Model output discussion - proper cold spell inbound?

[sundog]

8 minutes ago, s4lancia said:

I was hoping the ECM maybe could go all the way down to T-0 consistently showing blocking in all the right places. Then I woke up. Literally.

Not a blinder this morning from the ECM op, but in all reality a smooth transition from current state to post SSW was never ever on the cards. The models struggle at the best of times, and when you consider how unusual a situation this if for them, and it is, it is hardly any wonder we are getting all sorts of forecasted outcomes.

Like it or not, that’s just how it is, nothing will be even close to nailed down for a good few days yet. Expect further disappointing outputs and further winter wonderland outputs to appear, disappear and reappear from model to model, suite to suite, day to day.

I just can’t wait to get the wind reversal underway later on Sunday. Give it a day or so and then we can see what the charts look like, as the actual data starts getting fed in.

Totally agree. Anyone thinking that the models have any real handle on this atm need to get real. It just isn't worth getting worked up over what's showing on the models atm . No point till later next week in taking the models more seriously.

[snowblizzard]

23 minutes ago, snowblind said:

Just watched it again. He doesn't say that.

He says there are hints with what's going on in the upper atmosphere.....

Sorry, apparently I was watching the earlier update!

[snowblind]

3 minutes ago, snowblizzard said:

Sorry, apparently I was watching the earlier update!

Now worries. It's a more positive update which is good. Also some snow chances for the week ahead as well.

[Polar Maritime]

Just model discusson.

Thanks.

[mulzy]

Disappointing ECM suite this morning.  The eps mean at day 7 doesn't show much Atlantic ridging while the day 10 mean still shows the Canadian segment of the vortex still having an influence.

Maybe the Atlantic height rise horse has bolted in the day 7-9 range?  Tonight will reveal more...  

[Ali1977]

4 minutes ago, mulzy said:

Disappointing ECM suite this morning.  The eps mean at day 7 doesn't show much Atlantic ridging while the day 10 mean still shows the Canadian segment of the vortex still having an influence.

Maybe the Atlantic height rise horse has bolted in the day 7-9 range?  Tonight will reveal more...  

I'm a bit shocked the ECM ENS isn't better, of course ECM could be right.  I'll reserve judgement for a few days and keep an eye on the METO long range and tweets.  ECM ENS and GFS ENS now don't agree at day 10, this I guess is expected when an SSW is in the mix, so I'm pretty sure a few days of topsy turvy forecasts before we have a good idea on which way it goes - deep freeze has more of a chance, but we never get the luck.

[Chesil View]

45 minutes ago, s4lancia said:

I was hoping the ECM maybe could go all the way down to T-0 consistently showing blocking in all the right places. Then I woke up. Literally.

Not a blinder this morning from the ECM op, but in all reality a smooth transition from current state to post SSW was never ever on the cards. The models struggle at the best of times, and when you consider how unusual a situation this if for them, and it is, it is hardly any wonder we are getting all sorts of forecasted outcomes.

Like it or not, that’s just how it is, nothing will be even close to nailed down for a good few days yet. Expect further disappointing outputs and further winter wonderland outputs to appear, disappear and reappear from model to model, suite to suite, day to day.

I just can’t wait to get the wind reversal underway later on Sunday. Give it a day or so and then we can see what the charts look like, as the actual data starts getting fed in.

Very much the case I wouldn,t expect the models to have a real handle on developments in until later this week. All I would. Say is that even allowing for this mornings wobble ECM has been most consistent in modelling at the suggest time frame over the lady couple of days. As ever time will tell.

[Jemma Croton]

56 minutes ago, s4lancia said:

No, it was never the 15th. It has always been around the 18th/19th. The SSW only kicks off on the 12th, give it a chance.

Actually Dr A Butler posted out on twitter showing a VQTR with effects showing from the 15th. This was a few days ago but the 15th date expectation isn’t without foundation

[Jemma Croton]

For anyone bummed out with the flipping and flopping in output just now. The SSW isn’t underway until tomorrow so it certainly doesn’t surprise me that the models can’t decide what to put out. I should imagine that runs from maybe the 18Z tomorrow but certainly 00Z/06Z Monday will start giving a clearer picture once the SSW is actually underway.

Take the charts today and early tomorrow with a shot of tequila (I recommend with cinnamon and orange over salt and lemon) . Yes, there will be the doom-sayers lauding each less favourable run over us but until that SSW (and remember this is a pretty spectacular looking SSW) is underway, don’t let them rain on your parade.

Stay strong snow squad ??❄️

Edited February 10, 2018 by Jemma Croton

[MR EXTREMES]

Just trying to settle model nerves but yesterday mornings gem model run was the same as today's ECM nightmare run.

But today the gem is a blinder.

JMA last night's run also shows northern blocking in the right place.

Navgem gets there,

ukmo I suspect would get there.

There really is no reason to take this morning ECM as gospel.

Today's gem chart 

Identical to recent ECM runs.

 

 

[ICE COLD]

46 minutes ago, mulzy said:

Disappointing ECM suite this morning.  The eps mean at day 7 doesn't show much Atlantic ridging while the day 10 mean still shows the Canadian segment of the vortex still having an influence.

Maybe the Atlantic height rise horse has bolted in the day 7-9 range?  Tonight will reveal more...  

What about the exstended eps mulzy please ? 

[bobbydog]

i'm wondering if the reason we are seeing so much volatility in the models, is due to the zonal wind reversal, possibly being outside of the normal parameters of their programming-

it literally drops off the scale!

[mulzy]

3 minutes ago, ICE COLD said:

What about the exstended eps mulzy please ? 

Days 11-13 shows the lower heights to the west having more of an influence but we do get a decent set up with very strong heights directly to our north by day 15.

[That ECM]

4 minutes ago, mulzy said:

Days 11-13 shows the lower heights to the west having more of an influence but we do get a decent set up with very strong heights directly to our north by day 15.

That kind of fits with a high drifting over us and then drifting north/ ne. 

[Summer Sun]

UKMO extended looks like it begins to move towards a northwesterly at t168

[ICE COLD]

Can't believe the ECM has done this to us again ?. I though the ecm had better resolution on the strat ? Obviously it's not a done deal but you get the feeling when the ecm flips to an output not so good for us coldies it's onto something ?. Mind you the GEFS are good set on the 00z . Maybe it's going to be a waiting game till the last 3rd of the month , when the SSW really takes affect . 

[winterof79]

10 minutes ago, Summer Sun said:

UKMO extended looks like it begins to move towards a northwesterly at t168

Looks similar to GFS

If you run days 5 6 and 7 on UKMO you can see the ridge come more into play 

[Met4Cast]

The models were always going to flip and flop, they do this at the best of times let alone when there's a SSW and a full near record breaking zonal wind reversal, the models need to get to grips with all the different parameters, they're going to struggle.

We're talking charts that are 10-15 days away. I had a feeling that the response was a little "too fast" even with a QTR, all is not lost though, just the natural variability of the models. We've got at least 5 days for them to change to something more favourable again.

[bluearmy]

We can’t have our cake and eat it

12 hours ago the mantra was that ecm high res is the best tool to manage this scenario with its better handle on strat/trop interaction. what now? 

And the idea that the nwp just can’t handle the consequences of this ssw a couple of days before it occurs is also far fetched. A week or so away - yes I can buy that but it’s beginning tomorrow night! The same model that show us what it thinks will be happening next Saturday is the same one that models the ssw within the same dynamic representation on Monday.  The trop response is well within the high res part of the gefs and the eps. The ec op ridge had 25% cluster support yesterday and I suspect it might be less this morning. The gefs suite is now showing around  25% support for this fella headed north. 

the ops are not reliable post day 5/6. We know that. So we shouldn’t be surprised by a lack of consistency. It’s a shame that ecm has jumped ship on the accelerated amplification this morning but it could get back on board later today. one ‘dodgy’ op is always feasible. Two, as we got so close to the reversal would be tough and could well pull down the curtain on a scandi ridge establishing before the 20th. 

What seems pretty clear from all the extended eps modelling is that we will become blocked to our north and northeast  post day 10.  the key to getting very wintry surface conditions here will be dependant on the euro profile. This seems rather less certain. Getting heights to drop close enough to advect deep cold this far could prove tricky. we could well go into a cold frosty anticyclonic spell and be relying on a strike from a meandering cold pool headed west or an approach from the Atlantic pushing ne into the cold air to see any widespread snowcover. (Ignoring what may fall prior to all this with the cold Pm flow)

looking at Berlin and the weather is cool website, yes there is a qtr but just how strong is it by the time it reaches 500 hpa and what latitude is it affecting ? Not very is the answer and north of 65 seems to be the answer. . Of course it doesn’t have to be so strong - you aren’t expecting to see the systems headed in reverse. We just need to flow to slow down enough for some sustained HLB to take hold. 

Something to bear in mind is the eps from that 00z run failed to take the AO negative until the 22nd and then it’s fairly muted. That’s about a week behind the gefs and gems. It could be that the entire suite is unreliable. Or it could be that the model is resolving what happens in the strat/trop better than the other two! the ec op strat profile this morning showing the remnants of that Asian vortex chunk becoming a pain in the way it ‘phases’ with the Canadian, moreso lower down. this could well be interfering with any ‘uber accelerated response’ for us and meaning we have to hang on for another few days and hope nothing else ‘pops’ up to interfere further! 

Going to remain busy in here for a while yet! 

Edited February 10, 2018 by bluearmy

[karlos1983]

Adois La Niña 

 

[london-snow]

1 minute ago, ICE COLD said:

Can't believe the ECM has done this to us again ?. I though the ecm had better resolution on the strat ? Obviously it's not a done deal but you get the feeling when the ecm flips to an output not so good for us coldies it's onto something ?. Mind you the GEFS are good set on the 00z . Maybe it's going to be a waiting game till the last 3rd of the month , when the SSW really takes affect . 

 

Think I read that the ssw don’t take effect until tomorrow (I think?) add to that what bobbydog has stated above. I honestly don’t think we will see a true handle on our patterns going forward until such factors play out and drip and feed down into the various output we see day in and out. 

Not one for the faint hearted for sure but I have faith in the brilliant knowledgeable posters who have called for a potentially very cold pattern to emerge and backed up by the met who have not changed their tune for well over a week.

[johnholmes]

The post above by ba is perhaps the most constructive one I have seen since the anticipated reaction to the 'warming' and how it 'might' affect the UK.

I have to confess to being at odds with a lot of the euphoria on here and not really convinced by my ex colleagues at Exeter over this deep cold possibility from a point east of the UK. Staying colder than normal into the next 2 weeks I quite agree with but to me, most of what I can see from this forum and data we can all pick up from various weather centres suggests that the cold is going to come from a westerly not easterly point, more like NW and at times perhaps N. That is in the 14 day time scale from now. What happens beyond is not my sphere.

The 500 mb anomaly charts are not as solid as needed for a definite take but all 3 I use have consistently shown height rises across much of the northern part of our hemisphere but with not much, to me, to suggest that any upper or indeed surface ridging is going to come from other than the Iceland/Greenland area, again I stress in the next 14 days.

The upper heights from northern Russia all the way across into the far NW of N America mean that the surface lows may well end up being further south than currently. Behind one of these I suspect a burst of polar air is likely. Beyond that then I am uncertain how it may play out. If the expected effect on the Troposphere occurs in our area at such a time then the snowy wonderland so hoped for on here might well happen-I don't know.

Bit coldish, even cold at times is the weather for 2 weeks or so.

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[ICE COLD]

25 minutes ago, bluearmy said:

We can’t have our cake and eat it

12 hours ago the mantra was that ecm high res is the best tool to manage this scenario with its better handle on strat/trop interaction. what now? 

And the idea that the nwp just can’t handle the consequences of this ssw a couple of days before it occurs is also far fetched. A week or so away - yes I can buy that but it’s beginning tomorrow night! The same model that show us what it thinks will be happening next Saturday is the same one that models the ssw within the same dynamic representation on Monday.  The trop response is well within the high res part of the gefs and the eps. The ec op ridge had 25% cluster support yesterday and I suspect it might be less this morning. The gefs suite is now showing around  25% support for this fella headed north. 

the ops are not reliable post day 5/6. We know that. So we shouldn’t be surprised by a lack of consistency. It’s a shame that ecm has jumped ship on the accelerated amplification this morning but it could get back on board later today. one ‘dodgy’ op is always feasible. Two, as we got so close to the reversal would be tough and could well pull down the curtain on a scandi ridge establishing before the 20th. 

What seems pretty clear from all the extended eps modelling is that we will become blocked to our north and northeast  post day 10.  the key to getting very wintry surface conditions here will be dependant on the euro profile. This seems rather less certain. Getting heights to drop close enough to advect deep cold this far could prove tricky. we could well go into a cold frosty anticyclonic spell and be relying on a strike from a meandering cold pool headed west or an approach from the Atlantic pushing ne into the cold air to see any widespread snowcover. (Ignoring what may fall prior to all this with the cold Pm flow)

looking at Berlin and the weather is cool website, yes there is a qtr but just how strong is it by the time it reaches 500 hpa and what latitude is it affecting ? Not very is the answer and north of 65 seems to be the answer. . Of course it doesn’t have to be so strong - you aren’t expecting to see the systems headed in reverse. We just need to flow to slow down enough for some sustained HLB to take hold. 

Something to bear in mind is the eps from that 00z run failed to take the AO negative until the 22nd and then it’s fairly muted. That’s about a week behind the gefs and gems. It could be that the entire suite is unreliable. Or it could be that the model is resolving what happens in the strat/trop better than the other two! the ec op strat profile this morning showing the remnants of that Asian vortex chunk becoming a pain in the way it ‘phases’ with the Canadian, moreso lower down. this could well be interfering with any ‘uber accelerated response’ for us and meaning we have to hang on for another few days and hope nothing else ‘pops’ up to interfere further! 

Going to remain busy in here for a while yet! 

Hi BA 

Do you reckon it may of been an over reaction to SSW in the ECM op runs bringing in the HLB runs ? What I mean by this is that its showed it to early and the effects off the SSW won't be felt until the last 3rd of the month as per the meto and BBC long rangers ? TIA 

EDIT - or am I just trying to make myself feel better ?

Edited February 10, 2018 by ICE COLD

[london-snow]

14 minutes ago, johnholmes said:

The post above by ba is perhaps the most constructive one I have seen since the anticipated reaction to the 'warming' and how it 'might' affect the UK.

I have to confess to being at odds with a lot of the euphoria on here and not really convinced by my ex colleagues at Exeter over this deep cold possibility from a point east of the UK. Staying colder than normal into the next 2 weeks I quite agree with but to me, most of what I can see from this forum and data we can all pick up from various weather centres suggests that the cold is going to come from a westerly not easterly point, more like NW and at times perhaps N. That is in the 14 day time scale from now. What happens beyond is not my sphere.

The 500 mb anomaly charts are not as solid as needed for a definite take but all 3 I use have consistently shown height rises across much of the northern part of our hemisphere but with not much, to me, to suggest that any upper or indeed surface ridging is going to come from other than the Iceland/Greenland area, again I stress in the next 14 days.

The upper heights from northern Russia all the way across into the far NW of N America mean that the surface lows may well end up being further south than currently. Behind one of these I suspect a burst of polar air is likely. Beyond that then I am uncertain how it may play out. If the expected effect on the Troposphere occurs in our area at such a time then the snowy wonderland so hoped for on here might well happen-I don't know.

Bit coldish, even cold at times is the weather for 2 weeks or so.

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

Hi John,

I am no expert in stratospheric warming’s and what goes on high up. What I have read through is that we are looking at around day 10 say 20th a tad before or after for the effects of this warming, We may or may not see cold nirvana but a ssw increases the chances of winds coming from a eastern source. 

I know you hold your 500 anomaly charts in high regards but at two weeks out perhaps it does not factor in the above and other factors that may have a big influence on why others and your ex colleagues at the met see it differently?

Edited February 10, 2018 by london-snow

[ICE COLD]

Day 7 and now GFS looks better than the ECM . You couldn't make it up ? ? GFS 6z top image ECM bottom image .