The hunt for cold - Model discussion (late November)

[shaky]

6 minutes ago, northwestsnow said:

Not sure about that shaky..

UKMO/EC were both very nice this morning..

Yup forgot to add that this mornings runs seem to have broken that trend but its been happening a lot recently!maybe a data issue!!

[Tim Bland]

21 minutes ago, Stuie W said:

Tim, have a look at summers graph, nothing is an outlier post the 9th, anything possible.

Sorry Stuie but if it lies outside of the envelope of ensembles then is an ‘outlier’ , doesn’t mean it’s definitely wrong as the op is at the highest resolution 

[Stuie]

3 minutes ago, Summer Sun said:

UKMO extended looks to have the low in the Atlantic a bit closer to the UK and Ireland than ECM 

UKMO                                                               ECM

Let me try and get this right, I prefer the UKMO`s Low as it is elongated, heading NE and would not plough through any ridge.

[Stuie]

1 minute ago, Tim Bland said:

Sorry Stuie but if it lies outside of the envelope of ensembles then is an ‘outlier’ , doesn’t mean it’s definitely wrong as the op is at the highest resolution 

No need to apologise mate, overlooked, nice zooming.

[northwestsnow]

1 minute ago, Spah1 said:

I’d be interested in that day 10 ECM chart. Straight Easterlies don’t bring snow to West Lancashire generally.

It’s fun watching the chaos elsewhere but we only got a light dusting in March. 

A battleground scenario however would get me polishing the bulb in the back garden spotlight.

And 20miles to your east in the foothills of the penines it was waste deep in drifts...granted i have 600ft altitude to help but location wise my best wind direction is east or north east winds..

Onto UKMO, i actually prefer the ukmo 168, it suggests to me a lot of energy going into the southern arm..

[BlazeStorm]

Wish these model outputs would stop flirting with us... 

 

ECMWF looking promising though!

Edited December 3, 2018 by BlazeStorm

[northwestsnow]

Very happy with EC mean tonight...

And happier still Darren Brett is ramping up a big scandy anti cyclone next week..

[Frosty.]

Looking at tonight's Ecm 12z ensemble mean @ T+240 hours, it certainly ain't mild!!..let's hope the power of positive thinking can darken those shades of blue on subsequent runs!..nobody will be more delighted than me if we can get some entrenched cold..and hopefully SNOW in the run up to christmas!

[Seasonality]

37 minutes ago, Ben Lewis said:

It’s 9 days away. 

Pretty to look at but the timeframe to moan at. 

Bring it within 4 days then your post has some legs. 

Well I'll give you a hint about my post. It starts with a j, ends with an e and has an ok in the middle. But I'm assuming you knew that and you're being ironic.

[Scandinavian High.]

5 minutes ago, northwestsnow said:

Very happy with EC mean tonight...

And happier still Darren Brett is ramping up a big scandy anti cyclone next week..

Yes just seen bbc weather outlook going for Easterly winds it’s getting very interesting .

[tight isobar]

8 minutes ago, northwestsnow said:

Very happy with EC mean tonight...

And happier still Darren Brett is ramping up a big scandy anti cyclone next week..

Yep..the wrap is on-and forming.

And lets not forget the ramifications @overheads -strato-trop-...

Waving doing a fine job!

[snowray]

7 minutes ago, abbie123 said:

Yes just seen bbc weather outlook going for Easterly winds it’s getting very interesting .

OMG, really? Game on big time then!

[sorepaw1]

16 minutes ago, northwestsnow said:

Very happy with EC mean tonight...

And happier still Darren Brett is ramping up a big scandy anti cyclone next week..

I've just spat my strong Dutch lager out 

Darren Betts has said what the biggest mild

Ramper in history.

[Catacol]

OK - starting to get interesting now. Where are we on the shape of things to come? 

Fairly strong MJO has passed through the 8/1 orbit and looks set to reignite in the indian ocean into week 2

If you like looking at a few composites the phase 8 December weighting from the JMA looks a fairly decent fit for the pattern upcoming given lagged impact

And as this pushes on to phase 2

we see a signal for pressure rises to the east which then pull back west as the MJO enters the indian ocean once again.

I've come to realise that these composites are far from gospel, but we have perhaps a sense of the MJO forcing that will impact the pattern over the next 2 weeks.

Meanwhile we await the next pacific cycle to see how much AAM can be injected via torque or convection activity. It would appear that frictionals have now reengaged

and we await subsequent impact of mountain torque activity that will follow. I am hoping to see a spike in east Asian activity in particular that can extend the jet over the pacific and provide the momentum to encourage a more meridional pattern at 55-60 and further north. Given frictionals are now climbing we can expect to see this in the next 5 days or so.

Conclusion? MJO activity setting up the north atlantic pattern nicely for pressure rises first to the NW and then more particularly the NE.....and at just the right time we get an engagement of the pacific jet to help reinforce those eddies over the north atlantic still further. I see an easterly of sorts at mid month with an undercutting flow....perhaps then a relaxation into a more cold omega UK pattern towards month's end and then into early January another impact from the pacific. Where will the vortex be by then given the signal for the scandy high and ongoing north pacific low? Hopefully on its knees and ready to pop. Anyone like to take a guess at what would happen if a renewed MJO cycle through phase 7/8/1 were to combine with the next pacific cycle at just the time that the vortex comes under major stress? 

Homer would know what to say. Hmmmmmmmmm.

But a lot of water to flow under the bridge yet. Important that the MJO maintains decent amplitude over the medium term (and given the Nino background this is not a given by any means because in a Nino year the MJO is supposed to fade through winter....) and that we don't get a sudden solar spike. And vortex stress is not destined for sure to sit pretty for the kind of epic impact we got back in March either. A lot of macro and micro scale analysis lies ahead. But these are, in general, very good signals at present.

 

[Duane S.]

Nice charts, super nice charts. My concern is this though, and it is nothing to do particularly with the GFS...

NE block is an absolute cert. Great but I wonder if it is going to end up too far north, allowing undercuts with us on the wrong side. High pressure will then ridge up from the south. Still cool but no snow for the masses.. Perhaps the far North.

Not like me at all to be this cautious but I just feel this nowhere near a done deal. Now is not the time for a December 2012 style solar spike!

But... how brilliant is it we are in the game for an imminent decent cold spell on only the 3rd day of winter!? This is what winter chart viewing is all about!

And either way, absolutely stunning prospects later on. If the vortex thinks its struggling now, it has a nasty surprise coming its way in the next few weeks. We would have to consider ourselves very unlucky if we haven't had a good cold spell by the end of January

[Allseasons-Si]

There is some meat on the bones starting to apear(as in cold prospects)in some of the charts/models/graphs/anomoly's etc

lets have a wee gander:-

the latest outlook from cpc 6-10/8-14 day outlooks shows the Azures ridge develope into Scandi with trough extension in the atlantic with possible trough undercut on the 8-14 day

eps/gefs height anomoly's at day ten,the eps is a lot better in regards to the positioning of the height anomoly's over Scandi with lower height's on the southern flank of the high

De-built ens temps/dewpoints getting colder each day and the wind direction is starting to show more easterly members in there now

30/10hpa from jma although not significant at this stage but it's a start and will see how this progresses over the next few days

a recent tweet from Mr.Hugo

so at the moment,things are looking good for a cold snap/poss cold spell,i just hope that i do not have to wait too long before i get my ski's out

P.S. nice to have you back Karl/Frosty,you have been missed xxx

 

Edited December 3, 2018 by Allseasons-si

[ICE COLD]

@bluearmy are you coming off your fence yet ?? Or is it gonna be another 24 hours ? 

[bluearmy]

4 minutes ago, ICE COLD said:

@bluearmy are you coming off your fence yet ?? Or is it gonna be another 24 hours ? 

sorry ........ fell asleep .......did i miss anything .......

 

 

encouraged by the ec spreads from the 12z.

im currently a little nervous that we could see the ridge get way north and phasing occur further north as has been the case on a couple of gfs op runs recently ... after all, going back to the beasterly  from last winter and the cold pool from last month, both involved the low heights accelerating across the meridian east to west in a way not seen by the ops at day 10/9 but picked up by ecm around day 8/7. 

the dncroaching undercut has become the theme of the day .....that fits with many recent eps control runs and presents the largest risk/largest reward route to snow events  

the scandi ridge seems secure but how it affects the uk remains uncertain .... will certainly go cold but how cold and will it go snowy???

I’m afraid we’re gojng to have to wait another day or two to know for sure what theme the continental flow will take  - then we can begin to look for detail 

[gottolovethisweather]

2 hours ago, Daniel Smith said:

I’m ready to jump down off the fence and hopefully Bluearmy will be joining me!

I’m 60/40 deep cold into the UK next week. High pressure will build this weekend turning things colder, good support for high pressure to extend and build across Scandinavia thereafter. 

Lots to resolve before deep cold touches our shores, but we’re a step closer this evening. Fantastic day 8 GEFS mean. 

 

I'm willing to agree on your comment "High pressure will build this weekend turning things colder, good support for high pressure to extend and build across Scandinavia thereafter." As I mentioned last Monday, there was a growing consensus even then, that between the inter/intra-model runs, the GFS, in particular, wanted to bring in HP dominance around December 6th through to 10th or thereabouts. As for deep cold, we need the ECM D9 and D10 charts showing such scenarios to be there at D4 or D5 in my experience, which means by the end of this working week, we will KNOW whether SNOW is something worth shouting about, for the run-up to the middle of December. Winter proper appears to be lurking close-by.

Edited December 3, 2018 by gottolovethisweather

[Ice Day]

13 minutes ago, s4lancia said:

And either way, absolutely stunning prospects later on. If the vortex thinks its struggling now, it has a nasty surprise coming its way in the next few weeks. We would have to consider ourselves very unlucky if we haven't had a good cold spell by the end of January

 

And this is the important point, even if the next 7-10 days doesn't deliver what we're all after, the vortex is so distressed the window of opportunity is wider than usual.  We often require a couple of bites of the cherry to get the 'proper' cold in for the UK and this could be one of those times, however, I'm very confident that we're going to see something significant by early January.  Time will tell of course!

[BLAST FROM THE PAST]

19 minutes ago, ICE COLD said:

@bluearmy are you coming off your fence yet ?? Or is it gonna be another 24 hours ? 

I officially came off the fence on 13/10/18

 

BFTP

[northwestsnow]

Hope 18z smells the scandy flavoured coffee..

Feel much more confident with the been going for it.

[Met4Cast]

56 minutes ago, northwestsnow said:

Very happy with EC mean tonight...

And happier still Darren Brett is ramping up a big scandy anti cyclone next week..

Yeah..

A few days ago the BBC monthly was going for mild Westerlies all the way through, goes to show just how little attention BBC forecasts are worth now they’ve ditched the Met.

I’m hoping to see a backtrack on the GFS 18z tonight..

[I remember Atlantic 252]

56 minutes ago, Frosty. said:

Looking at tonight's Ecm 12z ensemble mean @ T+240 hours, it certainly ain't mild!!..let's hope the power of positive thinking can darken those shades of blue on subsequent runs!..nobody will be more delighted than me if we can get some entrenched cold..and hopefully SNOW in the run up to christmas!

Welcome back Frosty.!!!!!, models except GFS looking good, often happens though

[Allseasons-Si]

Looking forward to the ec46 later,will it play ball?

what time does it come out again?