Model output discussion - 7th January onwards

[weirpig]

Two charts to show the slight shift west  edit bloody Karlos

6z/0z

 

Edited January 16, 2019 by weirpig

[winterof79]

Ties in with expected colder than average next week troughing to or near s/w

Edited January 16, 2019 by winterof79

[SLEETY]

gfs going back the other way now,so inconsistent it’s hardly wither bothering with after 120 hours 

[mountain shadow]

11 minutes ago, Man With Beard said:

ECM ensembles seeing D10 as a brief milder uptick - upper air mean temperature soon goes back to between minus 5 and minus 6

It's all getting a bit wobbly now - it's all variations around a cold theme, but I'm expecting some minor ups and downs before getting into the "reliable" 

Hi Man With Beard

Quick question if you don't mind.

Did the large EAMT not do anything then? Or are we still waiting for its impact?

[knocker]

9 minutes ago, Nick F said:

I used to think that the amplifying and de-amplifying upper troughs and ridges moving around the northern hemisphere are the key ingredient to implications for downstream patterns, but having read numerous US forecasts, partly though interest and also because I go storm chasing there occasionally, there is a lot of reference to how deepening lows over central and eastern the USA, which contain a lot of energy when they interact with gulf of Mexico moisture, can affect the amplitude and shape of upper troughs too, which obviously has implications to wave length and amplitude downstream across the Atlantic. So yes, agree that generally lows tend to follow the 500mb contour, but the lows aren't just purely led by mid-level flow, they are linked in and affect from bottom up to the mid-level flow too, the deeper the low the more N of E the low goes and that can affect the amplitude and shape of the upper trough. This is the issue with the winter storm going along the eastern seaboard next week, deeper it is, the more N of E it will go in track and more likely that the Atlantic ridge may be able to push north towards Greenland - rather than flatter flow of the 00z with the shallower system moving NE.

There is a split stream over the USA, the northern stream digs south in response to Hudson Bay PV dropping south, the northern stream brings south arctic front and interacts with southern stream moisture pulling in from GoM and spawns a low over the Plains of USA later this week, this low then deepens as it moves towards eastern seaboard, uncertainty over whether it will track inland or along coast and how deep. This low then moves NE towards Greenland, it's intensity and track important for low separation around Iceland towards UK next week, as the flow amplifies over the Atlantic downstream of the amplifying east US trough and winter storm. 

Thanks for that Nick and not forgetting the current SST anomalies along the eastern seaboard to throw into the mix

[SLEETY]

back to easterly again from a westerly 6 hours earlier,great consistency gfs

[winterof79]

No matter how hard the modelling tries it will not shake of the inevitable troughing and Easterly feed.

It just keeps coming back

[Man With Beard]

4 minutes ago, mountain shadow said:

Hi Man With Beard

Quick question if you don't mind.

Did the large EAMT not do anything then? Or are we still waiting for its impact?

I don't know I'm afraid - anyone else care to answer? 

[tight isobar]

11 hours ago, tight isobar said:

When viewing the GFS nxt 7 days..heres ya friend..

And the models foe!!.

Should see some elevated top dynamics..as ec..

Through the route!!

 

11 hours ago, tight isobar said:

When viewing the GFS nxt 7 days..heres ya friend..

And the models foe!!.

Should see some elevated top dynamics..as ec..

Through the route!!

Large lobe under increased pressure.

Tbh-im still more than happy going forwards...cross suites.

 

[Man With Beard]

Just one more point on the morning's runs - an active Atlantic may not be a bad thing if mountains of snow is what you're after - slight guesswork, but seems to me any incoming lows will be likely to disrupt as the reach the UK? 

[Lampostwatcher]

Gfs back to being a good run 6z

[Polar Maritime]

The Atlantic certainly looking more blocked, With stronger Heights pushing North leaving us in more of a Continental flow..

[winterof79]

12 minutes ago, Man With Beard said:

Just one more point on the morning's runs - an active Atlantic may not be a bad thing if mountains of snow is what you're after - slight guesswork, but seems to me any incoming lows will be likely to disrupt as the reach the UK? 

Yes I would guess the " Snow anywhere" may make a reappearance

[IDO]

From my simple dynamic analysis, it appears that the long wave pattern may be pushing the pattern away from Atlantic HLB'ing.

Up to about D7 we have forcing from the Atlantic able to make progress to a ridge. The PV having room to breathe. With the inception of the Pacific Heights, the PV becomes more confined and able to resist further Atlantic ridging on this run. I had assumed with the previous PV killing runs that we would be getting some help from the SSW downwelling. However, that may have been pre-emptive.

In theory, we are back to square one at around D10 with the Canadian PV lobe being eased NW to SE as the Euro trough acts as a conduit. Hopefully, the next shot will be better for a more blocked FI?

 

[karlos1983]

13 hours ago, bluearmy said:

A look at the mean heights day 16 ....geps, gefs, eps

    

 

should keep the interest going ......

incidentally @catcol, you may need to revisit your strat charts in the morning .....they will be rather different than they have been - both ec runs consistent today ........

 

13 hours ago, bluearmy said:

 

Here’s your day 9 50hpa to compare with yesterday’s day 10 you posted 

 

13 hours ago, bluearmy said:

And 30hpa .... gfs op latest runs have also shifted this way though the ridge placement bit further east than ec

How's this looking today Nick?

TIA

[Chris101]

Fwiw i think we are still in a good position to see the next ridge do slightly better than the first, the canadian lobe will drain and become more malleable each time we slide a piece off, fairly confident of a ridge sticking by Feb.

Bit like when you used to flick soggy paper at the classroom ceiling, there was always one that got stuck up there for days.

[frosty ground]

18 minutes ago, Man With Beard said:

Just one more point on the morning's runs - an active Atlantic may not be a bad thing if mountains of snow is what you're after - slight guesswork, but seems to me any incoming lows will be likely to disrupt as the reach the UK? 

The 06z Run plays with idea twice after next weeks attempt (chart as an example)

If this is how the next few weeks play out we could have pretty much any type of weather from mild southerlies to cold easterlies and even cold north westerlies but with lots of moisture.

Each event would be down to the wire forecasting as well

Edited January 16, 2019 by frosty ground

[Frosty.]

The Ecm 00z ensemble mean looks pretty cold throughout, some days colder than others but nothing I would call mild is on the horizon!..there should be at least some wintry ppn at times and overnight frosts / icy patches.

[Lincs Observation]

4 minutes ago, Frosty. said:

The Ecm 00z ensemble mean looks pretty cold throughout, some days colder than others but nothing I would call mild is on the horizon!..there should be at least some wintry ppn at times and overnight frosts / icy patches.

A suprisingly low key summery frosty, not sure if i should be worried that for all of the bluster on here in the last few days that you may see things a little differently?

LO

[ArHu3]

43 minutes ago, karlos1983 said:

that's yesterday's I'm afraid

Still ok,but not as jaw dropping

Stupid browser cache

[Fozfoster]

Para 06Z for the weekend..

[Methuselah]

Not a mild run, but not an overly cold one, either: 

Still nothing that one could definitively say looks much like a manifestation of the background signals...

[weirpig]

Control  run.  Can quite clearly see the difference at 120hrs  with the storm forming in the USA  much further west    Alot of the  ensembles are taking a different route with this storm  very different solutions being played out.

the third picture brings a easterly in at 144hrs

Edited January 16, 2019 by weirpig

[IDO]

Within the long wave pattern if we can get favourable mesoscale movements, from wedges to upstream forcing from the US storm to better phasing then we could benefit in the medium term from a colder outlook.

FI starts early still and at T156 we can see the GEFS exploring that PV chunks movement around the UK.

 At T174>> 

Plenty of better options, in fact, a higher proportion than the op, so upgrades certainly possible within the bigger picture. Though the Control also a bit flat.

[karlos1983]

Not much wrong with these