Model output discussion 25th Jan - The final third of winter beckons..

[MR EXTREMES]

On 1/26/2017 at 04:42, Rocheydub said:

Very well aware of its origins ad it's meaning. Thanks.

I'm afraid you'll be sadly disappointed!

http://www.meteociel.fr/modeles/ukmo2.php

not sure what u mean ukmo been rock solid and the latest gfs is much better across the country.

my nerves are really shredded the quicker it gets here the better i just want a easterly dont care about the details atm just get the beast or at least something wintry in.

[MattTarrant]

The difference between the 00z and 6z is remarkable. Note less energy coming out of Greenland! 

First chart is 210h on 6z and second is 216 on 00z. 

 

Edited February 5, 2017 by MattTarrant

[numbnutts(uk)]

1 minute ago, Kentish Snowman said:

Cold to the left of me freezing to the right here I am stuck in the middle with snow!  

lol showing your age

[TEITS]

Im expecting some epic +300 charts, maybe the holy grail of winter synoptics.

[Matthew.]

Great 6z run. Much better than the ECM 0z for very cold and snow from next weekend

[Jason M]

7 minutes ago, MR EXTREMES said:

not sure what u mean ukmo been rock solid and the latest gfs is much better across the country.

my nerves are really shredded the quicker it gets here the better i just want a easterly dont care about the details atm just get the beast or at least something wintry in.

 

This run upgrades us from poodle to slightly miffed Alsatian. We're a bit off beast yet. 

 

Gefs will be interesting!

Edited February 5, 2017 by Jason M

[EML Network]

Well it's been a long time since I saw this, the whole of the UK blanketed in snow

shame it's well well welllll into FI territory, but it's a beauty to behold none the less

[shaky]

Even the arpege model has everything slightly further south and west compared to the 00z run!!

[northwestsnow]

Well forgive me father as i have sinned teits was spot on earlier i thought it was going wrong but thats one stellar gfs6z! 

I think we will all be happy if that comes off, cold, cold and more cold!!

[snowray]

By T300, cold easterly, not the mild muck one that ECM showed.

[KyleHenry]

13 minutes ago, Steve Murr said:

The beast is coming on the 06z

Agreed. We had to wait for the -AO to dissipate and allow the Trop PV to migrate away from E Canada/ Greenland 

The Scandinavian HP holds throughout this process and emerges resilient.

 

The Azores has another route option. Greenland. 

 

[Singularity]

Disrupting Atlantic versus decent continental cold pool.

Serious feedback action at work here from those slight adjustments in the 3-4 day range.

This is essentially the ECM 00z with the low closer to the S Thu-Fri (not so good) but not nearly as much flattening of the big block by the Atlantic jet (much better!).

  

The advance of the vortex on Siberia is much more advanced on the 06z and this helps us out by focusing the block over Scandi rather than C. Asia.

That's the thing about ECM - it's been showing a vortex shift that could really help us out, but whereas the 12z yesterday introduced upstream amplification fast enough to hold back the Atlantic again before the block is flattened much, the 00z was too slow to introduce that drop out of westerly momentum.

I must say though - I'm not sure how the block has become quite that strong and high in latitude on the 06z run. Perhaps the much more expansive and deep cold pool drives a regional feedback to sustain sinking motion there?

See now this really is the ECM 00z at day 10 but with the block not remotely flattened; you have the low to our S and the stalling one by Iceland.

Okay - must cool it, I actually became a bit excited for a change  We really need to see ECM drop that idea of flattening the block. Essentially we have GFS dividing up low heights far better than ECM, when it's usually the other way around! Or at least it used to be; for the 3rd week easterly in Jan it was ECM at the longer range that was keeping the flow too smooth that allowed an elongated high so far east with such a good easterly flow on the S flank. In the end the flow buckled more and, unfortunately for us, the blocking became more focused in one region and not the best for us to benefit.

So yeah. More food for thought. Enjoy your Sunday everyone, I'm off out for some fine food 

 

[Zakos]

We have seen blocking events in winter as shown above, however the blocking has been mostly mid-latitude blocking, and and unfortunately not positioned well for the UK.

What we are seeing now is different. - True northern blocking

The block is appearing more resilient (overall) each day This is by far the most promising event of winter In terms of potential for a noteable spell of cold.

 

 

Edited February 5, 2017 by Zakos

[Frosty.]

6z is a cracker for coldies, like I said earlier, the general trend so far today is very good for cold from the east and its still taking shape..could be a prolonged cold / very cold outlook!

[Ali1977]

I hope the Op run has some GEFS support, they've been at odds lately and now would be a good time to change that - I don't mind the Op being on the warmer side obviously!! 

[summer blizzard]

The 6z is a much better run because of the handling of the secondary low which develops near day 10. On the 6z it is closer to the UK and a bit further east which lowers pressure a bit and brings more of a ENE component (this is backed by the Euro ensemble mean). The problem the 6z has until well into FI is that the low in question then sinks south instead of heading towards Italy so we have to wait for the Atlantic to undercut again (albeit that does raise snowy possibilities). 

 

[Gowon]

The gfs is nearly an epic run..You can see the more positive anomalies to our NW and NE  but there's a little hang back over Greenland and Iceland. It stops the high and the extent of the cold air reaching us from the East later on... Still a good run though.

 

Edited February 5, 2017 by D.V.R

[mulzy]

Significant westward shift in the 06 GEFS at only 78 hours

 

[feb1991blizzard]

You all know what this chart means people don't you?

 

2013 revisited!!!

[SMU]

Finally after being patient & forecasting the GFS to be poor- we are starting to see the upgrades-

Ensembles starting to spring up like this at T78 showing the upper air cold pool hitting ALL of the UK ( PTB 12 ) -

* Note the perfect allignment & thicknesses 8-12 DAM lower than earlier forecasts 

S

Add PTB 5 ( nearly ), & 9

Edited February 5, 2017 by Steve Murr

[Paceyboy]

Crikey I would take the money right now and bank the 6z GFS. Snow chances for most from this Wednesday to the end of the run, absolutely no milder days there away from the extremities 

[bluearmy]

Interesting op GFS run in that it follows the theme of the extended GEFS anomolies from the 00zby dropping an upper trough between the scandi high and growing mid Atlantic feature .  So the question of how does it for with the GEFS should be OK judging by the previous suite

[booferking]

The mean has the high further NW also great.

[Seasonality]

1 minute ago, feb1991blizzard said:

You all know what this chart means people don't you?

 

2013 revisited!!!

!!!!! I remember that well. In Warsaw on easter Sunday on 31 March there was a 15cm+ snowfall. And snowing here now... It is 6 degrees colder than was forecast mid last week.

[nick sussex]

At least the easterly isn't disappointing in terms of how much drama it can cause.

After a somewhat underwhelming ECM output good to see the GFS 06hrs run upgrade the cold and not follow the ECM with that bulging PV to the nw.

The differences are really in relation to how much flattening occurs of the high which is the result of how they handle the movement of the PV east/ne. The GFS 06hrs run has that sharper troughing to the nw which takes the jet further ne so less pressure on the high and that would be more in line with the MJO progression.

If we didn't have that MJO on side I'd be more inclined to back the ECM but in this case I think its piling too much energy over the high.