Model Output Discussion - 18z 31/10/15 onwards

[Summer Sun]

T192 getting colder as the north to north westerly flow continues to push the colder air further south

 

 

Edited November 13, 2015 by Summer Sun

[joggs]

We just need that high in the Atlantic to slice up to Greenland

[Cloud 10]

ECM being very naughty this evening,surely not a Greenland/Siberian HP link coming?

 

 

edit..

 

Anomalies anyone?

 

Edited November 13, 2015 by Cloud 10

[Summer Sun]

It could feel raw down the east coast later next week with a strong north to north easterly wind

 

 

The cold air remains in place

 

[Allseasons-Si]

That is watering my eyes

 

 

 

[joggs]

ECM being very naughty this evening,surely not a Greenland/Siberian HP link coming?

 

 

edit..

 

Anomalies anyone?

 

ECH101-192.GIF.png

A thing of beauty lol.I'm not on board until the meto show flickers in their ext outlook.

[Mucka]

ECM being very naughty this evening,surely not a Greenland/Siberian HP link coming?

 

 

edit..

 

Anomalies anyone?

 

ECH101-192.GIF.png

 

It is indeed. Pretty much showing the best case scenario tonight whereas JMA shows what can go wrong even when building heights across greenland.

That said, given the balance of output, GFS fast n flat seems the least likely so that is something to grab on to.

 

All eyes on tonight's ECM ensembles for a downward trend in temp.

Edited November 13, 2015 by Mucka

[SMU]

Evening All

5 posts in 24 hours - something must be a foot....

The ECM / GEM combo tonight are almost worthy or 'boom' runs - with the ECM at 192 having developed a fully cut off Greenland high-

The development of this projected cold spell is unusual in as much as it started out on the ECM at 240 as nothing more than a 24-48 hour toppler & has developed over the last 3 days ( 6 runs ) into something more significant with the main ground work at T120 -144

The only caveat is The GFS is not on board yet ( although playing catch up ) so because of that we have to wait another 24-48 hours ....

However onto the upbeat bits - my commentary on this is noone has forecast this - all agencies going with the el nino climatology / analogues which suggest totally the inverse at this early entry point to winter-

Chart of the day -

With the -6c line getting into central southern england & snow showers in the north / North east.

The key chart though is the 120 one with that significant plume of WAA into canada ( having commented on this over the last 36 hours )

This is about as good as it gets !!

Have a good eve-

S

Edited November 13, 2015 by Steve Murr

[Mucka]

LOL why not finish with snow giving channel low?

 

[Summer Sun]

Here comes the easterly and channel low!

 

 

Edited November 13, 2015 by Summer Sun

[lorenzo]

Always great to see the black hole anomalies come flying out of the ECM, agree that the 120 pulse on 850hPa temps is key to this. 

 

Pretty amazing ECM, not just for the Greenland evolution, that Siberian high is turning into something of a monster.

[Ali1977]

It would be very interesting to hear if this ECM has any backing from the METO. That ECM would have the potential to produce a long very wintery spell with UK wide ice days and snow.

[gottolovethisweather]

ECM being very naughty this evening,surely not a Greenland/Siberian HP link coming?

 

 

edit..

 

Anomalies anyone?

 

ECH101-192.GIF.png

 

2010 reasons to think it might happen but 2010 reasons why it might not, anyway that's enough about 2010, there's about 201.0 hours to go before such charts come to fruition.   Might see things go BOOM in here should these charts still be there come the forthcoming Monday/Tuesday as they'll be well within the reliable by then and therefore likely to verify to one degree or another. I await the weekend wobbles within the various Model suites in the meanwhile and wait with bated breath to see whether the media/MetO/BBC start ramping up the potential too. Some fascinating discussion to come whatever the outcome.   As mentioned previously, a lot of newsworthy nasty weather types around well before the potential for an initial burst of proper polar air infiltrates our shores. 

Edited November 13, 2015 by gottolovethisweather

[radiohead]

A cracking ECMWF run tonight. And promising GEM, NAVGEM and UKMO runs too. I do hope the ECM isn't overdoing the amplifiication as we've seen the model do this several times in the last couple of years. Either way, some fun model watching ahead once again!

Edited November 13, 2015 by radiohead

[Man With Beard]

ECM finally gets round to its favourite pastime, the overly blown-up Greenland High in the D6-D10 range which, from around this time of year onwards, causes a minor meltdown on this forum. The Greenland High is the most perilous pattern change to achieve, 9 out of 10 subtle variations in the weather models seem to erase it as soon as it appears, so it as yet remains the outsider by a long way for me. 

 

But it is beautiful, so HERE IT IS!!!!
 

 

Incidentally, I notice the GEFS has a whole range of beauties such as this:

 

[Cheshire Freeze]

It would be very interesting to hear if this ECM has any backing from the METO. That ECM would have the potential to produce a long very wintery spell with UK wide ice days and snow.

 

I'll go one further- the ECM run is the best opening to winter charts we've seen since 2010. Locked in wintry pattern shown post 168 hours. As Steve M has said that's a 'boom' if it could get to day 5.

Edited November 13, 2015 by CreweCold

[chris55]

The last few days of model runs have perked my attention lols, and tonight's ECM det is worthy of a post!!

 

The wheels are set in motion by 144

 

 

And by 240 something more "solid" is afoot!!

 

 

All in all (although to far out to be taken entirely at face value) things are edging in the right direction for anyone into their colder set ups!

[Cheshire Freeze]

The last few days of model runs have perked my attention lols, and tonight's ECM det is worthy of a post!!

 

The wheels are set in motion by 144

 

 

And by 240 something more "solid" is afoot!!

 

 

All in all (although to far out to be taken entirely at face value) things are edging in the right direction for anyone into their colder set ups!

 

Get a Siberian-Greenland high link up and you're into '62-'63 territory.....we can dream eh 

[bryan629]

This place may start to get busier over the next day or so if this still shows tomorrow - Where's knocker and his daffs?

Knockers in the woodshed wondering whats lurking in there... oh look an arctic plume

 

[phil nw.]

Yes the ECM is a cold run alright and if verified would bring some freezing days up north.

There is a but and that is the differences with the amount of ridging off the E.Seaboard as early as day 5, which soon becomes stark as the run goes on with the ECM showing a Greenland high at the end.

We shouldn't have to wait too long before this is resolved as this difference is quite early on.

 

I think even if the pattern turns out less amplified there is enough ridging in the wavelengths to bring that polar air south towards next weekend.

 

A look at the UKMO chart at T144hrs

 

a middle ground between the other 2 which is good enough reference point very often.

 

It does look like around next weekend is the landing point for the coldest air to arrive and this had been well pointed to in recent GFS 2m ens graphs.

First apparent on the 6/11 and followed up through the following days.the 2nd graph was issued on 11/11 and the 3rd one is this evenings output.

 

Of course further north it will be even colder based on those.

So yes a change to colder conditions is still on but we just need to see those differences in the Op runs resolved wrt the amplification upstream from day 5.This of course would influence how cold it could get,especially further south.

 

[Liam J]

Meanwhile in the more reliable time frame and of great concern, some parts of the UK are looking at the likelihood of significant flooding issues over the weekend and into next week, the NetWx hi-res rainfall totals paint a very grim picture.  

 

 

Potential for another storm in the north on Monday, although not as strong as Abigail but the impacts could be more widely felt.  

 

 

The risk of further rainfall throughout next week which will just exacerbate any flooding issues.

 

Edited November 13, 2015 by *Sub*Zero*

[Cheshire Freeze]

ECM ensembles will be very very interesting tonight- solid support at day 6 and it's over to the GFS. I'd love to see a flip from the GFS on the 18z to support the likes of the GEM and ECM but that's probably hoping for too much. Still, any move towards those models by the GFS would see feedback mechanisms take over anyway I suspect- the upshot of this being it'd probably get there eventually but maybe not as quick as the ECM tonight. We await with interest...

[phil nw.]

I have moved a couple of posts with no model discussion to the ramp thread

https://forum.netweather.tv/topic/83902-model-banter-moans-and-ramps-autumnwinter-201516/page-33

 

so just a reminder to keep on topic and please use the ramp thread if you feel your post is more suitable there.

 

Thanks all.

[Bristawl Si]

Not wanting to dampen the building excitement on here but i couldnt help noticing the big fat HP centred over Iberia shown in those charts posted by Phil.

That could be a foe for the South, in coming weeks if it does not shift v much.

[nick sussex]

ECM delivers an early Christmas cracker for cold lovers but we have been here before with it over recent winters so I can understand the suspicion that this will be another let down.

 

At this point I'd back its view at least in terms of the phasing/timing upstream over the central USA. This does have good support from the other models bar the GFS.

 

For the GFS to be right then the ECM/UKMO/GEM/JMA would all have to be wrong at T144hrs, indeed even at T120hrs the others are already beginning to phase the north/southern jet streams and the GFS isn't interested.

 

The changeover to cold is not as simple as it could be because of the long train of low heights which runs sw/ne, you'll note that as the upstream flow amplifies one parcel of energy gets separated and runs sw. You're not dealing with a simple flow amplifies upstream ridge builds into Greenland clean northerly scenario, these parcels of low heights like the UKMO has at T144hrs over sw Greenland are still complications.

 

Its for this reason that I'd urge some caution in viewing the ECM's later output, the JMA solution shows how things could get more complicated. If things turn out more like the JMA then you can still get to cold as long as you get trough disruption from that Atlantic low this then can sever the connection between the Euro high and the high over Greenland.

 

So I think we need a few more runs and agreement upstream and a better idea of how the models will handle those complications before getting too excited about tonights ECM.