Model Output Discussion 01/09/17

[knocker]

The ecm springs an upper trough out of the eastern seaboard Thursday 00 which has sufficient energy to run around/through the resurgent ridge to dump a nasty little surface low over the UK on Sunday (possible snow to NW ahead of the front?) Thereafter as it tracks into Poland the ridge reasserts itself but the damage has been done and the next low swats this aside and arrives on the scene late Tuesday bringing a fair whack of rain for most and sets the tone for some quite inclement weather for the UK by the end of the run dominated by low pressure. This becomes centred to the east and thus the surface wind veering northerly which could, if it actually materialized of course, initiate blizzard conditions in Scotland.

[Snowy L]

1 minute ago, Man With Beard said:

That disturbance at D9 has come straight off Greenland. How is it not colder?

Looks like the Atlantic shortwave morphed into it too.

[swfc]

5 minutes ago, Snowy L said:

Looks like the Atlantic shortwave morphed into it too.

Also Atlantic sst are above normal atm.that said the temps in greenland would suffice unless like you mention they have mixed out? 

[chris55]

1 hour ago, nick sussex said:

Its like a drama that never ends.

When does it ever lol (especially in the MOD)

Overall id say more than enough to keep the coldies (including me) interested. Inter run nuances aside (ops and ensemble suits) the overall longwave pattern forecast remains the best we have seen in November sine 2010. 

[carinthian]

A bone chilling day here in the Austrian Alps, lights on all day and temp never higher than -5c. Our snow forecasting model predicted 15cm, in fact we only got 7cm in our location but timing spot on. Our portal forecasting service predicting a particular cold week commencing 20th November with mod/heavy snowfall. This sort of ties in with ECM chart below at168t. Think this chart will be similar to what UKMO extended charts will showing and that's a NEly or possible later in the period a Easterly flow for most of the UK.

C

Edited November 13, 2017 by carinthian

[comet]

Quite positive output tonight from a coldies perspective. I do wonder though if the models are over milking these spoiler lows but if they do manage to scupper a significant cold spell with a very conducive AO and NAO then it really will be a great chance missed. I can only assume these mid Atlantic spin off lows are a result of the Atlantic sst profile. As I said before though fingers crossed the models are making a meal out of them.

[nick sussex]

Overall some possible interest moving forward but its one of those set ups that's finely balanced.

The ECM is actually more progressive with low pressure over the US at T168hrs but then salvages the situation by holding troughing over ne Canada and this shoots off a couple of shortwaves in towards the UK.

Theres not a great depth of cold though at this stage, its possible with a few tweaks northern areas in particular could see a shortwave run se into some colder air so a chance there for something wintry.

Indeed the one that pops up earlier at T144hrs could produce something on its northern flank, if its a shallow feature this would help and much depends on the track, currently it looks a bit too far north but a southwards correction could bring some interest to Scotland higher ground.

 

[bobbydog]

19 minutes ago, Man With Beard said:

That disturbance at D9 has come straight off Greenland. How is it not colder?

probably because it is plunging down into 'warmer' air and mixing out slightly. it is a fairly strong LP system. i would imagine, if it continued it would drag colder air down. anyway, its still only november so... chill.... 

[Summer Sun]

UKMO goes north westerly at t168

[Connor Bailey Degnan]

Ecm mean at Day 10!

[feb1991blizzard]

The EPS are absolutely dyer, if its Northern Blocking that you like anyway.

[karlos1983]

6 minutes ago, Connor Bailey Degnan said:

Ecm mean at Day 10!

Eeesh that’s junk!! gonna need the Thunderbirds to rescue this one. 

[bluearmy]

10 minutes ago, feb1991blizzard said:

The EPS are absolutely dyer, if its Northern Blocking that you like anyway.

Dire? A long way from dire and with the scandi low anomoly backing west a bit through week 2 the uppers are lower than the 00z run

[V for Very Cold]

13 minutes ago, Connor Bailey Degnan said:

Ecm mean at Day 10!

do we have the option to bin that one??????

[stainesbloke]

14 minutes ago, feb1991blizzard said:

The EPS are absolutely dyer, if its Northern Blocking that you like anyway.

Dire

[bobbydog]

9 minutes ago, feb1991blizzard said:

The EPS are absolutely dyer, if its Northern Blocking that you like anyway.

they can't be THAT bad...

 

 

[V for Very Cold]

oh bugger ...that's DWyer!

[karlos1983]

2 minutes ago, Heekster said:

Yes mild and going to become even milder by the look of that ! 

Are you on a wind up Heekster, ? Just genuinely curious. 

[V for Very Cold]

apologies  - back onto the models

[bluearmy]

The eps didn't quite make -3 and the ec op failed to reach -4 despite looking like it should 

[bluearmy]

Just now, Heekster said:

No just learning but would the Azores High not just move in from there, it's been a bad day on the models for sure.

You can't really extrapolate a mean chart like you can an individual run. Fwiw, the mean Azores ridge fails to get any further east than it is at day 10 and infact retrogresses somewhat 

[That ECM]

1 minute ago, Heekster said:

No just learning but would the Azores High not just move in from there, it's been a bad day on the models for sure.

How and why? Not being funny or argumentative. I am happy to view these so early in the season could be a lot worse.

[karlos1983]

11 minutes ago, Heekster said:

No just learning but would the Azores High not just move in from there, it's been a bad day on the models for sure.

Ok, in that case, sorry. 

Hard to tell really, but that’s not a a good looking mean imo.

must say I wasn’t expecting that after the ecm this evening.

Enjoy the learning! 

Edited November 13, 2017 by karlos1983

[ANYWEATHER]

Evening All, so a seasonal outlook in the next couple of days ,yes turning a bit milder but with it the problems given the time of year for southern Britain with mist and fog. It turns colder by the end of the week for all with cold winds for the north , and quieter settled conditions for southern Britain,as high pressure builds in allowing frost and fog again to be a feature...As we move to the ten day period show potential for Winter to begin from both gfs and ecm but of course at that range , lots of changes to come ,but the overall trend is for cold for the uk as we have a split vortex forecast...One thing for Coldies is there is not any real mild scenarios thrown up, certainly interesting viewing ...

[Singularity]

I expect differences in the timing of lows nipping across the UK, and the transient ridges in between, have greatly muted what would otherwise be a mid-Atlantic ridge and Scandinavian trough picture.

A little surprised to see the mean polar heights drop so much though. Perhaps a scattering of runs moving the potential deep Pacific-side low near or across the N. Pole? Members with greater ensemble access/time on their hands will know more.