Model output discussion - mid January

[feb1991blizzard]

Is there one of them AAM charts for the EPS? also can I have the link to the chart please?

Also, has anybody got any link to any GWO composites please?

Edited January 25, 2018 by feb1991blizzard

[Daniel*]

23 minutes ago, Snowy Hibbo said:

Yes, it's very encouraging. Would be better if we had a little more Phase 4 and a little less GEFS craziness, but it's definitely encouraging.

Thanks, with MJO in tandem am I right there could be potential for something out the ordinary in terms of cold? It looks deeply interesting to me certainly this winter I don’t think we have had so much going for it.

[ghoneym]

2 hours ago, Tamara said:

Its only an island if you look at it from the water

A textbook example of where an amplitude MJO wave lead the atmosphere on a surging poleward +AAM rally and which in turn created a bitterly cold high latitude blocked pattern from the first week of February and which lasted well into the month was in 1978 

January 1978 closed out having featured a lot of the cold zonal pattern which has featured through quite extensive parts of this winter, and which favoured northern parts of the UK mostly.

 

 

 

 

Just for reference the first image below is the current MJO state and forecast and then below that, what the actual MJO track was in Jan through to March in 1978. I can see a lot of similarities taking shape. As you say though there are many other factors at play which would need to fall into place to achieve on the ground what was experienced in Feb 1978. 

[Daniel*]

^ Also so I believe it has a low AAM bias so even more encouraging I’d say. 

[swebby]

43 minutes ago, ghoneym said:

Just for reference the first image below is the current MJO state and forecast and then below that, what the actual MJO track was in Jan through to March in 1978. I can see a lot of similarities taking shape. As you say though there are many other factors at play which would need to fall into place to achieve on the ground what was experienced in Feb 1978. 

Many thanks ghoneym for flagging the archive mjo site - was not aware and very useful!

i've pasted a link for for ease of access for anyone else http://www.bom.gov.au/climate/mjo/

[CK1981]

I’m guessing, looking at the 1978 charts posted by Tamara, the ideal flow off the continent for real surface cold would be ESE rather than E or NE to prevent North Sea warming?

[Chesil View]

Just now, CK1981 said:

I’m guessing, looking at the 1978 charts posted by Tamara, the ideal flow off the continent for real surface cold would be ESE rather than E or NE to prevent North Sea warming?

Strangely the Great South wezt blizzard in feb 78 fell with uppers of just minus 2 but it was a dry continental feed of air.

Edited January 25, 2018 by Broadmayne blizzard

[CK1981]

6 minutes ago, Broadmayne blizzard said:

Strangely the Great South wezt blizzard in feb 78 fell with uppers of just minus 2 but it was a dry continental feed of air.

I remember reading that somewhere. A direct flow off a very cold landmass would definitely prevent any North Sea moderation.

[Chesil View]

Just now, CK1981 said:

I remember reading that somewhere. A direct flow off a very cold landmass would definitely prevent any North Sea moderation.

Yes it pretty much came across the channel in 1978. Shortest sea track for the south of England.

[SMU]

30 minutes ago, CK1981 said:

I’m guessing, looking at the 1978 charts posted by Tamara, the ideal flow off the continent for real surface cold would be ESE rather than E or NE to prevent North Sea warming?

Yes your correct - although that’s not always the best case for snow-

The best scenario is where the flow is ENE with the flow coming just out of the North coast of Belgium. This way you can maintain a low level of modification of the cold air- but there’s enough sea track to get those towering snow showers !

There are many instances in the archives however if look a little closer to home 2009 & 2013 were all good examples

Optimal uppers are sub -10c for a great thermal gradient -

Notice what’s also important are the low heights - ideally sub 536 DAM

 

some of the GFS / Evolutions are very plausable however what’s also been notable in the last 13 years is even when we get the bubble of pressure over scandi the location is about 300-400 miles further SE than yesteryear meaning the pulse of CAA goes through France & we get modified SE winds...

At least something to look at for the moment....

Edited January 25, 2018 by Steve Murr

[CK1981]

Just now, Steve Murr said:

Yes your correct - although that’s not always the best case for snow-

The best scenario is where the flow is ENE with the flow coming just out of the North coast of Belgium. This way you can maintain a low level of modification of the cold air- but there’s enough sea track to get those towering snow showers !

There are many instances in the archives however if look a little closer to home 2009 & 2013 were all good examples

Optimal uppers are sub -10c for a great thermal gradient -

Notice what’s also important are the low heights - ideally sub 536 DAM

 

some me of the GFS / Evolutions are very plausable however what’s also been notable in the last 13 years is even when we get the bubble of pressure over scandi the location is about 300-400 miles further SE than yesteryear meaning the pulse of CAA goes through France & we get modified SE winds...

At least something to look at for the moment....

Thanks, Steve. It’s all very finely balanced, even when a Scandi high sets up. We either get a very dry flow off the continent, or a North Sea snow maker with cold enough upper air. I guess the ideal, as in February 1991, would be lower pressure over France feeding fronts into the circulation over the U.K.

[tight isobar]

Gonna be very intresting to view todays 12z op/and supports, for the continued cell placements-hp- and there perhaps easterly evolutions.

And yes...hopefully we can finaly in the near-future begin to talk/discuss convective potential.....we live in hope?

[tight isobar]

20 minutes ago, tight isobar said:

Gonna be very intresting to view todays 12z op/and supports, for the continued cell placements-hp- and there perhaps easterly evolutions.

And yes...hopefully we can finaly in the near-future begin to talk/discuss convective potential.....we live in hope?

Edit/quote;

Or is this the true begining of 'cognative dissonance kicking in hard!!!?

Refer-to the moan/ramp thread for guidance...?

Edited January 25, 2018 by tight isobar

[ghoneym]

Very similar GFS / UKMO at + 120

 

         

[Singularity]

 

The mean heading off the scale. Most amusing!

ECMF seems more realistic unless the Nina anomalies erode faster than the current consensus.

 

Should be a good chance of some more GFS runs akin to the 00z cropping up sooner rather than later. Enjoy them when they come! (Okay, if and when - I've been at this game a long time...)

[Methuselah]

Looking promising for a short blast of Arctic air:

[feb1991blizzard]

That shortwave in the Atlantic has knackered us on this run, it stops us pulling down a N'ly.

[inghams85]

1 minute ago, feb1991blizzard said:

That shortwave in the Atlantic has knackered us on this run, it stops us pulling down a N'ly.

Much better longer term tho with the pull back of the mid Atlantic ridge towards greeny land 

Also the shortwave will reinforce low heights in Iberia to prop up the high and pull in some easterly winds

Edited January 25, 2018 by inghams85

[ArHu3]

2 hours ago, CK1981 said:

I’m guessing, looking at the 1978 charts posted by Tamara, the ideal flow off the continent for real surface cold would be ESE rather than E or NE to prevent North Sea warming?

No, that air is already too warm to begin with, you want air with an arctic origin, coldest direction is northeast 

[ACCOUNT DELETED]

13 minutes ago, Ed Stone said:

Looking promising for a short blast of Arctic air:

Not a snow maker in SW UK I wouldn't think with that high being close by but nevertheless plenty of dry, sunny weather so that's very good news after all the flooding in these areas recently 

[feb1991blizzard]

3 minutes ago, inghams85 said:

Much better longer term tho with the pull back of the mid Atlantic ridge towards greeny land 

Also the shortwave will reinforce low heights in Iberia to prop up the high and pull in some easterly winds

It should be a better run than the 6z, it depends on that trough over Newfoundland (I think), we need that to remain slow moving thus pumping up WAA up the western side of Greenland, its not idealy tilted but I think it will just about get the job done.

[SLEETY]

Shame it lasts about 2 secs the arctic outbreak,it’s all too flat again.boring run if your looking for cold ZZZZZZZ

Edited January 25, 2018 by SLEETY

[inghams85]

3 minutes ago, feb1991blizzard said:

It should be a better run than the 6z, it depends on that trough over Newfoundland (I think), we need that to remain slow moving thus pumping up WAA up the western side of Greenland, its not idealy tilted but I think it will just about get the job done.

I would say its not ideally tilted for a greenland high but its a great angle for Iclenadic/Scandinavian blocking! East Based NAO! Also look at that cold pool building in Scandi. Monstrous that!!! Wow

Edited January 25, 2018 by inghams85

[frosty ground]

1 minute ago, feb1991blizzard said:

It should be a better run than the 6z, it depends on that trough over Newfoundland (I think), we need that to remain slow moving thus pumping up WAA up the western side of Greenland, its not idealy tilted but I think it will just about get the job done.

The low (or shortwave as you call it shortwave) forces the high back west.... which mean as it falls across Europe there will be a more potent North Easterly.

[frosty ground]

2 minutes ago, SLEETY said:

Shame it lasts about 2 secs the arctic outbreak,it’s all too flat again.boring run if your looking for cold ZZZZZZZ

Very boring and no Cold insight,