Model Output Discussion - cold spell to end Autumn

[radiohead]

Bitterly cold windchill figures.

[nick sussex]

7 minutes ago, Daniel Smith said:

Blimey Nick, that almost sounds like a ramp.

No not yet! 

If it came off it would be very rare, maybe a weaker low is more likely.

The track and how far north the low gets is often not nailed down till within T72 hrs . 

 

 

[Dean E]

1 minute ago, Daniel Smith said:

ECM seems out of kilter with the shortwaves in the Atlantic, GFS and UKMO largely in agreement with their placement which is why they both go on to produce good blocking (or at least the UKMO would if we could see it further out)

I think we'll see the ECM backtrack tomorrow towards the GFS, though certainly unlikely to see another extreme run like the 18z, the only way from that is downgrade.

The only way is a downgrade with the GFS, because if there was an upgrade, god bless the servers at NetWeather.

Truely dreamy run from the GFS this evening, one area i've been still keeping an eye on is that NE area of the Pacific. 12z showed a hurricane force Low and the 18z is dropping it again. 

12z                                                                18z

   

The result, more time for pressure to build from the Pacific NW of the states and helping to build the Greenland High. IMO an area to continue to watch.

 

[John Cox]

32 minutes ago, MKN said:

Itl never happen. At +192 ish it has around 1% chance at best.

You might be right.

But in FI what we are looking for are trends and I am liking what i see. On a day to day basis of course beyond 7 days things will be different. At least we are not seeing mild south westerlies  

Edited November 28, 2017 by John Cox

[sawan]

3 minutes ago, radiohead said:

Almost enough to keep everyone happy!

Couldn't resist signing in to warn everyone, please take this output with a lorry load of salt. Otherwise it gets quite depressing reading through some of the comments. Not criticizing on this post of course

[Scandinavian High.]

No one knows we could be  in for coldest and snowest December since 2010. back to reality we are back on track for cold from north next week I expect more upgrades tomorrow ECM..

Edited November 28, 2017 by abbie123

[tight isobar]

18z is highly likely not to come off 'of course.

But as nick sussex alludes.

That zipping LP' IS around 60/40 atm.with 40% likely..and 60%unlikely.

And has flagged a couple of occasions lately.

So although the dramatics can highly likely be very diluted....the chance of some notable snowfall is improving.

And if the low keeps modeling, its track and movement is very open to question! Atm.

Edited November 28, 2017 by tight isobar

[bobbydog]

21 minutes ago, radiohead said:

This is with inland wind gusts around 100 km/h.

the replacement bus service is on standby for that day-

[weirpig]

1 minute ago, tight isobar said:

18z is highly likely not yo come off of course.

But as nick sussex alludes.

That zipping LP' IS around 60/30 atm.

And has flagged a couple of occasions lately.

So although the dramatics can highly likely be very diluted....the chance of some notable snowfall is improving.

And if the low keeps modeling its track and movement is very open to question!

60/30 mr isobar?  State education I presume?

[tight isobar]

Just now, weirpig said:

60/30 mr isobar?  State education I presume?

60/40 ..

Miss type pal.?

[northwestsnow]

Its  hard not to be seduced by runs like GFS18Z but i'd strongly advise  not expecting these kind of temps- but look at those temps between the wed - sat, this is midday temps

Absolutely going to be a huge outlier on the GEFS set..

[tight isobar]

Just now, tight isobar said:

60/40 ..

Miss type pal.?

Edit:

Corrected.

[Ice Day]

Having closely viewed the output, I suspect the 18z will be seen to be a mild outlier!

I think we've all been here before and are more than aware of the various pitfalls in taking these outputs too seriously.  However, there is a repeating feature of Greenland heights rising and some type of northerly affecting the British Isles around 6-7th December.  Having seen some of the posts on the 'Tweets' thread, there does seem to be something afoot.  

Experience tells me that if something can go wrong for the UK it generally does and I for one won't be surprised if it goes 'jugs up' on tomorrows runs, but at least we're in with a chance of seeing some proper winter weather over the next couple of weeks.

Back behind the sofa circa 06:30hrs before work!  Until tomorrow......

[Decemberof2010]

1 minute ago, northwestsnow said:

Its  hard not to be seduced by runs like GFS18Z but i'd strongly advise  not expecting these kind of temps- but look at those temps between the wed - sat, this is midday temps

Absolutely going to be a huge outlier on the GEFS set..

Hopefully a mild outlier?

[Thunder Snow]

22 minutes ago, radiohead said:

Almost enough to keep everyone happy!

Abit further north please :/ lol

[Met4Cast]

Important to remember that this is going to be OP led rather than ensemble/OP led. The models are trying to work out where the shortwaves are going to go and that's vital to getting the overall pattern. ECM has them further North which stops the progression of the high and we see everything move Eastwards. GFS/UKMO further South and well, we've seen what that brings.

The ensembles are good for a general guide, but they wont have a handle on this, even the higher resolution ops don't have a handle on this. I've seen entire ensemble suites flip in the space of a single run before.

[SMU]

GFS mean @126 shows a significant step towards the Ops this eve- with the control a carbon copy @126 as well..

Still enough time for the UK to escape victory & head for defeat though! although happy with the blocking forecast I gave which covers 6-12 Dec...

Edited November 28, 2017 by Steve Murr

[northwestsnow]

1 minute ago, Steve Murr said:

GFS mean @126 shows a significant step towards the Ops this eve- with the control a carbon copy @126 as well..

Still enough time for the UK to escape victory & head for defeat though! although happy with the blocking forecast I gave which covers 6-12 Dec...

Good to see you posting Steve, would it be fair to say tomorrows runs are going to be defining? Or could this turn into a saga, i say that because the handling of the Atlantic energy will be critical- and it might be a few days before we know where we are heading...

[weirpig]

Control looking very similar to the opp tonight  cold digging south 

[The Northern Ramper]

9 hours ago, Ramp said:

This could be a classic case of the models picking up a signal, dropping it and then finding it again.

We've just got to hope the extra 6hrs of data the gfs has had is enough for it to have a better handle on the shortwave.

The UKMO (which never bought the original path to cold and was proved correct) is it appears to be leading the way and the more consistent model.

 

Game on

Going as foreseen ?

[feb1991blizzard]

5 minutes ago, Steve Murr said:

GFS mean @126 shows a significant step towards the Ops this eve- with the control a carbon copy @126 as well..

Still enough time for the UK to escape victory & head for defeat though! although happy with the blocking forecast I gave which covers 6-12 Dec...

Yes, another GEFS upgrade coming.

[northwestsnow]

1 minute ago, weirpig said:

Control looking very similar to the opp tonight  cold digging south 

Looks a cracker - crikey i do hope GFS is sniffing the correct way forward here, somewhere could get very snowy if the low cuts across into the already cold air sat over the UK..Looks very much like GEFS have flipped cold...

Edited November 28, 2017 by northwestsnow

[Mucka]

GFS ensembles look solid enough with just a smattering failing completely and flattening out in hi res. 

Maybe the coldest set yet.

p1

LOL control run is better than the op

 

Edited November 28, 2017 by Mucka

[SMU]

16 minutes ago, northwestsnow said:

Good to see you posting Steve, would it be fair to say tomorrows runs are going to be defining? Or could this turn into a saga, i say that because the handling of the Atlantic energy will be critical- and it might be a few days before we know where we are heading...

 

I think in terms of allignment thurs 12z to start to pinpoint that track - that will put the time line at about 72-96 instead of 120-144.

confidence has grown tonight after this mornings problems - I left the MOD thread alone as wanted to see how the day developed !

control @216

EpIC -NAO/-EPO link up!

[northwestsnow]

1 minute ago, Steve Murr said:

 

I think in terms of allignment thurs 12z to start to pinpoint that track - that will put the time line at about 72-96 instead of 120-144.

confidence has grown tonight after this mornings problems - I left the MOD thread alone as wanted to see how the day developed !

control @216

EpIC -NAO/-EPO link up!

That looks amazing- sounds like Jason Furtado's latest tweet!!