Model output discussion - proper cold spell inbound?

[bradymk]

Meanwhile the GFS with it’s best Atlantic output so far......

[bluearmy]

9 minutes ago, ICE COLD said:

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 ?

Just as the higher resolution of the ec op can cause it to ‘over react’ and show over amplification in the trop, then perhaps the same rules apply higher up.  It had thrown out 4 fairly consistent solutions. It had some eps cluster support though not particularly strong eps slp support.  It could just be a dodgy suite (re the AO numbers). only 8 hours to wait! 

[Ice Day]

A couple of excellent and sobering posts this morning from BA and John Holmes, which highlights so well that even with lots of background signals in our favour, nothing can be assumed. 

Moving onto this mornings 6z, out to 174 and it's looking pretty good thus far and is on the same page as yesterday's ECM and has stronger heights up towards Greenland than the 0z.  

[ICE COLD]

1 minute ago, bradythemole said:

Meanwhile the GFS with it’s best Atlantic output so far......

Yep at 180 hrs looks good 

[ICE COLD]

What is confusing me is why the PV is still strong over Canada when you have this happening there ? 

[karlos1983]

A recurring theme seems to be to drag heights above the uk!

is the theme set?

[Ali1977]

6 minutes ago, karlos1983 said:

A recurring theme seems to be to drag heights above the uk!

is the theme set?

Looks like another good run coming, I'll watch it play out but if it and the ENS go colder than the last suite I'll be v happy, and for now hope the ECM is wrong!!  This is day 8, and although the SSW makes models a bit variable from time to time you have to think this GFS run has a chance of being in the right ball park - should the ENS follow that is.

Id think there would be some very cold nights on this run, slack flow off the continent which is now pretty cold.

Edited February 10, 2018 by Ali1977

[ICE COLD]

For comparison Day 8 GFS first ECM second . No want one I like . 

[TEITS]

Going to disagree with John H here.

Plenty of support that our weather will eventually be coming from the E over the next 14 days even despite this mornings ECM.

For starters we have the GEM & GFS Operationals and looking at the UKMO +168 that is heading the same way. More significantly is the GEFS mean at +300 plus has consistently suggested a flow from the E.

Evidence of blocking to our N & E continues to be suggested by the models and a flow from the E/NE looks favourite. However the depth of cold is impossible to predict at the moment,.

[bluearmy]

1 minute ago, ICE COLD said:

What is confusing me is why the PV is still strong over Canada when you have this happening there ? 

Well that’s at 10 hpa and the vortex on the trop output is at 500 hpa.

if that warming verifies next Sunday then I doubt there’s will be a strong e Canadian trop vortex a week or so later though a vortex will probably survive somewhere over Canada .........

[Wivenswold]

1 minute ago, TEITS said:

 

Evidence of blocking to our N & E continues to be suggested by the models and a flow from the E/NE looks favourite. However the depth of cold is impossible to predict at the moment,.

Can we post this hourly on here to keep the hype down?

[bluearmy]

1 minute ago, TEITS said:

Going to disagree with John H here.

Plenty of support that our weather will eventually be coming from the E over the next 14 days even despite this mornings ECM.

For starters we have the GEM & GFS Operationals and looking at the UKMO +168 that is heading the same way. More significantly is the GEFS mean at +300 plus has consistently suggested a flow from the E.

Evidence of blocking to our N & E continues to be suggested by the models and a flow from the E/NE looks favourite. However the depth of cold is impossible to predict at the moment,.

Agreed Dave - it’s just the accelerated easterly flow that’s in question .......

and of course, the longer it takes to establish, the ‘ if it can go wrong ...’ comes into play !

[SMU]

The 06z - now all but identical to the JMA yesterday looks a fair match for the transitional process post warming

If this is going to move onto something Epic ( which it has a good chance to do ) then the polar regions will 'fill up' with High pressure a few days after this initial wave - with repetative Energy bursts of WAA...

Edited February 10, 2018 by Steve Murr

[Chesil View]

All I would say regarding the ups and downs of op output is that the Met office remain bullish on the effect of ssw probably bringing cold to the uk.

Its worth remembering

1. They are the world leaders in forecasting.

2 They have access to far more detailed modelling than almost everyone on here.

[Frosty.]

There is even more support from the GEFS 00z for a late Feb freeze than there was yesterday, plenty of positives again so far today!!

[nick sussex]

A very bizarre morning!

The GFS which wasn't interested now seems to be moving to the original ECM solution on its 06hrs run but looking at the ECM ensembles any colder easterly solutions seem to have been put back past the 20th.

There does seem to be constant chopping and changing with high pressure cells to the north and northeast  and now the GFS 06hrs run develops much more amplitude upstream compared to the flat as a pancake ECM.

 

[Ali1977]

2 minutes ago, Steve Murr said:

The 06z - now all but identical to the JMA yesterday looks a fait match for the transitional process post warming

If this is going to move onto something Epic ( which it has a good chance to do ) then the polar regions will 'fill up' with High pressure a few days after this initial wave - with repetative Energy bursts of WAA...

At 228 we need that extra burst of WAA to reinforce the HP west of Greenland - PV is weak on the south tip of Greenland which could help. 

[Frosty.]

4 minutes ago, Frosty. said:

There is even more support from the GEFS 00z for a late Feb freeze than there was yesterday, plenty of positives again so far today!!

And here is my evidence, pretty comprehensive i think most will agree!!❄❄❄❄❄❄❄❄❄

[That ECM]

T192 looking forward to seeing output in a couple of days time when we can get a better idea what the ukmo is showing  and being able to see the nh profile for this time period. 

[Shunter]

at T+288 the GFS OP gives Eastern Europe an early taste of spring !

It couldn't, could it ?

#Easterly Zonal

 

[SLEETY]

Anything can happen in fl in gfs land,complete waste of ram space,whatever it shows lol.

Stick with what the met are saying regarding this very cold Easterly  ,they have access to models which run at a far higher resolution than gfs can ever hope for yet.

 

[The PIT]

Some good words by BA and John H. Even if we do get blocking there's no guarantee it will be in the right place for the UK. Until there's a firm theme in deep FI land rather than toying with ideas then discarding them and not moving them forward I wouldn't get two excited yet.

[SMU]

GFS mean @150 V 156 shows a nice shift to the atlantic block-

[ICE COLD]

5 minutes ago, Steve Murr said:

GFS mean @150 V 156 shows a nice shift to the atlantic block-

The control pretty much follows the op and then does this ?

[Day 10]

So another morning of runs are just about coming to an end and the volatile nature of the output continues, hardly surprising giving the nature of the atmosphere right now. Yes the weather is always chaotic so throw into the mix the beginnings of a strong Sudden Stratospheric Warming and the models are bound to struggle.

I expect the output to continue in this vein for a while yet, no despondency from me only intrigue into how everything is unfolding. I think at least another week of rain interspersed with wintry showers or snow for some is on the cards, this weekend being the perfect example, rain in England & Wales today, snow in Scotland/Northern & Ireland and snow showers for some tomorrow.

 

As some have already alluded to the dates of 18th, 19th 20th are when things could become far more interesting as blocking may start to setup somewhere between the North and East of the UK drying things out, but at the same time eventually and hopefully ushering in Winter proper and of course this then brings the threat of country wide snow.

Don't be surprised to one minute see holy grail charts and the next not so good while the models are still getting to grips to this irregular pattern.

I will end on this chart from the other day, not saying this is what we will end up with but it wouldn't surprise me if charts like this pop up again before the week is out.

For once we have a number of signals all heading in the right direction so let's hope we finally hit the jackpot!