Model Output Discussion - Into 2024

[Daniel*]

Absurd difference at day 5 between UKMO & GFS, if we thought 00z was going to give a clear answer we would be mistaken. Both are consistent one is consistently wrong.

Edited January 10 by Daniel*

[WolfeEire]

23 minutes ago, stewfox said:

GFS oz rolling out now 

At 114 hrs 0z first and 18z second 

 

 

 

 

 

Another GFS op run which looks like it will probably be a mix of the good, the bad and the ugly.  Good entertainment but better off waiting for the GEFS. 

Edited January 10 by WolfeEire

[Kasim Awan]

A definite trend towards the GFS this morning with the UKMO, ICON and GEM now all introducing a warmer sector behind the initial northerly around 16th of January. This is not a "cold spell is over" type post - just an indication that the cold spell will likely have a warmer sector during this period. It also raises some concern for warmer sectors going forwards as this setup reduces WAA into Greenland significantly. 

[Lukesluckybunch]

Ukmo is nicegfs seems good aswell..the timing looks to be perfect,with the trough dropping down..and heights fading over iberia

[Cheshire Freeze]

2 minutes ago, Kasim Awan said:

A definite trend towards the GFS this morning with the UKMO, ICON and GEM now all introducing a warmer sector behind the initial northerly around 16th of January. This is not a "cold spell is over" type post - just an indication that the cold spell will likely have a warmer sector during this period. It also raises some concern for warmer sectors going forwards as this setup reduces WAA into Greenland significantly. 

You were correct about those Iberian heights. They’re preventing that Atlantic LP from sliding across France.

[Battleground Snow]

2 minutes ago, Kasim Awan said:

A definite trend towards the GFS this morning with the UKMO, ICON and GEM now all introducing a warmer sector behind the initial northerly around 16th of January. This is not a "cold spell is over" type post - just an indication that the cold spell will likely have a warmer sector during this period. It also raises some concern for warmer sectors going forwards as this setup reduces WAA into Greenland significantly. 

Agreed, looks like we are relying on residual heights south of Greenland to send that jet south now 

Still could be a snowy outcome further down the line.

Ukmo moved a little to the gfs, but gfs has also moved the other way a little too.

[Kasim Awan]

Just now, Battleground Snow said:

Agreed, looks like we are relying on residual heights south of Greenland to send that jet south now 

Still could be a snowy outcome further down the line.

Ukmo moved a little to the gfs, but gfs has also moved the other way a little too.

Yes but the UKMO has moved to the GFS more than the contrary. So we need to be realistic and factor in potential significant warm sectors here. There is still a real risk of heavy snowfall. 

[Daniel*]

GFS better than previous run better ridging into Greenland the 18z collapsed blocking very quickly and more sharper dig to cold trough into N UK the deep Scandi trough being quite influential there. 

Edited January 10 by Daniel*

[Lukesluckybunch]

Gem

[Battleground Snow]

Just now, Daniel* said:

GFS better than previous run better ridging into Greenland the 18z collapsed blocking very quickly and more sharper dig to cold trough into N UK the deep Scandi trough being quite influential there. 

Gem is holding on better in Greenland, I imagine this run will get snowy later on too 

[joggs]

1 minute ago, Battleground Snow said:

Gem is holding on better in Greenland, I imagine this run will get snowy later on too 

Them beautiful ne ............over Iceland

[Penguin16]

Certainly doesn’t look like a screaming unstable northerly is on the cards. Looks pretty dry further west, eastern areas exposed to a northerly look best placed for snow showers after northern Scotland. Pretty underwhelming overall compared to a few days ago for late weekend/early next week on current guidance.

[Kasim Awan]

Output has improved for 168h-210h however the 120h-168h has once again downgraded, I'm not a fan of these pesky medium term downgrades. 

However there is still a very decent chance of a significant cold spell.

[stewfox]

Sub -10c coming into Scotland sooner on 0z then 18z at T180

[Battleground Snow]

3 minutes ago, Kasim Awan said:

Output has improved for 168h-210h however the 120h-168h has once again downgraded, I'm not a fan of these pesky medium term downgrades. 

However there is still a very decent chance of a significant cold spell.

I think that's a fair assessment this morning,

Perhaps ukmo and ecm might be a little better, at 168, but the situation remains very fluid  over Greenland 

People won't like the short delay, but the overall pattern hasn't changed drastically 

Edited January 10 by Battleground Snow

[Lukesluckybunch]

Lovley stay on the cold side gfs...gem where's that cold air going at day 9...erm nowhere!

[Lukesluckybunch]

Gfs going mad with snow late next week in the South..what do you want 10/20cm!?

[Kasim Awan]

Just now, Lukesluckybunch said:

Gfs going mad with snow late next week in the South..what do you want 10/20cm!?

I think we need to wait until this next chance of a very cold north easterly comes into the 168h time frame as there is a real risk it will be downgraded as the models correctly model the strength of the Iberian high within a more reliable time frame.

Nevertheless the general outlook is cold and wintry.

[Daniel*]

Models haven’t exactly pushed the cold back, even if it’s not pretty… cold air in place by 15th on GFS & UKMO. Clearly models will struggle resolving how this is thrown about. 

Edited January 10 by Daniel*

[Battleground Snow]

3 minutes ago, Lukesluckybunch said:

Lovley stay on the cold side gfs...gem where's that cold air going at day 9...erm nowhere!

Yep by day 8/9, both gem and gfs are snowy runs

[Battleground Snow]

3 minutes ago, Daniel* said:

Models haven’t exactly pushed the cold back, even if it’s not pretty… cold air in place by 15th on GFS & UKMO. Clearly models will struggle resolving how this thrown about. 

Yeh certainly no complaints from me,

Good runs this morning, good to see the back of those gfs runs from yesterday too

Edited January 10 by Battleground Snow

[Lukesluckybunch]

2 minutes ago, Kasim Awan said:

I think we need to wait until this next chance of a very cold north easterly comes into the 168h time frame as there is a real risk it will be downgraded as the models correctly model the strength of the Iberian high within a more reliable time frame.

Nevertheless the general outlook is cold and wintry.

I agree kasim cold and wintry looks very likely..all about the timing..shortwaves etc.causing a lot of confusion

[Kasim Awan]

Just now, Lukesluckybunch said:

I agree kasim cold and wintry looks very likely..all about the timing..shortwaves etc.causing a lot of confusion

The potential is there for a bout of significant, heavy snow events 16th-19th before development of a cold inversion towards 18th/22nd. 

This is probably the most likely outcome at this point. 

However, we need to be steady as the phasing to our south west looks slightly less optimal than it did a few days ago, and so it wouldn't take much to scupper the cold flow entirely at this point.

[Ben Sainsbury]

Relatively speaking, a pretty good set of runs so far this morning. GFS and GEM producing a fair amount of snow mid-run, UKMO likely to do the same. Closer to the present, not particularly cold but remaining settled which is nice (imo). As mentioned before, still pretty large differences even at T120. 

[Daniel*]

GFS is a throwback to some of those 1980s winters an active but cold pattern targeting central and southern parts. Very intrigued about next week and potential for high impact winter weather.

Edited January 10 by Daniel*