Model Output Discussion 29th December - Into mid-Winter.

[Jonan92]

You should see the bactracking of the GFS in this run

 

From this (18z)

To this (00z)

[Cheshire Freeze]

12 minutes ago, Jonan92 said:

You should see the bactracking of the GFS in this run

 

From this (18z)

To this (00z)

Yep, another quite significant backtrack from GFS on the 0z

[snowfall09]

UKMO not looking too bad @ +144h 

[Cheshire Freeze]

1 minute ago, snowfall09 said:

UKMO not looking too bad @ +144h 

Not too bad is an understatement!

Deepish troughing to E and strong ridge going up over the top. As good as earlier ECM...

[SMU]

From 12z 174 - 168 18z to 162 00z the GFS is getting there..

superb 144 UKMO

boom

S

[Met4Cast]

00z much, much closer to the ECM/UKMO solution, not quite all the way there but I think the 6z will probably complete the backtrack. Remarkable how the ECM has been so consistent and seems to have called this one right. For once, it seems the colder solution might actually have been the correct solution.

[NO LONGER POSTING]

Round she comes 

18z

00z

 

[Mucka]

35 minutes ago, Steve Murr said:

From 12z 174 - 168 18z to 162 00z the GFS is getting there..

superb 144 UKMO

boom

S

Great to see. This mornings GFS, UKMO and GEM are all more amplified and further West than their previous run so all good news prior to ECM.

It would be fantastic to see ECM stick with last nights output or raise the cold stakes even higher in the form of a stronger Easterly rather than slack continental flow but that looks as though it will be very hard to achieve unless we can trap and have some energy returning West under the block which could fuel the trough trapped over Europe.

Also will be looking for amplification in the Atlantic against any block day 9/10 as that could lock us into a very prolonged cold spell with high eventually retrogessing toward Greenland - that would be cake and eat though and looking forward to the much nearer time-frames and seeing some snow. 

 

Edit

Can add JMA to that list as well. Much better than previous run and slightly better than GFS at same time IMO.

It looks as though we now know where the floor of this cold spell is and it is still slowly being raised.

We don't yet know where the ceiling is though.How high can we go?

Edited January 10, 2017 by Mucka

[Man With Beard]

GEM also close to an easterly at T192.

Worth also noting snow events on the GFS on Thursday, Saturday and Sunday for various parts of the country, not just N/W areas.

[Mucka]

41 minutes ago, Man With Beard said:

GEM also close to an easterly at T192.

Worth also noting snow events on the GFS on Thursday, Saturday and Sunday for various parts of the country, not just N/W areas.

Indeed. Just to put some meat on the bones of that as it is coming into range for rough guidance.

Thursday.

Good prospect of snow showers becoming prolonged and penetrating well inland from NW.

More sustained period of snow likely for parts of the Southwest.

 

Friday

Scattered snow showers

 

Saturday

Possible organised band of snow moving S/SE from shortwave trough. This one will be very hard to forecast because the boundary between rain and snow will be so fine and there is of course the chance the ppn won't be as significant as currently modeled. Seems quite likely we will be influenced by the shortwave/low moving SE or even sliding S down the ridge though. Could be anything from a big snow event to a damp squib depending on how it develops.

 

Sunday.

Possible widespread snow from Atlantic front.as it meets embedded cold air to the East. Again a very difficult forecast even nearer the time as Eastward progress cannot be known, could be so far West as to stay dry, too far East and be rain, somewhere in the middle and be snow. It is more or less rain on GFS 00z but very small improvements West and it would be snowy.

 

Edited January 10, 2017 by Mucka

[The PIT]

Interesting runs in FI as models GFS and UKMO swing towards ECM solution. A long way out so this idea could vanish in the next run.

[That ECM]

21 minutes ago, The PIT said:

Interesting runs in FI as models GFS and UKMO swing towards ECM solution. A long way out so this idea could vanish in the next run.

Looking at the fax charts and looking in particular at Italy you can see the low which will help the high from sinking. Now, how far north east it drifts will be interesting. Ukmo at T144 is very encouraging. Gfs has moved to this scenario but not as strongly. ECM to come but what will be of major interest to me will be the next fax charts. I would also suggest sticking with them for short term details as well. 

Edited January 10, 2017 by That ECM

[karlos1983]

What a sight.. when was the last time we saw a northerly like this? We must be talking years!!

Seems like forever, let's hope the other elusive winter gold shows its face again in the coming frames, 

Edited January 10, 2017 by karlos1983

[ArHu3]

2 minutes ago, karlos1983 said:

What a sight.. when was the last time we saw a northerly like this? We must be talking years!!

Seems like forever, let's hope the other elusive winter gold shows its face again in the coming frames, 

what are the chances of lake effect snow for the dutch west coast?

[karlos1983]

Just now, ArHu3 said:

what are the chances of lake effect snow for the dutch west coast?

I would say nailed on if the uppers are ok

[Cheshire Freeze]

ECM & UKMO virtually identical at 96...GFS less so. 120 ECM should tell us more...

EDIT: perhaps even a tad sharper than the UKMO, still very cold across the UK with -8 uppers relatively widespread

Edited January 10, 2017 by CreweCold

[That ECM]

4 minutes ago, CreweCold said:

ECM & UKMO virtually identical at 96...GFS less so. 120 ECM should tell us more...

It's stunning. Model viewing at its best.

Edited January 10, 2017 by That ECM

[karlos1983]

1 minute ago, That ECM said:

It's stunning.

Yes a corker 

heights building and cold air coming back in to the east. NICE!!

Edited January 10, 2017 by karlos1983

[knocker]

A general overview of the GFS/GEFS this morning is little changed from yesterday evening. What it still appears to boil down too is how it handles the details of the upper air pattern change upstream and then downstream staring around T 120 and finalizing around T264. In a nut shell this involves:  The vortex and trough over Alaska, massive WAA into N. North America which eradicates the Canadian vortex and amplification downstream over the Atlantic. It is the detail of the latter which is exercising some great minds. The 7-12 anomaly which is where we are this morning with the transition to a more westerly zonal regime almost complete.

So a little more detail from this morning's det run.  I'll leave the detail of the end of the week to the more dedicated threads suffice it just to post the 06 chart for Friday without comment.

Sunday 12z sees the amplification well under way with the Azores ridging north just to the west of the U and the next trough ejected from N. America which has phased with the energy still coming from the Canadian vortex at this time to form a new trough in the western Atlantic with links to the ubiquitous low pressure area to the south.

From this position it's all about distribution of energy best illustrated by the jet which is indicating the trough disruption in mid Atlantic whilst highlighting the huge amount of energy running east over the top which is in the act of suppressing the ridge.

This process continues until at T240 where this is the position. Ergo most of the UK will be under the influence of the high cell as it moves east, the NW being the exception as systems track NE, and it is here that parts of the UK may come under the influence of a continental flow  and some colder air which is situated further south and east. Obviously this all rather depends on the position of the surface high before the westerly regime kicks in so any definitive detail is not possible at this time.

Edited January 10, 2017 by knocker

[Cheshire Freeze]

GFS has us in a westerly at 120 

ECM and UKMO N'ly

Edited January 10, 2017 by CreweCold

[karlos1983]

144 the ecm is more amplified, this could be a stunner of a run 

Edited January 10, 2017 by karlos1983

[Ali1977]

Awesome ECM at 144, Easterly looking odds on later in the run and maybe far enough north to bring some proper cold and snow shower activity 

[Cheshire Freeze]

Just now, Ali1977 said:

Awesome ECM at 144, Easterly looking odds on later in the run and maybe far enough north to bring some proper cold and snow shower activity 

Oh my

Stays very cold for the majority too

[Mucka]

Just now, karlos1983 said:

144 the ecm is more amplified, this could be a stunner of a run 

It already is 

[karlos1983]

1 minute ago, Mucka said:

It already is 

Well yes, But you know what I mean mucka  lol 

my avatar picture would be nice 

Edited January 10, 2017 by karlos1983