Model output discussion - is the beast awakening?

[Timmytour]

10 minutes ago, s4lancia said:

By the same token nor is a Scandi High any guarantee (i'm thinking the dreaded 'no mans land' scenario for one). I'd wager Scandi highs probably produce way less than a proper Greenland High.

I remember a time in the 70s when I would walk to the library trying to will it to snow.  It was certainly cold enough but all we got in forecasts and, from my memory of that time, all we saw was flurries of snow.... you could comfortably count the flakes as they fell but they neither wet the ground nor changed its colour.  I remember it as a very frustrating time and can only imagine we were under the influence of a Scandi high at the time but the pressure was too high to generate any convection.

[Yarmy]

17 minutes ago, Battleground Snow said:

It's about 2-3 millibars, less deep, I think we are starting to lose the plot with this micro analysis

Where are you getting the ECM 6z data from? I thought it was hidden behind paywalls.

[Updated_Weather]

Whilst we await 12z.. anxiously may I add! 
my weather apps(not to be taken literally) have now adjusted for barely above freezing come the weekend with snow appearing.. as unlikely as it may happen like this, it’s nice to see

[Updated_Weather]

2 minutes ago, Updated_Weather said:

Whilst we await 12z.. anxiously may I add! 
my weather apps(not to be taken literally) have now adjusted for barely above freezing come the weekend with snow appearing.. as unlikely as it may happen like this, it’s nice to see

Also 4 reputation away from 1000

[Cold Winter Night]

16 minutes ago, s4lancia said:

By the same token nor is a Scandi High any guarantee (i'm thinking the dreaded 'no mans land' scenario for one). I'd wager Scandi highs probably produce way less than a proper Greenland High.

 

10 minutes ago, Valleyboy said:

Not true, you are probably thinking of a Russian high, which can be a party spoiler.  If you look at history, you will find Scandi highs are generally involved in Uk winter freeze ups.

To get the coldest T2m's and T850's a well developed Scandi High is necessary in most cases.

Many of the best Greenland Highs of the past actually developed out of Scandi Highs that moved to Greenland through retrogression.

Most memorable cold spells that are mentioned almost daily in this thread came to us through Scandi Highs.
Think late December 1962, late January 1947, February 1956, February 1991, to name a few.

[Updated_Weather]

1000! Reputation

you know what that means? 12z are going to all be in agreement -12 850s and widespread drifting snow incoming!

[Notty]

Complete scatter after 5th Feb. I doubt we will be any the wiser until that LP sorts itself out later this week.

 

Edited February 1, 2021 by Notty
Corrected

[Purga]

METO not expecting any mild victory anytime soon.

"The tussle of air masses over the UK continues this week and it looks like the cold air will be victorious... eventually"

[Battleground Snow]

18 minutes ago, Yarmy said:

Where are you getting the ECM 6z data from? I thought it was hidden behind paywalls.

It is,  but this website gives us a snippet.

weather model ecmwf model - united kingdom - surface pressure [base + 72] | weatheronline

WWW.WEATHERONLINE.CO.UK

---

Weather for UK, Ireland and the world. Sailing, Marine Weather, Weather maps, radar, satellite, climate, historic weather data, information about meteorology, reports, weather warning.

 

[Paul]

NCEP have approved the GFS V16 and last I saw weren't expecting any science updates. What's caused the delay, as I understand it, is the IT stability test that they run which has to go for 30 days, but stopped part way through during January so will need re-starting again across another 30 days. 

There's loads of info here:

GFSv16 Official Evaluation

WWW.EMC.NCEP.NOAA.GOV

 

[Blessed Weather]

45 minutes ago, IDO said:

I got this from my own research from verification stats, for instance:

At d10 on 12z verifications the gfsP ranks below the older less upgraded version. That should not happen with a large 31-day sample from a "better" model! If you look at the reason you can see runs that fall out of standard deviation, for example on heights, a 0.3 when the average is 0.6. This occurred too many times for it to be just random, and it is fair to conclude that in certain situations the model misfires. They need to correct this and in January when I mentioned this, other members said it was due to come on line in February! I said that this would not be allowed to happen and it was obvious that there was issues. So I am not surprised that there has been a significant delay.

NB. It seems to perform better earlier, say at d5, which is expected as it is an upgrade!

Thanks. Interesting that NOAA stats show v16 better than current v15 GFS at Day 5 but your verification stats suggest it's worst at Day 10. I also note that the current v15 GFS performs better than ECM at Day 10 in one of your charts. Have you a link to those graphs/stats as I don't appear to have it saved (pm if you like IDO). Maybe best if we move on then, rather than clog the thread further.

[IDO]

5 minutes ago, Paul said:

NCEP have approved the GFS V16 and last I saw weren't expecting any science updates. What's caused the delay, as I understand it, is the IT stability test that they run which has to go for 30 days, but stopped part way through during January so will need re-starting again across another 30 days. 

There's loads of info here:

GFSv16 Official Evaluation

WWW.EMC.NCEP.NOAA.GOV

 

That was last updated on Jan 27 and says that implementation date is March 2021. This has been superseded by what @Blessed Weather posted, a delay until December 2021! The Para has been going again for a few days and I suspect that it will be running simultaneously through the next nine months or more with the current gfs?

Link for verifications: https://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/

 

[Updated_Weather]

Do Mods think it'll be a good thing to start a new thread for 12z as we are already at 100 pages?

[Ali1977]

Icon delaying the cold, it’s definitely not here by Friday even in Scotland - hoping the UKMO and GFS don’t start that game even more!! 

[Griff]

Judah Cohen just posted these which might cheer up a few south of the wall... 

Link to tweet is in the tweet thread as usual. 

[Updated_Weather]

4 minutes ago, Ali1977 said:

Icon delaying the cold, it’s definitely not here by Friday even in Scotland - hoping the UKMO and GFS don’t start that game even more!! 

Think we are all glad that it's the ICON xD

[Battleground Snow]

Icon weakens the low and is better with the Scandi trough extention but it still takes until 132 to get the cold in.

[Cavehill Snow]

4 hours ago, Weathizard said:

High pressure nudging in from the south east ruining everything, how is it that as soon as the ECM hops on board the steadfast GFS jumps off? This always seems to happen.

I have noticed this before also. Perhaps in complicated set ups with conflicting signals, the EC with its higher resolution and larger number of vertical layers may be seeing potential knife edge situations and resolving them at an earlier timeframe than before GFS spots the same scenario. Only a theory, i have no data proof.

[sheikhy]

3 minutes ago, Battleground Snow said:

Icon weakens the low and is better with the Scandi trough extention but it still takes until 132 to get the cold in.

Better than the crappy gfs 06z!!

[Updated_Weather]

1 minute ago, sheikhy said:

Better than the crappy gfs 06z!!

Yep and ICON isn't a great model! - Says a lot!

[Cold Winter Night]

4 minutes ago, Battleground Snow said:

Icon weakens the low and is better with the Scandi trough extention but it still takes until 132 to get the cold in.

This setup looks very much like UKMO this morning. Especially to the North, in the Atlantic and the ESB.
 

[IDO]

What we want from the gfs to stop a total fail is how the 0z modelled that low at d6:

0z>06z>

The gfs 06z did not ride the ridge and merged with the sinking low and blew it up killing the pattern. The ICON is not as progressive with that low but sends it in that direction (as 06z). It is still recoverable but complicates the pattern, whereas the GFS 0z was clean and will let the easterly arrive unencumbered.

Edited February 1, 2021 by IDO

[Battleground Snow]

South rejoice at 180. It's going to be a long evening

[sebastiaan1973]

Excellent run from ICON12h. Cold, easterly winds across the North Sea.

[ptow]

18 minutes ago, Griff said:

Judah Cohen just posted these which might cheer up a few south of the wall... 

Link to tweet is in the tweet thread as usual. 

What is that showing - temp departure from ave?