Model Output Discussion - January 11th.

[Harsh Climate]

I think the high over us is going to retrogress northwards to greenland giving us a big northerly.

[andy_leics22]

ECM is beautiful!!

To back up what I said yesterday about not taking each run as gospel and comparing the 00z to say the 06z... Here is a comparison from todays 00z and 06z for next Thursday night, quite a big difference...

[IDO]

GFS_06Z

-Again late in FI, the PV moves East and gives us a shot?

[Harsh Climate]

Just as I thought.

[Lewesdon]

Quick question from a newbie. What is WAA?

[Radiating Dendrite]

Just as I thought.

But it topples and leaves us with a bit of PV over the top of us.

The GFS is laughable at the moment, as is always the case with a pattern change it goes AWOL for a few days, only to return to its senses a little later on.

Quick question from a newbie. What is WAA?

Warm Air Advection.

[Harsh Climate]

But it topples and leaves us with a bit of PV over the top of us.

The GFS is laughable at the moment, as is always the case with a pattern change it goes AWOL for a few days, only to return to its senses a little later on.

Warm Air Advection.

Yes but look whats coming

[KTtom]

http://www.wetterzentrale.de/pics/Rtavn3121.png

The world kite flying championships in SE Greenland should be interesting!

[No Balls Like Snow Balls]

GFS 06Z not bad from the point of view that it would be cold and frosty all of next week if it were to verify. Still we are looking at the cold hanging on until at least Monday for sure. Cold days and frosty nights, at least it's gonna feel like winter :-)

[Harsh Climate]

http://www.wetterzen...s/Rtavn3121.png

The world kite flying championships in SE Greenland should be interesting!

A windchill of perhaps -70C? lol

[Nick F]

This is all getting a bit frustrating though, and potential for deep cold and snow for the UK still remains out of reach, even though we've had lots of interesting scenarios thrown at us over the last week. Carrot on the end of a stick and all that. There are still major hurdles to overcome IMO:

1. Strong PV reluctant to leave Greenland and ridging dominating over western Europe

which is directly correlated to

2. Strong jet across the N Atlantic which is way north of the UK and only dives equatorward to the east of the UK, hence the troughing/cold remaining over eastern Europe.

Unless the PV over Greenland fragments or retrogresses, I'm afraid deep cold is unlikely to attack us from the north or east. The UK probably in the worst positions right now in terms of placement for cold and snow.

[winterof79]

A some stage i believe a good chunk of the PV will visit us

http://www.wetterzentrale.de/pics/Rtavn3361.png

http://www.wetterzentrale.de/pics/Recm2401.gif

[ITSY]

as per usual we have cold then mild scenarious thrown at us - ECM 00Z is excellent for a cold set-up and GFS 06Z is anything but. Be interersting to see the ensemble graph for GFS, i reckon the 06z must be a mild outlier of sorts - as of course the ecm operation was, to an extent. The ECM control of earlier was the coldest run of the bunch!.

Edited January 12, 2012 by ITSY

[weathe20]

Is this what people here are trying to see evolve in the charts?

[Radiating Dendrite]

Is this what people here are trying to see evolve in the charts?

Yes, in an ideal world.

But I think the easterly may now be a bit of a non starter.

ONE QUESTION FOR THE BRAINS - the 1991 chart has a strong PV over Greenland. Why did that Easterly come off, yet the chances of us getting one this time are very low?

Edited January 12, 2012 by Radiating Dendrite

[nick sussex]

Yes, in an ideal world.

But I think the easterly may now be a bit of a non starter.

At this rate thats got more chance than the trough digging se into Europe!

Regarding the amplification off the eastern USA if thats a halfway house between the ECM and GFS then you end up in a stalemate so you either want the ECM option or one where the jet heads out of the USA and continues to head ne, its still a slog to get cold pooling in from the east though. Actually slog seems to sum up the output at the moment.

But if the GFS operational run wasn't used by NOAA past day 4 earlier then this may also be barking up the wrong tree.

[winterof79]

Yes, in an ideal world.

But I think the easterly may now be a bit of a non starter.

ONE QUESTION FOR THE BRAINS - the 1991 chart has a strong PV over Greenland. Why did that Easterly come off, yet the chances of us getting one this time are very low?

I am far from brainy,but back then our high ridged north and with the heights over North America they both squeezed the living daylights out of the PV. http://www.wetterzentrale.de/pics/archive/ra/1991/Rrea00119910206.gif

By the 9th it had gone.Probably a lot more to it than that.

[BLAST FROM THE PAST]

Nick UKMO looks subtly better at 120 to me. If this is the start of it coming on board I wouldn't be surprised to see an acceleration of colder synoptics developing. I don't mean within 5 days a freeze will be upon us but a big move forward. TRhats 3 runs in a row now by ECM where we see a chance of major cold push coming, are seeing the consistency needed now? Is the penny dropping? I am pretty pleased with the way the output is developing and progress and the change is IMO already underway.

IMHO I see a 1986 scenario developing here.

BFTP

Edited January 12, 2012 by BLAST FROM THE PAST

[weathe20]

Lots going on in the atmosphere, with signs of plenty of changes ahead with this much divergence >

[ICETAB]

Lots going on in the atmosphere, with signs of plenty of changes ahead with this much divergence >

That forecast is poor compared to what we have seen in previous days. Not good IMO

[Zakos]

Block is modelled to be significantly stronger on the 06z . Russian high loooking stronger aswell. No noteable cold yes, but another upgrade of similiar magnitude could see a scandi high forming at some point?

[john mac]

Nick UKMO looks subtly better at 120 to me. If this is the start of it coming on board I wouldn't be surprised to see an acceleration of colder synoptics developing. I don't mean within 5 days a freeze will be upon us but a big move forward. TRhats 3 runs in a row now by ECM where we see a chance of major cold push coming, are seeing the consistency needed now? Is the penny dropping? I am pretty pleased with the way the output is developing and progress and the change is IMO already underway.

IMHO I see a 1986 scenario developing here.

BFTP

Great post!! I completely agree with you. IMO the ECM is becoming more consitent with this situation with each day that passes. The GFs has gone through the whole card pretty much, throwing different scenarios at us with each run that comes out. I'm expecting the Ukmo to start suppoorting the ECM in the next couple of runs, and while we cannot dismiss the GFs completely, it does seem like The ECM as a better grip on the set up.

[Radiating Dendrite]

That forecast is poor compared to what we have seen in previous days. Not good IMO

Yes I agree.

The mean had previously been trending under 0 comfortably.

Good news on the UKMO, but how many times are we going to be told the change is coming?

Block is modelled to be significantly stronger on the 06z . Russian high loooking stronger aswell. No noteable cold yes, but another upgrade of similiar magnitude could see a scandi high forming at some point?

Not if we do not get an undercut.

The block can be as strong as it wants, but if it just merges with the Azores high then it will be of little use.

Edited January 12, 2012 by Radiating Dendrite

[Harsh Climate]

Awful esembles! Just about all 20 pepetrations are poor.

Hopefully the ECM will show us a good run tonight and come up trumps, really showing how fickle the gfs can be

[weathe20]

That forecast is poor compared to what we have seen in previous days. Not good IMO

Its the divergence I was talking about. The models remain volitile and un-decided if you ask me.