Model output discussion - deep cold inbound?

[Ice Day]

Sunday daytime highs!!!!

[DJ Fart]

I can't believe how stressful this still is at such a short time frame! It doesn't seem like five minutes ago when it was Monday night and people were saying "we should know by tomorrow"...then Tuesday night...then Wednesday night...then the GFS decides to play a little joke on us...looks great again now and the cheeky little scamp gets a hair ruffle, rather than a slap! 

[Griff]

Just now, Battleground Snow said:

No para tonight.

"NOAA GFS parallel
Another problem to download files on"

 

In which case the op better be on form  

 

[IDO]

Lovely clean easterly flow Sunday to Monday, so showers should push through to the west:

Streamer potential! Much better run on the 18z for the short-term and moving towards the other models so hopefully no more dramas up to Tuesday?

[seabreeze86]

Very small differences make all the difference. Very subtle upgrades slight drop of heights peps up the Convection. The North Sea snow machine is full flow from this chart

[CentralSouthernSnow]

1 minute ago, IDO said:

Lovely clean easterly flow Sunday to Monday, so showers should push through to the west:

Streamer potential! Much better run on the 18z for the short-term and moving towards the other models so hopefully no more dramas up to Tuesday?

Channel streamer? 

[Kasim Awan]

The GFS 18Z is good for a few reasons

> Improved cold air in the SE > better snow ratios (1:10 at 0C but 1:15 at -1C). Wind speeds @ 15-20mph lead to high snow drift index (research topic), especially inland at altitude where theoretically 2-3ft drifts would ensue a la Chilterns, Cambridgeshire on 18z say late Sunday

> Lower height core over North Sea is well defined (if anything more than 12z), leading to optimal streamer activity in the East, North East, convective parameters not quite as good as 2010 nor 2018. BUT to make up for it the loss in height volatility INCREASES longevity of streamers, producing 10-20cm widely so totals at close of play are not far off if not similar

 

Bring it on

 

[TEITS]

We should all sit back and forget about snowfall, breakdown of cold spell and marvel at the N Hemisphere chart at only +48. I have lost count how many times I have drooled at +384 charts but even those didn't match what we are seeing at +48.

[Cloud 10]

2 minutes ago, Ice Day said:

Sunday daytime highs!!!!

 

That will be +4c on BBC graphics.

[ancientsolar]

is it just me or is our "concerning low" becoming slightly weaker in comparison to former runs?
 
 

[Scott Ingham]

51 minutes ago, AppleUK 123 said:

I really wouldn't worry about that, from what I've read on this thread the ICON is not good at forecasting convection so if anything this probably an underestimate of precip. 

The icon is very poor with convection.

Euro4 and NMM WRF excel in my experience. 

That flow them uppers those heights.

There will be snow all over the east coasts.

December 2010 there was a full day 4 days prior to the event talking how dry it was then 48 hours before the euro4 picked up the streamers and showed 20cm widely.

The arpege is the only model anywhere near what we would expect

[Ice Day]

Beautiful at 120 - low gone under, cold still completely in charge

 

[Griff]

Happier down saf... 

[TSNWK]

1st low at 120 well under and better than previous run...now for the 2nd  chappy or chapess....

[john mac1]

2 minutes ago, TEITS said:

We should all sit back and forget about snowfall, breakdown of cold spell and marvel at the N Hemisphere chart at only +48. I have lost count how many times I have drooled at +384 charts but even those didn't match what we are seeing at +48.

Post of the year. This is what we chase every winter! Sit back relax and enjoy! 

[Mike Poole]

GFS pub run T120:

Just wow!  

Question is, will this run send the big low under - it might!!!!!

[Nath]

2 minutes ago, TEITS said:

We should all sit back and forget about snowfall, breakdown of cold spell and marvel at the N Hemisphere chart at only +48. I have lost count how many times I have drooled at +384 charts but even those didn't match what we are seeing at +48.

Gotta say it screams old school 1980s cold doesnt it. 

[seabreeze86]

GFS much further south with the low at 120hrs . Correcting south now when has this happened before 

[weirpig]

Pin point locations  to be determined    but you can see streamers  setting up all over the gaff 

[radiohead]

-10 uppers reaching the Atlantic, where they are -6 at the same time on the 12Z

Edited February 4, 2021 by radiohead

[Jason M]

1 minute ago, Griff said:

Happier down saf... 

Yup. first low ends up well down into France. Would never have guessed that was going to happen. Wouldn't be surprised if the second one goes that way too. Perhaps have to wait until tomorrow though.

[Johnp]

I think the low is going to be repelled on this run. Pressure rising out east....

[Battleground Snow]

Surface scandi high v monster low.

Place your bets please

 

[snowblizzard]

7 minutes ago, Ice Day said:

Sunday daytime highs!!!!

Probably 3c lower than it will actually be!

[GeordieX9v]

Just a 1070mb high. Nothing to see here.