Model Output Discussion - Into Winter

[Severe Siberian icy blast]

17 minutes ago, Ali1977 said:

ECM Control Sunday , same as the op 

Interesting indeed

[ScottSnow]

3 minutes ago, northwestsnow said:

MJO latest..

 

What does that show ? I don’t know how to interpret it.

[Mcconnor8]

3 minutes ago, Ali1977 said:

I really didn’t know that thanks  

Since the ECM was upgraded in Summer so that the full ensemble pack runs at the same resolution as the Operational it essentially means that the Control will match the Operational as it begins with the same starting atmospheric conditions, whereas the rest of the ensemble pack begins with slightly different conditions. Does mean that we basically do get the ECM operational running to 360 hours now like the other models if we watch the Control instead.

Extended-range forecasts to be recast in next model upgrade | ECMWF

WWW.ECMWF.INT

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In the next upgrade of ECMWF’s Integrated Forecasting System, extended-range forecasts will have 101 instead of 51 ensemble members and will run more frequently than before, at a consistent...

 

[Cambrian]

12z ECM op days 5-10 shows the potential outcome of maintaining such strong northern blocking for such a sustained period. 

Keep your eyes on that little bubble of heights over the southeastern United States at day 5. Moves up through Newfoundland by day 8 then out over the Atlantic to meet the northern block at day 10. It’s actually quite a mobile setup - for the ridges! There is continual interaction with and feeding off the heights to the north. 

The same wave of heights can be seen crossing the Atlantic on the 500 mb / MSLP chart, breaks through the upper trough hanging down over the western Atlantic, forming a surface high and pushing the cut-off low so far south it ends up south of the Azores. 

This pumps up further heights into the forming high, and another wave of amplification heading up to our northwest towards Scandinavia.

In terms of the likelihood of something similar verifying, it’s probably not so much about particular pockets of heights and where they emerge on this specific run, perhaps rather that it’s symptomatic - in that the dice are so loaded from the outset by the northern blocking in favour of ultimately providing an evolution towards this type of outcome. 

[northwestsnow]

1 minute ago, ScottSnow said:

What does that show ? I don’t know how to interpret it.

Just putting it out there

In my world it shows a  mid Atlantic ridge to Greenland

[nick sussex]

17 minutes ago, bluearmy said:

Ali, you do realise that the op and control are the same ?  The control can begin to diverge somewhat as the runs progress because of the inherent chaos that exists in atmospheric modelling. However, before day 7/8 is v unusual and usually it’s only noticeable after T200

this idiosyncrasy only exists with current ec suite 

@SylvainTV any thoughts whether you could have the ec control as a stand-alone option on the left hand run list as it’s by far the best 15 day output we have access to ?

 

I’m confused ! 

I thought the ECM op and control have the same starting conditions and just that the op is higher resolution .

Whats specific to the ECM . 

PS I see Mcconnor 8 has put up that article . So that explains it . 

Edited November 27, 2023 by nick sussex

[Catacol]

5 minutes ago, ScottSnow said:

What does that show ? I don’t know how to interpret it.

Next pacific wave heading towards the dateline mid month. MJO forecasts currently range from ECM which has a very low amplitude progression to the BOMM which is high amplitude. I’m keeping a very close eye. We need the MJO to kick in properly so that the starter we are taking in this week has some kind of main course to follow later in December and into January. If ECM has it right at present then it doesn’t look great… but I’m pretty confident it is under modelling wave progression. Let’s hope the Aussies are good at what happens on their own doorstep! 

Current BOMM forecast 

 

Edited November 27, 2023 by Catacol

[Northwest NI]

1 hour ago, Jeremy Shockey said:

quite a spread in the ensembles

Ghee, I nearly didn’t get that joke!

[Uncertainty]

1 minute ago, Catacol said:

Next pacific wave heading towards the dateline mid month. MJO forecasts currently range from ECM which has a very low amplitude progression to the BOMM which is high amplitude. I’m keeping a very close eye. We need the MJO to kick in properly so that the starter we are taking in this week has some kind of main course to follow later in December and into January. If ECM has it right at present then it doesn’t look great… but I’m pretty confident it is under modelling wave progression. Let’s hope the Aussies are good at what happens in their own doorstep! 

Current BOMM forecast 

 

Let’s hope the 46 has gone this wrong… it shows zonal oblivion right out into Jan!

Tbf, it completely missed the current spell so not going to give it too much credence but as you say it stresses the importance of getting the next wave at decent amp…

[bluearmy]

1 minute ago, nick sussex said:

I’m confused ! 

I thought the ECM op and control have the same starting conditions and just that the op is higher resolution .

Whats specific to the ECM . 

Not since the eps upgrade early in the summer nick

the eps are now running at the same resolution as the op (9km) and at the same 137 vertical levels 

essentially the op is now redundant- it’s only because it comes out an hour earlier that it’s used!  I would assume that unless ecm are intending upgrading the op, it would make sense to not bother running it from a cost perspective. 

[Ali1977]

1 minute ago, Catacol said:

Next pacific wave heading towards the dateline mid month. MJO forecasts currently range from ECM which has a very low amplitude progression to the BOMM which is high amplitude. I’m keeping a very close eye. We need the MJO to kick in properly so that the starter we are taking in this week has some kind of main course to follow later in December and into January. If ECM has it right at present then it doesn’t look great… but I’m pretty confident it is under modelling wave progression. Let’s hope the Aussies are good at what happens in their own doorstep! 

Current BOMM forecast 

 

Fair one that BOMM is a belter - and surely lead to something much colder at the perfect time of year for severity - I can’t remember the last time we had a late December into New Year prolonged freeze - I mean I’m too young for 1962/63 but it would do ️

[SollyOlly]

1 minute ago, Northwest NI said:

Ghee, I nearly didn’t get that joke!

Oh, now that is a good one...!!

[MATTWOLVES 3]

I've seen enough of the ec 12z ens to say we remain in the game beyond day 7 or 8...theres some crackers amongst them and the PV remains in a confused state.

Thats me signing off as I'm neglecting my caring duties

Time to put ya feet up lads and lasses and blow the froff off a couple

[Downburst]

That chart is the tropics. So we want the MJO to get its MOJO back and get into some amplification as it moves through phases. 8 to 1 in December and moving fast to get there it

 

Edited November 27, 2023 by Downburst

[Ali1977]

Fax chart for Thurs /Fri - is this suggesting the low is little closer to the U.K. than the ECM is showing? 

Edited November 27, 2023 by Ali1977

[Thunder Snow]

I wouldn't rule out a few surprises towards the end of the week, I did very well from the beast from the east in 2018. I got quite lucky and the snow piled up

[Catacol]

6 minutes ago, Uncertainty said:

Let’s hope the 46 has gone this wrong… it shows zonal oblivion right out into Jan!

Tbf, it completely missed the current spell so not going to give it too much credence but as you say it stresses the importance of getting the next wave at decent amp…

Has to be a possibility, but anecdotally I have not been impressed by ECM modelling of the MJO in the past. Fair to say the MJO activity will not be the only player going forward, and I am wondering quite how important Atlantic SSTs might be at the moment in helping sustain a pattern that really ought to be fading faster than it is being modelled to, but for our sector in 3 weeks time the MJO combined with a rise in AAM will be very important I think.

[Notty]

8 minutes ago, Ali1977 said:

Fax chart for Thurs /Fri - is this suggesting the low is little closer to the U.K. than the ECM is showing? 

Interesting

Those low pressures don’t always head into France. Imagine trying to model where a spinning top will go - then change it for a puff of spinning air. Amazing how we get anything of use from the NWP. Anyway, anything is possible in the next week …

[Severe Siberian icy blast]

26 minutes ago, Cambrian said:

12z ECM op days 5-10 shows the potential outcome of maintaining such strong northern blocking for such a sustained period. 

Keep your eyes on that little bubble of heights over the southeastern United States at day 5. Moves up through Newfoundland by day 8 then out over the Atlantic to meet the northern block at day 10. It’s actually quite a mobile setup - for the ridges! There is continual interaction with and feeding off the heights to the north. 

The same wave of heights can be seen crossing the Atlantic on the 500 mb / MSLP chart, breaks through the upper trough hanging down over the western Atlantic, forming a surface high and pushing the cut-off low so far south it ends up south of the Azores. 

This pumps up further heights into the forming high, and another wave of amplification heading up to our northwest towards Scandinavia.

In terms of the likelihood of something similar verifying, it’s probably not so much about particular pockets of heights and where they emerge on this specific run, perhaps rather that it’s symptomatic - in that the dice are so loaded from the outset by the northern blocking in favour of ultimately providing an evolution towards this type of outcome. 

Yes you can see the wave interaction with the polar high pressure areas and how it strengthens them, i think as it moves way across the NH its going to interact with Siberia and produce a scandi, not saying we will get in on the action but high pressure to the north is the rule of thumb atm and the effects this can have moving forward is interesting to say the least! Most interested i've been in years! 

Edited November 27, 2023 by Severe Siberian icy blast

[Ali1977]

Well, the Icon moves the low back north again not a lot though 

[PiscesStar]

Just want to say how much I enjoy lurking in here and netweather members are a nice bunch. Thanks for making me feel so welcome   I'm still learning about how it all works!! It's very addictive 

Edited November 27, 2023 by PiscesStar

[Downburst]

5 minutes ago, Severe Siberian icy blast said:

Yes you can see the wave interaction with the polar high pressure areas and how it strengthens them, i think as it moves way across the NH its going to interact with Siberia and produce a scandi, not saying we will get in on the action but high pressure to the north is the rule of thumb atm and the effects this can have moving forward is interesting to say the least! Most interested in years 

This current setup is very much a disrupted Polar Vortex. As long as it's disrupted we are in the game. No question about it.

[Severe Siberian icy blast]

2 minutes ago, Downburst said:

This current setup is very much a disrupted Polar Vortex. As long as it's disrupted we are in the game. No question about it.

Exactly its alot like my friday nights walk home, lost, confused and looking for someone to warm me up

[MAF]

36 minutes ago, Northwest NI said:

Ghee, I nearly didn’t get that joke!

Can you CLARIFY that

[Downburst]

3 minutes ago, Severe Siberian icy blast said:

Exactly its alot like my friday nights walk home, lost, confused and looking for someone to warm me up

Well I can't help you out there as if I give my driver the night off I usually  walk home with one on either arm and I haven't time of a Friday evening to get over to Warwickshire, forgive me.

But in other news the seasonal forecast is in some doubt in my opinion. I am not saying at this time it is wrong on monthly averages, but if what ever is causing this setup we are in, Canadian warming or whatever, if it persists or reloads and it very well might I can see reloads in December. Then we have possible background signals showing possible cold drivers in Jan/Feb. So very early days, but the seasonals I am not sure had this picked up.