmalized,  reinforcing, possibly quite significantly, patterns that are there now already, for our region, i.e. the cold ones shown on the ECM and GFS right now, with high latitude blocking and height rises around Greenland heading to Scandi as well later.  This is by no means certain, and  a couple of weeks go it was more uncertain, but it is what I think now. 

We will see...onto the pub run...

 

Edited December 24, 2020 by Mike Poole

[Allseasons-Si]

Pressure over the S tip of Greenland 

ECM and gefs.

Edited December 24, 2020 by Allseasons-si
Missed capital letter

[Eagle Eye]

MERRY CHRISTMAS Everyone ghe Charts have been showing many A Toppler, Arctic Northernlies and Azores High's but on the 8th Day Of Christmas My True Love Gave To Me : 8 Arctic Northernly's (One IS Enough Imagine Though)

 

 

[Nick1972]

Been lurking in the background for many years but have learnt so much from the more experienced knowledgeable folk on this excellent forum. Now time to watch Day after tomorrow and enjoy our own cold spell however it develops Merry Christmas to you all ❄

[Mike Poole]

ICON rolling, and this is some weather system (on any model) T84:

The lack of isobars in the core of it is baffling to me, but ECM has showed it too.  I think while this feature passes, virtually anything could happen virtually anywhere?  

[sheikhy]

1 minute ago, Mike Poole said:

ICON rolling, and this is some weather system (on any model) T84:

The lack of isobars in the core of it is baffling to me, but ECM has showed it too.  I think while this feature passes, virtually anything could happen virtually anywhere?  

I mean the thicknesses are just something else!!you normally see thickneesess and purples like that in the north pole!!!cold air gets trapped in the heart of that as well

[BARRY]

2 minutes ago, sheikhy said:

I mean the thicknesses are just something else!!you normally see thickneesess and purples like that in the north pole!!!cold air gets trapped in the heart of that as well

And that is in the good timeframe 

 

[Allseasons-Si]

8 minutes ago, Mike Poole said:

ICON rolling, and this is some weather system (on any model) T84:

The lack of isobars in the core of it is baffling to me, but ECM has showed it too.  I think while this feature passes, virtually anything could happen virtually anywhere?  

I was looking at the earlier timeframes,what a monster weather bomb that is at 955mb.

i mean,...it's like a "day after tomorrow" system ha!ha!

 

Edited December 24, 2020 by Allseasons-si

[Griff]

1 minute ago, Allseasons-si said:

I was looking at the earlier timeframes,what a monster weather bomb that is at 955mb.

All very zonal

Is joke, innit? 

[alexisj9]

7 minutes ago, Mike Poole said:

ICON rolling, and this is some weather system (on any model) T84:

The lack of isobars in the core of it is baffling to me, but ECM has showed it too.  I think while this feature passes, virtually anything could happen virtually anywhere?  

Yep that's Bella in all her glory. Gonna get very windy down here.

[georgiedre]

22 minutes ago, Allseasons-si said:

Pressure over the S tip of Greenland 

ECM and gefs.

How can I get the Iceland ones

[Decemberof2010]

Merry Christmas everyone.

10 years ago we had a month we will never forget. It was enough to make me join this fantastic forum a few years later, as I became more interested in how the weather is forecasted using models and other data. I've always been a lover of cold and snow and have experienced a fair few notable spells here in Yorkshire.

Could we now be on the verge of seeing charts like the following popping up a decade later?

We are massively in the game guys and gals.

Here are a few from December of 2010

 

 

 

[cyclonic happiness]

Some of the best winter snowfalls we've ever had, have been from much more marginal situations....850s of -1'c and dew points of -1.4'c , or so. The next weeks could be amazing. I'd rather live in a daydream of Narnia , it's as near as we got last winter

Edited December 24, 2020 by cyclonic happiness

[Allseasons-Si]

Height's more into Greenland on the latest ICON thanks to a little more downstream trough NE states.

18z 120 v's 12z 126

[chris55]

It’s Christmas Eve and the models are filled like a stocking.

We are excited, but not quite sure what the big man is offering.

It’s full of potential for sure.

But will the snow fall.

Watch the sky’s and be awed, or look at the puddles and be floored.

Regardless, Net weather at Christmas is simply adored. 
 

MERRY CHRISTMAS YOU FILTHY ANIMALS X

‍

[Mike Poole]

3 minutes ago, cyclonic happiness said:

Some of the best winter snowfalls we've ever had, have been from much more marginal situations....850s of -1'c and dew points of -1.4'c , or so. The next weeks could be amazing. I'd rather live in a daydream of Narnia , it's as near as we got last winter

Yes!  The best snowfalls often come from marginal situations, and looking at the models that is what we will have from Sunday into Monday, but also a very disturbed weather system.  I can’t imagine what will happen yet - hopefully the high res models might help in the next day or two, but this really could come down to nowcasting.   

[Scott Ingham]

Might be nothing and as it stands the showers look very light but i have noticed showers being shown behind the main rain band saturday night turning to snow sunday monday in the cheshire gap. 

Its things like this that can turn up short notice. 

Get the cold in then always keep an eye on the charts within 48hours

[Mucka]

1 hour ago, Steve Murr said:

ECM is going to be a big mild outlier for the UK V the EPS mean. Excellent mean all the way through.

ECM keeps blowing up systems SW of Greenland.

Look at the OP 3 days ago for 31st now tonight for the 31st

 

Yes for some reason GFS seems to model Shortwaves and lows around SW tip of Greenland better and that includes when it finds spoiler Shortwave/lows not modelled by the Euros so fingers crossed ECM isn't leading on that.

Edited December 24, 2020 by Mucka

[mulzy]

Merry Xmas one and all.

Let’s drink to a cold and snowy outlook!

[Daniel*]

If you like mild weather look away!

Merry Christmas all, this is a fab site... a great mix of abilities but always a joy most of the time.

[Allseasons-Si]

Well it's the last run before Christmas coming up and i would like to thank everyone on NW for there friendship and knowledge that you have brought to this nice friendly forum so cheers everyone and i hope that this winter will deliver the white goods to us all

                                                                                   

right,come on pun run,give us a Narnia special

 

Edited December 24, 2020 by Allseasons-si

[BARRY]

Just now, mulzy said:

Merry Xmas one and all.

Let’s drink to a cold and snowy outlook!

It's gonna be one hell of a ride Merry Christmas to you all.

[Steady Easterly]

Good Evening, some eye watering synoptics on offer lately, the best model watching in many a good year, so reminiscent of the classic winters of the late seventies/early eighties with repeated bouts of northern blocking with southerly tracking lows,dont worry about uppers as its early days after a long mild period,  and ive already got a covering of snow out my window freezing hard under clear skies, the deep cold will come, i think we are eventually heading for a north easterly turning easterly--rinse repeat, exciting times, cherish them, they are rare. Merry Christmas.

[Griff]

Just getting this in first but anything dislikeable over the next couple of days in the models is definitely down to lack of weather balloons and fewer aircraft, after all, this is the first ever Christmas!

Anything good, that's banked, and data collection is fine... Got it? 

[Mike Poole]

10 minutes ago, Griff said:

Just getting this in first but anything dislikeable over the next couple of days in the models is definitely down to lack of weather balloons and fewer aircraft, after all, this is the first ever Christmas!

Anything good, that's banked, and data collection is fine... Got it? 

No, data from aircraft has been missing since march, doubt Christmas will make any further difference! But it is something we have to discuss every year, or it wouldn’t be the netweather i know nice though, reminders of happier times.

Edited December 24, 2020 by Mike Poole