Model Output Discussion - Staying cold into the new year

[Ice Day]

GEFS mean looks great at 144

  

[Daniel*]

I don’t hear much about this but CONUS is forecast to be very mild an aspect which works a lot in our favour. With any blocking not being bowled away by steep thermal gradient.

[AFCBSNOW]

Hi All,

 

I have been lurking in the background for some time.  I have really enjoyed the charts, and different views for both Cold an Mild rampers.  My first question is this.  In regards to the models.............  There seems to be a much varied opinion on here, as opposed to the other site I post on.  My view is we seem to be underestimating home grown cold pooling.  Some of the best charts I have ever seen.  I do wonder though why several members on both here and the other site are writing off something potentially extremely interesting happening, even Post +T144 people are really going crazy.  I say chill and keep the faith.  IMBY its cool nothingness at the moment, but I would rather see the pooling at those Highs doing their thing than the mild zonal dross we have endured in recent years.

Brilliant views, keep it up all.

 

[nick sussex]

The UKMO looks like it’s going to go down the stress route for coldies !

So now we need a stronger ridge over Scandi and any shortwave to remain a shallow feature and not deepen , that needs to move se from near Iceland and phase favourably with low heights to the south .

Looks like a nailed on west based negative NAO on the UKMO , in that case it needs to be as west as possible allowing ridging to the east and ne to keep the UK in the colder conditions .

[tight isobar]

3 minutes ago, Daniel* said:

Seems the UK borders are closed to European cold.

This is a classic brick wall synoptic.. and bears all in the “saying get the cold in 1st “..   we see this via the models often when the signal for cold infer is inevitable.. and I’m glad you’ve highlighted this snap.. as the fruit bearing is raisin rapid.. and I’m sure we’ll see deep encroachment of cold as frames/runs getting nearer within!!!

[Mucka]

GFS P seems to be inline with MetO forecast after Jan 4th

 "There is potential for spells of more organised precipitation, accompanied by stronger winds to move north from the continent into southern and central areas. Additionally, there is also the potential for precipitation to move into northern areas if high pressure declines. Both scenarios could bring an associated snow risk particularly over hills."

[Mike Poole]

GFS // T234:

 

Snowmaker!  

I know the uppersgate debate is still live, but this would deliver! 

[ptow]

Great Synoptics that would undoubtedly bring snow and sub zero maxima if only it were cold on the continent. Sadly though it isn’t and that looks like it will leave us prominently cold and potentially wet

[Ventnor Viking]

The evolution of the 12hr GFS is still looking fine to me. The models will chop and change patterns slightly however its the theme and trend that's more important. There are certain scenarios that the models can't deal with well, one being a messed up strat/SSW. Therefore the models will not handle the coming weeks well in terms of accuracy. So it's important to focus on the evolution i.e. where is the HP heading and where is the cold air shifting etc. Its not guaranteed we will see the perfect set up, but if the trend and general theme remains similar then we are in with a shout heading into mid January. 

[snowice]

To many contradictory posts it's will snow won't snow not cold enough,new members must be right confused.

[Youcan'tbecirrus]

9 minutes ago, Daniel* said:

Seems the UK borders are closed to European cold.

That will be down to brrrexit.

[Met4Cast]

GLOSEA is showing a strong SPV reversal with u-winds not really recovering until the end of January.

Slowly slowly..

 

[SLEETY]

Very odd looking gfs run now,somehow I dont think the reality at that timeframe will look the same lol,but it keeps it cold anyway.

Btw why have the new very knowledgeable posters decided not to post anymore?

[Tim Bland]

Awesome GFSp with snow opportunities galore. I get the nervousness when one or two models go wrong but I think we are just spoilt these days with too many models to view. It’s a bit like looking at all the ensembles from a. Model and focusing on the bad ones. If each model was an ensemble - We would be saying that the icon is a mild outlier and the GFS is at the top of the pack and unlikely ...

[Anti-Mild]

2 minutes ago, snowice said:

To many contradictory posts it's will snow won't snow not cold enough,new members must be right confused.

Haha, i've been a member since 2002 and i'm confused! A lot of it seems to be rooted more in psychology than in meteorology - glass half full vs. glass half empty and all that.

[phil nw.]

26 minutes ago, Mike Poole said:

GFS just now T180 getting near to where the UKMO was at T144:

The reason - too many shortwaves and complicating features on GFS, one complicating feature still remains, circled.  The main driver seems the same - towards a Greenland plus high, by which I mean heights extend further north (I mean north on a Meteociel chart not true north!) than Greenland, we’ve seen it on a number of runs lately, but the models have different ways of getting there.  

Yes Mike i noticed yesterday GFS was 2 days behind with the move towards Greenland.I am happy with both up to day 5.Getting colder as early as t72 with -8c uppers heading south and then the easterly with similar readings from the weekend.

The flow from the ne just cooling things more with time as it connects with the cold pool over N.Russia.These set ups often model colder nearer the time.

[Griff]

3 minutes ago, Met4Cast said:

GLOSEA is showing a strong SPV reversal with u-winds not really recovering until the end of January.

Slowly slowly..

 

Resembles Monday night's ecm...

[bluearmy]

13 minutes ago, Frosty Winter said:

UKMO, GFS(p) and GEM all in fairly good agreement at t144. GFS is the odd one out now.

If we leave gfs behind then we may just have some cross model agreement on the trough dropping around day 8/9. cue ecm op to back this up ! 

[Lukesluckybunch]

I have to say looking at the latest gfs run,it's so frustrating to see that all the cold air filters down the east of us into Mainland europe.it happens every winter really

[Mucka]

With the models serving up synoptic stew forecasting for England beyond a few days is going to be very difficult beyond offering inexplicit phrases such as, "remaining on the cold side with rain, sleet and snow at times."

[The PIT]

2 minutes ago, Lukesluckybunch said:

I have to say looking at the latest gfs run,it's so frustrating to see that all the cold air filters down the east of us into Mainland europe.it happens every winter really

Lala land so don't lose sleep over it. Tomorrow it could show a mega beast from the east at the same time period.

[Mike Poole]

1 minute ago, Lukesluckybunch said:

I have to say looking at the latest gfs run,it's so frustrating to see that all the cold air filters down the east of us into Mainland europe.it happens every winter really

Ignore the GFS this 12z run, it has gone wrong!  The other models paint a very different picture, and I’m sure the ECM will back this up in an hour or so!  

[sukayuonsensnow]

Looking at the overall models, I would be surprised at this point if most of southern UK has a notable snowfall (7cm accumulation or more) in the next couple weeks. There's still potential but this cold spell is more for northern England, Central and Northern Wales and Scotland.

There's still matters to be determined with how cold the air is over the UK next week, and that will determine what falls out of the sky for many.

[Frosty.]

For sure, the Gfs 12z op looks cold well intooo the new year..hoorah!!..and for sure there would be some snow in the forecast next week judging by the precipitation charts?...I’m still thinking wintry reloads from the north / east further ahead with high pressure generally to the west / north?...enjoy the ride!

Edited December 30, 2020 by Jon Snow

[Mucka]

2 minutes ago, bluearmy said:

If we leave gfs behind then we may just have some cross model agreement on the trough dropping around day 8/9. cue ecm op to back this up ! 

 

We may, but we also have the trough pushing N at the same time which means even if we get that basic pattern nailed there is likely to be very different scenarios of how that happens and what it means for Britain followed by even larger divergence thereafter than the norm.

Great for model watching but a nightmare for forecasting.