Model output discussion - Post SSW - Will it turn cold?

[Mike Poole]

Where do we go from here?  

My starter for 10 is the low 1500 miles east will strengthen the block, the low west of Ireland can only go under, the result a mega Ely - again.  Could be wrong mind!

[Banbury]

Yes 18z still good 

[nick sussex]

2 minutes ago, blizzard81 said:

Being the weather geek I am, I have noticed over the years that those fax charts are only ever modified against the ukmo raw at around the 3 day timeframe. Days 4 and 5 (the late evening updates) always mirror the ukmo raw. 

Perhaps Friday is pub night at the Met Office and they just rush to get out ! 

I would be shocked if the UKMO is correct against the ECM op and mean at day 4.

Even the GFS is much better. We’ll see in the morning .

[blizzard81]

1 minute ago, Mark wheeler said:

Genuine question, can anyone recall the last time it didn’t and the reasons why?. 

Can't recall the 96 or 120 fax charts diverting from the ukmo raw in recent times but the 72 and 84hr charts have been modified over the last couple of days - to ecm and icon way of thinking. 

[Southender]

My rather simplistic view is the cold is coming next week whatever way you slice it. It’s a case of whether it’s mid week or later in the week. When it arrives we will all know about it and for some, remember it for a long time...

[Banbury]

Decent again from GFS

[blizzard81]

Just now, nick sussex said:

Perhaps Friday is pub night at the Met Office and they just rush to get out ! 

I would be shocked if the UKMO is correct against the ECM op and mean at day 4.

Even the GFS is much better. We’ll see in the morning .

Lol, I think every night is pub night at meto as like I say, the late night 96 and 120 charts are always carbon copies of the ukmo raw output. 

[ICE COLD]

The cold is getting closer on the pub run ?

BIG EASTERLY INCOMING ???

Edited February 16, 2018 by ICE COLD

[chapmanslade]

2 minutes ago, Mark wheeler said:

Genuine question, can anyone recall the last time it didn’t and the reasons why?. 

Well on my Met office open day visit last week they said the UKMO model is the best up to 3 days, together with ECMWF which slightly out performs it, in the UK. This latter part being bold for a reason as in other parts of the world it isn't always the case. Plus in general in the 72hrs area the spread of models is usually fairly tight so differences not massive. What was interesting was the suggestion they gave that model definition was unlikely to improve much further as 'computing power' is not really the limiting factor - data density at T0 is.

[Allseasons-Si]

THAT is one staggering cold pool out to the east,colder than the 12z

[lorenzo]

1 hour ago, lorenzo said:

Twitter is amazing to get the insights from the pro's I was lucky enough to catch this discussion today between Mr Masiello and Dir Mike around MJO programming and how it could be improved.

 

Point here is the analog for the MJO imprint that Dr Ventrice creates is probably the best in class the weather community has - and, just look at what is says...

 

 

For all the confused emoticon responses - this is a bona fide greenland high being programmed as a result of the MJO wave analogs- hope that helps 

[blizzard81]

Big trend since yesterday's ecm 12z op for brutal cold to head towards us - yes 'us' from Russia. Amazing model watching at the moment. Absolutely intoxicating! 

[Mike Poole]

And straight on cue, here the Ely comes

All roads lead to cold?

Edited February 16, 2018 by Mike Poole

[bluearmy]

4 minutes ago, Mark wheeler said:

Genuine question, can anyone recall the last time it didn’t and the reasons why?. 

It has in the past. Can’t say I’ve had much practice over the last few years checking day 5 faxes religiously!

and the Beeb aren’t the met office any more so that conduit is now shut. !   We could yet see the slightly slower route verify which would be around day 8 for the deep cold to reach us. 

It  should be noted that the 12z eps suite was a little less cold than the previous one and the largest cluster went a bit Atlantic in  the extended as low euro heights faded a bit and allow an upper flow south of west to establish - not unlike the wording of the ukmo extended but a little quicker. the geps also seemed a bit less sure. Suspect this could be down to the next downwelling wave messing with the modelling. 

[Deep Snow please]

3 minutes ago, Allseasons-si said:

THAT is one staggering cold pool out to the east,colder than the 12z

Looks a bit dry.

[lorenzo]

Interesting....

Got challenged on this post being off topic - best I add in some more commentary - apologies 

This shows the lagged SSW artefact and the effect of the vortex split via the weaker vortex segment and propagation into our locale, given the nature of the split I think the cold element shown here is not in question - it is the nuance of the wave breaking and how that supports the manifestation of the block.

Given the last 48 hrs of modelling and the flip with the wave breaking - I thought my initial post of > cold arriving > interest in evolution with sufficient support from the ECM 12 z would explain, sorry if not!

simply put we see the gfs 18z follow the ECM programming for the transfer of cold, how we get here open to interpretation but having to my earlier posts point the best verifying model known to man on board is good, plus an ensemble suite backing this - also good - hope that explains

Edited February 16, 2018 by lorenzo

[ICE COLD]

Better late than never ?

Edited February 16, 2018 by ICE COLD

[chapmanslade]

4 minutes ago, johnholmes said:

I don't mind you posting tripe A but I draw the line when honesty is lost.

BBC forecasters yesterday and indeed for several days, at the end of each forecast I have watched, have mentioned it turning much colder, I believe was the phrase they each used.

 

Indeed so - I posted last Saturday that the Met office forecaster I was speaking to said 70% chance of cold after this weekend which was in his words a very high degree of certainty at that range. That obviously leaves 30% chance of it not doing so. 

[Allseasons-Si]

Holy cow

not far off now.

[MattStoke]

Slower to deliver the easterly on this run, but a much deeper cold pool being 'tapped into'. 

[blizzard81]

1 minute ago, lorenzo said:

Interesting....

Very similar to the ecm op

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

41 minutes ago, kold weather said:

Also just to note some of the absolute coldest ECM ensemble runs don't really get any easterly thrust going until about the 25th, but they really are severe once the cold air floods west. Coldest run gets *-20C* into Kent!!

What number is the - 20 run? Tcheers

[Nick F]

Pretty overwhelming support for ridge to build to the N and NE from the 12z EPS clusters

T+144

T+192

Be interesting to see in the morning if EC sticks with the quicker build of pressure to the NE and introduction of the easterly and GFS comes on board or sticks with it's slower evolution to an easterly. Whatever way, the Atlantic is hitting the buffers and blocking will be in control, just need to see some agreement on where the block sets up exactly. But given the 12z EPS guidance, block over Scandi seems favourite atm.

Edited February 16, 2018 by Nick F

[Man With Beard]

Not all plain sailing on the clusters - a 20% cluster sticking to this morning's GFS solution.

But of course that means 80% on the cold side.

Perhaps a little too soon to be exploring D11-D15, but it still looks like a NW height rise is the overwhelming favourite:

The daffodils won't like that!!

[Southender]

ECM too quick and GFS too slow?

Middle ground scenario on the arrival?

Cold spell begins this time next week give or take?

Watering down on the depth likely. But, it’s coming...

Edited February 16, 2018 by Southender