Model output discussion - mid January

[Ice Day]

Well since the high point of last nights 18z, it's all been a bit underwhelming (yes, I am understating affairs).  GFS has reverted to blowing up mega lows in FI with a 935 low to the west of Iceland at 222

 

[Daniel*]

Resumption of cold PM flow at day 4 more normal service this winter - widespread showers, falling as snow on high ground although not entirely so, just high ground of the north. Models have upgraded this cold snap with greater amplification to W. 

Edited January 27, 2018 by Daniel*

[igloo]

13 minutes ago, Ice Day said:

Well since the high point of last nights 18z, it's all been a bit underwhelming (yes, I am understating affairs).  GFS has reverted to blowing up mega lows in FI with a 935 low to the west of Iceland at 222

 

Its more likely than not im afraid its not called the icelandic low for nothing i used to think feb was the time when the PV started to weaken but over the past few years it has not been happening its just the way it is nowadays sadly

Edited January 27, 2018 by igloo

[Daniel*]

GFS up to it’s usual tricks blows up a sub 930mb snow ‘hurricane’ this probable over egg is important for developments to north/east. On the fact of chart below it looks quite encouraging, just out west needs to be toned down.

Edited January 27, 2018 by Daniel*

[bluearmy]

Ec  spread and op from the 00z are also reasonably supportive of low heights up there days 9/10. not surprising to see the gfs op there. 

 

[Daniel*]

@blue It looks pretty on the extreme side probable it won’t be as berserk as that.

[Daniel*]

Whilst GFS 06z toned it down the 12z goes the other way vortex hopefully shunned away NW into Canada..

[snowray]

This is the 3rd bad run in a row for coldies from GFS, IF, and I say if it were to verify our cold would be pushed so far away east that we would have no chance of a cold easterly this February, as others have said more chance to look north and maybe a decent toppler could be more likely.

 

Edited January 27, 2018 by snowray

[bluearmy]

Just now, Daniel* said:

@blue It looks pretty on the extreme side probable it won’t be as berserk as that.

That gfs op is pretty good wrt to the gefs and eps through week 2. ends with heights dropping se across the Atlantic and rising to our east. It might not evolve like you want it to but it’s far more likely to verify than some of the eye candy over the past few days. Although that’s the mean picture be8ng reflected,  the clusters show more wintry soltuons still on the table. 

[bluearmy]

6 minutes ago, Daniel* said:

Whilst GFS 06z toned it down the 12z goes the other way vortex hopefully shunned away NW into Canada..

I’m keener on the heights tbh .....

 

Day 16 though ......

[jvenge]

2 hours ago, Steve Murr said:

Here’s a poser then

the GFS for a day or 2 had a Scandi high well before your lagged time - A model doesn’t forget things - so unless it was being progressive by 10 days / 2 weeks then it goes against what your indicating..

so vis a vee at that point the MJO was necessary driving the GFS output-

 

in terms of GFS being the only data source available for some quite important plots that’s like school kids taking turns picking their football teams & the GFS being the last one picked because it had to be picked- doesn’t make it any good-

I tend not to subscribe to the belief that models at days 13 or so are infallible. Also, i don't worship the MJO. It is a catalyst to change, but not a sure thing.

But you can also achieve a Scandinavian block through a shallow movement from phase 1-4 of the GWO under La Nina conditions. (Tease since end of December in the models). GEFS was also much more bullish in its GWO forecast going phase 4 much quicker than it actually did. Even 5 or so days ago it thought it would happen then, but only managed it the last 24 hours. I personally view GWO forecasts as unreliable even at T24.

Also, ridging or MLB is to be expected in La Nina conditions. Since a HLB comes from that ridging initially, you have a multitude of opportunities for models to get things wrong. 

I can't predict the future of how the GWO will move through its phases and we are all more ignorant than a few days ago due to that loss of data, but I personally think we will see at least another easterly tease in days 10-15 shortly and if things continue as recent data suggested, maybe more than a tease. 

 

[feb1991blizzard]

GEFS mean now as flat as a pancake even out to 264, another chance gone I'm afraid.

[OfficialKevWX]

2 minutes ago, feb1991blizzard said:

GEFS mean now as flat as a pancake even out to 264, another chance gone I'm afraid.

Gone is a strong word, there is huge uncertainty after Day 6, so I wouldn’t discount more flipping within OP runs

[feb1991blizzard]

2 minutes ago, OfficialKevWX said:

Gone is a strong word, there is huge uncertainty after Day 6, so I wouldn’t discount more flipping within OP runs

I don't mean thw whole thing, just this earlier than expected chance - FI even in these last 2 downgraded suites has offered something but its just like those charts at xmas now where the ridge is there but the PV just too strong.

DEFO nothing before 384 now IMO.

Edited January 27, 2018 by feb1991blizzard

[karlos1983]

Updated MJO still looks good

 

[That ECM]

4 minutes ago, feb1991blizzard said:

I don't mean thw whole thing, just this earlier than expected chance - FI even in these last 2 downgraded suites has offered something but its just like those charts at xmas now where the ridge is there but the PV just too strong.

DEFO nothing before 384 now IMO.

A good dry out for many for the most part. I don't mean members in here

[feb1991blizzard]

2 minutes ago, karlos1983 said:

Updated MJO still looks good

 

Showing signs of dying a death before getting into 8.

[feb1991blizzard]

Good support from the ensembles for the op strat evolution which is good news going forward.

[bluearmy]

44 minutes ago, feb1991blizzard said:

I don't mean thw whole thing, just this earlier than expected chance - FI even in these last 2 downgraded suites has offered something but its just like those charts at xmas now where the ridge is there but the PV just too strong.

DEFO nothing before 384 now IMO.

The spread at T264 isn’t flat though ...

 

Edited January 27, 2018 by bluearmy

[tight isobar]

A perfect example via 12z ec-mod..

Note the rounding of diss-aligned AZHP..

And the pm flow....

Not to mention the now polar height form..

Again i'll elaborate shortly..as things stand firm!!!!

Edit;..

MJO. looks key to overiding factors....

And forcing-may be overcoming nina cond!!

Edited January 27, 2018 by tight isobar

[feb1991blizzard]

1 minute ago, bluearmy said:

The spread at T264 isn’t flat though ...

 

Hmm - I'm not a big fan of spreads tbh, the GEFS actually did look decent still in Graph form but probably the reason for the spread as well is that there have been some (admittedly fairly potent) NWerly incursions with some ridiculously low heights to the Nw and W, the reason I don't like spreads is it only takes one outlier to skew the whole thing, I admit though after the suite was fully out, Ive backtracked to the extent where it wasn't as bad as id feared but like I say, that's due to some -6 / -7c PM incursions.

[tight isobar]

A picture paints a thousand words..

Lets see where this goes....

Its a freezer run....

[feb1991blizzard]

1 minute ago, tight isobar said:

A picture paints a thousand words..

Lets see where this goes....

Its a freezer run....

It barely gets the -6c isotherm into Britain and likely wont do much better throughout the whole run.

[Daniel*]

55 minutes ago, karlos1983 said:

Updated MJO still looks good

 

Indeedy... steady as she goes less so for NWP, while MJO should not be taken in isolation it is promising. Model fatigue has really set in. Come on folks we’re nearly there - for la freeze. 

May have the remainder of the weekend off, and see what new week brings a much clearer picture will be identifiable by this time next week; the new week ahead will be the most crucial of the winter.  

 

Edited January 27, 2018 by Daniel*

[SMU]

ECM has the biggest wedge of heights ahead of the Atlantic @144 - there’s has the biggest chance of holding the Atlantic off come 192

lets see how the run develops

 

Edited January 27, 2018 by Steve Murr