Model output discussion - 21st Jan Onwards

[Derbyshire Snow]

I wish i could say that teleconnections were better, but because our region of the world weather is so difficult to predict, regional variations  can sometimes override teleconnections. It would be great to see negative AO or NAO and a SSW to split the PV , rather than just displace it. In the latter part of the GFS op i am hoping that this run proves we can get what we all want despite background signals not good.

Fingers crossed, taking a look at the run now from back of sofa

Edited January 27, 2016 by Derbyshire Snow

[booferking]

15 minutes ago, damianslaw said:

In the reliable timeframe UKMO performed far better than GFS during the recent colder spell (I used colder as it wasn't especially cold), GFS kept bulldozing in the atlantic far too quickly - something it does all the time, but yes it did eventually perform well when the atlantic did crash through.

Back to the models, well yes ECM certainly an outlier today, but it is showing the continued trend towards more average temps at least as we enter February with the euro high shunted away and the Jetstream moving along on a more southerly path. I will be surprised to see a quick development of heights in behind the trough as shown, but some amplification looks likely next week which should help build in some heights which combined with the more southerly jet could lock northern parts into a polar airstream at least, with spillage into southern parts on occasion.

We are already seeing evidence of less warm sector intervention as we head into the weekend, Friday now looking quite a cool day in the north, and Sunday is seeing a marked temp gradient between north and south enabling colder air to dig further in from the NW.

I'm expecting the models in the next few days to start offering up some much colder polar blasts in the 7-14 Feb timeframe..

Not so sure GFS was not to bad at all what i can remember in bringing in the Atlantic,  much closer than what the UKMO was showing there was a performance chart posting yesterday for that period and it spanked it ass. 

Anyway the GFS has trended slightly closer this run then goes pear shape from 150hr mark on-wards  we really need to see the GFS get rid of the PV strength over Greenland quicker between 120-144hrs and we will be in business.

Wait its having another go here we might get the split this run.

 

Edited January 27, 2016 by booferking

[snowangel32]

4 minutes ago, Timmytour said:

Then and Now...T150 v T144 on the GFS

    

Not too much difference...but what difference exists makes it better!   The Slug squeezed further south

Yes not alot of diffrence but slightly beter ridging. And the limpet slug getting pushed to the azores i am expecting a half way house scenario a blend between ecm and gfs wich still wouldnt be to bad. Not being fooled by ecm again and recently it seems as though gfs has handled shortwaves around the greenland area much better as the last cold spell confirmed. But as they say this is another round and surely us coldies must get a knockout at some point. So cmon ECM.

[Mucka]

GFS 18z still keen to turn out turgid dross, hope it's wrong.

[Banbury]

2 minutes ago, Mucka said:

GFS 18z still keen to turn out turgid dross, hope it's wrong.

You are living off one model though, it certainly isn't set in stone and clearly the Beeb have backed the Euro's tonight ..............time will tell of course

[Lukesluckybunch]

The 18z looks pretty cool to cold up to 200 hours am I right in saying?

[Derbyshire Snow]

That jet stream out of US again is relentless and is going to smash straight through the atlantic ridge i believe, Not liking this run at all. I am sure we will get a teaser at the end again. Keep us all to come back tomorrow

 

One positive, we are losing the heights over Europe

Edited January 27, 2016 by Derbyshire Snow

[Daniel*]

I'm liking what the Jet Stream is doing on GFS 18z.

[Banbury]

Clearly GFS nothing like ECM or UKMO , the professionals are siding with the Euro's be interesting to see how this pans out

[Derbyshire Snow]

Later in the run the high in the Atlantic is trying to ridge north instead of defaulting back in to Europe. If we could only get a good strong Greenland high then we could have a block on our hands

 

A nice end to the run i feel is coming

 

oop! just seen the end. bad call. There always next time

Edited January 27, 2016 by Derbyshire Snow

[Banbury]

JMA is trying very hard to follow ECM

[Banbury]

120 fax shows a Northerly trying to develop

[Daniel*]

GFS is having another go, with amplification in North Atlantic, pesky lobe puts a stop to decent ridging.

Edited January 27, 2016 by Earnest Easterly*

[Derbyshire Snow]

Conclusion.

I was trying to look for positives in this run but deep down in my heart i knew with the very strong jetstream, it was going to be difficult to halt it. Flattered only to deceive mid run. A bit disappointed but the ensembles might be better 

 

SSW, we need you. Lighting a very big bonfire in back garden, see if it will help

Edited January 27, 2016 by Derbyshire Snow

[Frosty.]

The Gfs 18z is making baby steps towards the Euro models with much colder weather digging south next week with ice days across Scotland, lots more changes to come and hopefully for the better...It's noticeable on this run how it's always trying to reload cold shots well out into FI. Tomorrow I hope we see the ecm / ukmo carrying on from where they left off this evening and the gfs fully on board by then, not too much to ask is it?

[Singularity]

2 hours ago, nick sussex said:

You can't ignore the other shortwave because its positioning is related to the overall good to bad of the upstream pattern.

The output that clears that shortwave further east from the main trough and gets high pressure over the top will then of course have the better pattern going forward. And the ECM is best, UKMO next, GFS worst.

Thanks Nick, I'm glad that's been cleared up - your wording had left me looking purely at whether that shortwave moving near the Azores merged with the U.S. trough or not, as opposed to the extent of separation and its relation to the extent of the ridge building over the top. This amended view makes a lot of sense  - and don't worry, past experience means I know better than to completely ignore what a particular shortwave is getting up to 

Also, it's good to know that NCEP looking down on the GFS runs of late, it's very encouraging given the significance of the U.S. pattern for our cold/snow prospects

 

Oh and the notion that the upstream amplification leads the behaviour of the shortwave south of Greenland is something I tried to put across in my GFS analysis and then forgot about when adding that bit about the ECM/UKMO... got too caught up in the shortwave drama  Signs that I should try and get a good night's sleep I think! 

Edited January 27, 2016 by Singularity

[Panayiotis]

Does anyone know where I can find current GLAAM graphs? 

[A.J]

let's discuss the models please..................any posts that require action will be looked at by the moderating team in due course. Members are requested to keep on topic at all times, use the report function for questionable posts and leave the moderating etc to the relevant NW team.....thank you

[Jason M]

Methinks some posts might vanish in the morning . Come on guys lets all play nicely as its been much better on here this winter and it's too late in the evening to expect the mods to be tidying up.

Anyways, bit more interest in the GEFS tonight. They aren't a great set, but much more scatter tonight and a less strong Iberian heights signal. So, IMHO we are still very much struggling but there is some hope this evening and it's not often that we've been able to say that. 

 

[A.J]

a couple of posters simply aren't listening.....read my post and take in on board......now, move on, nothing to see here!!

[weirpig]

This is the image i would hope to be shown again in the morning  a wonderful chart for snow  and not that far into fi.   Lets hope the gfs starts to come a little bit more on board tommorow (today)

[A.J]

thread now tidied up....let's keep it that way folks 

[Polar Maritime]

The GFS continues to show a cool/cold weekend with the risk of snow almost anywhere bar the far South as -7/8 uppers get pulled in from the N/W. Into the new week after a brief milder interlude, Another cool/cold shot from the N/W (maybe turning Northerly as shown by ECMWF) as the jet pushes South with this theme continuing into the run, So a much more seasonal outlook than of late with average temps for the time of year.

Edited January 28, 2016 by Polar Maritime

[Ali1977]

Whilst this mornings ECM is still chilly next week, it is no where near as good as last nights unfortunately. Still, chances of wintery showers Midlands northwards is still there.

[bluearmy]

ECM loses that runner which shouldn't be too much surprise as there was poor ens spread support for it.  Perhaps a little bit short range for it to pop back up now but can't be discounted. Without this trigger feature, the cold cannot advect South and the undercutting system to follow does so into air that isn't cold. 

Whilst day 9 charts are not for too much discussion, I do like the NH profile re vortex and Arctic high placement re cold prospects thereafter.