Model Output Discussion 01/09/17

[northwestsnow]

Are we seeing where the METO are coming from with their outlook?

oooer matron

Edited November 11, 2017 by northwestsnow

[Man With Beard]

If the Atlantic trough makes it to the NW Europe trough quickly, this could get very tasty - heights locked in to the North West.

[karlos1983]

That’s rather tasty 

[mpkio2]

3 minutes ago, karyo said:

The long road to cold should always be avoided unless it is the only road. The longer it takes the more things can go wrong.

The 12z GFS doesn't go the UKMO route. It has a weaker Atlantic block than the 6z but somehow the northwesterly at the end of next week delivers colder uppers to the UK.

 

Yeah, I completely agree with you.

It's a route we (Coldies!) don't want to take if need be. GFS/ECM route is much easier, I think.

Also, speaking of UKMO, it's ditched it's 06z pattern!

12z UKMO 11/11 t144:

Looking very much like the 12z GFS!

12z GFS 11/11 t144:

[feb1991blizzard]

UKMO still nowhere near as good as the GFS but its a trend towards it, the GFS is a stonker, the Atlantic ridge needs to be more defined on the UKMO.

[northwestsnow]

Well one things for sure- ukmo has had an early (or late) season fail- it was miles out with its previous runs.

GFS brings the threat of snow showers into NW England over the weekend- again altitude will play a part, a big part ..

[Mucka]

We are beginning to see some consistency in the models for the mid term now with GFS and UKMO moving toward ECM type solution.

UKMO has been quite irratic actually and is probably still playing catchup.

We can now be fairly confident of a trough digging down from the NW to affect the UK around the 17th with a colder polar flow being introduced as it digs SE.

The detail of how sharp this pattern will be is as yet undecided with UKMO having the flatter pattern and GFS the sharper.

 

Naturally the sharper pattern is preferable for bringing in polar air rather than polar maritime but also for further amplification as we progress into last 3rd of Nov.

I would expect ECM to back GFS rather than UKMO this evening given its recent output and that UKMO inconsistency. (I'm not discounting UKMO or saying it is poor for coldies, just GFS is my preference)

If we go with recent ECM and GFS output we can expect wintry showers to feed in from NW Britain Friday afternoon  with wintry showers getting to lower levels and pushing further SE through next weekend.

 All that should be fairly nailed on now with an Atlantic block established next week and UK hopefully on the cold side of the trough rather than under it.

thereafter alignment of the trough and upstream amplification will be all important.

We want to see a negatively tilted trough digging into Central Europe with any Scandi ridge building N/NW if possible and joining with arctic high.

This will aid blocking upstream and also likely be a prelude to a continental flow (Easterly) setting up but if we want to bring in cold uppers we will need the trough to dig deep into Europe rather than stall out and fill over Scandinavia - at least for any clean progression.

If the trough stalls out further NE then there is a danger of any Atlantic trough phasing with it and breaking down the blocking pattern or at least cutting off any potential cold flow, but that is all in FI and idle speculation.

We could also get any Atlantic trough disrupting against the Atlantic block and being pushed further South which could mean any phasing of Atlantic air would be mixed in with polar air. In winter proper that would be a perfect set up for frontal snow of course.

Back to reality though, and let's see how sharp we can get the pattern in the mid term and how cold any upper air will be.

 

Edited November 11, 2017 by Mucka

[karyo]

2 minutes ago, mpkio2 said:

 

Also, speaking of UKMO, it's ditched it's 06z pattern!

12z UKMO 11/11 t144:
 

Looking very much like the 12z GFS!

12z GFS 11/11 t144:

I can't complain with the 12z output so far, it is looking good and I will be in Cumbria next weekend. 

[mpkio2]

I don't usually ramp, but...

12z GFS 11/11 t216:

Man, that is a STONKER!!!! 

One solution out of many and all for fun at this stage, of course!

[Frosty.]

I very much like what I'm seeing here, next weekend looks colder than this one with frosty nights and even some snow around! 

An early taste of winter on the Gfs 12z..Bring it on i say.  much better than mild swly  mush?? get the cold air in place first?

[northwestsnow]

Looks a very cold run for Northern Britain in particular with frost and ice becoming frequent with the chance of snow showers for some places- much as the meto forecast.

Very nice.

[snowray]

Worth a ramp....Rain, sleet and snow moving slowly South...Bank!

[Singularity]

Trough tilting very negative and disrupting with a secondary low running into the base of the trough by the UK... this is what I put forward a few days ago as the most realistic way forward based on past examples. Not only provides some wintry chances but allows ridging to remain to the NW rather than sink to the W, and the new import to Europe 'props up' that ridge even as it comes under pressure on the NW flank.

The better blocking to the NE by day 10 is of course a potential bonus, but it seems a lot of luck will be needed for that to align in a nice way for us to work with. 

With the polar vortex stirring, this Azores-Scandi type 'hang-back' of cold air looks to be about as good as we can manage from what the GFS 12z offers. 

Given the changes in the 8-10 day range, though, things could yet end up quite a bit different!

[snowray]

Quite a snowy run as we enter the last 1/3rd of November, even to lower ground I would expect.

[knocker]

Pictures speak louder than words

[Dorsetbred]

31 minutes ago, Mucka said:

We are beginning to see some consistency in the models for the mid term now with GFS and UKMO moving toward ECM type solution.

UKMO has been quite irratic actually and is probably still playing catchup.

The detail of how sharp this pattern will be is as yet undecided with UKMO having the flatter pattern and GFS the sharper.

I always seem to think that the UKMO, is the "Old Man" in the team, calculating, careful and not open to daring...

It considers all options, whilst being wrong (on occasions) it's generally very cautious, as these forecasts demonstrate.

 

[feb1991blizzard]

4 minutes ago, knocker said:

Pictures speak louder than words

Indeed they do old boy!!!

[knocker]

What's with this old boy crap?

[northwestsnow]

3 minutes ago, feb1991blizzard said:

Indeed they do old boy!!!

Yes Feb- we could see some wintry suprises as we head through next weekend- esp Isle of sky road/ top of Ripponden road etc- 

ukmo tho nowhere near as good as gfs- could be playing catch up, EC will be interesting this evening!

[johnholmes]

2 minutes ago, knocker said:

What's with this old boy crap?

look in the mirror laddie!

[knocker]

1 minute ago, johnholmes said:

look in the mirror laddie!

Oh I don't have a problem with that old man but I do with being patronized

[Met4Cast]

Lots to be excited about tonight old boy. Even the old boy UKMO is getting in on the action trending towards the GFS and ECM this evening, not a full swing towards it but every little helps old boy. 

Haven't looked at the charts for a couple of days but the old boys known as the GFS ensembles have trended cooler again in the extended with quite a few members bringing that -5c isotherm over the UK now. 

Old boys will know that the GFS tends to underplay the cold air until closer to the time. 

[Ali1977]

Don't think it was meant that way knocker...Model wise, things are looking great for coldies, altitude and night time fronts surely a major factor mid Nov for lying snow, if indeed these charts keep going.

[NeilN]

It's promising to say the least. I'd rather get the cold in,and build on snow for DJF. 

[Paul]

Can we get back on topic please.