Model Output Discussion 18th Nov.2013-12z onwards.

[syed2878]

i c the ecmf toying with another northerly again at oh yes 240h take the ecmf and gfs from last week and i beleave the gfs done quite well. I think the gfs is good at picking out patern changes better than the ecmf far out.

[East_England_Stormchaser91]

Hmmm, looks as if the GFS, yes I cant believe I'm saying it may be onto something here, would not take alot for that high to just pop up to Greenland and flood those -15 uppers down to us. Interesting model watching. Love the build up to winter so much.

[Gavin Hannah]

T.90 bringing that colder air down further south and west. Due to the LP system over Scandi/Siberia is not as intense allowing the isobars to straighten up more and stream further south.  The cold air plunges further south quicker than before and is shaping up to flood into the UK.  

 

 

Edited November 20, 2013 by IBringTheHammer

[Matty M]

Hmmm, looks as if the GFS, yes I cant believe I'm saying it may be onto something here, would not take alot for that high to just pop up to Greenland and flood those -15 uppers down to us. Interesting model watching. Love the build up to winter so much.

Just meaning a massive spread of members.

Here is the EPSgram for London.

[SMU]

We aren't going to get enough track movement west to get into the bitter air & we will always be losing the sinking battle-

 

Maybe colder for longer would be the way to look at it....

 

S

[MKN]

If our high pressure nudged slightly further north and west we could find ourselves in line for a blast of very cold uppers. Trend is definately one of having the high positioned further west and cold air flooding south ever closer with each run

[bluearmy]

A rather flat looking 8-14 dayer from NOAA this evening and they do mention the "z" wordin their discussions. Climate Prediction Center - 8-14 Day 500mb Outlook   An interesting paragraph included in those discussions about beyond week 2 as well. GUIDANCE FOR THE PERIOD BEYOND WEEK-2 HAS BEEN VERY INCONSISTENT OF LATE, WITHTHE ONLY REASONABLE SIGNAL BEING SOME CONTINUATION OF THE QUASI-BLOCKINGPATTERN OVER THE NORTH PACIFIC. TO BE SURE, THIS PATTERN IS ONE OF THE MOREPERSISTENT PATTERNS OF INTERNAL VARIABILITY IN THE EXTRATROPICS DURING WINTER.THE LARGEST UNANSWERED QUESTION OF PERIOD LEADING UP THE CHRISTMAS SEASON ISWHETHER ANY PERSISTENT HEIGHT RISES WILL OCCUR ACROSS PARTS OF THE NORTHWESTERNATLANTIC AND GREENLAND, SOMETHING THAT HAS NOT HAPPENED THUS FAR THIS COLDSEASON. ADDITIONALLY, THE MJO REMAINS FAIRLY INCOHERENT, AND ANY REORGANIZATIONOF THAT IMPORTANT TROPICAL PHENOMENON WILL LIKELY HAVE RAMIFICATIONS FOR NORTHAMERICAN HYDROCLIMATE LATER IN DECEMBER.

'Suppressed zonal' - id take that over here if suppressed meant to our south through the med.

[radiohead]

Look how much has changed since the 0Z GFS run just this morning, for the exact same time, 6pm on 25 Nov

 

0Z run :

 

 

18z run :

 

Edited November 20, 2013 by radiohead

[SMU]

Dare I say why...................... GFS ^^

[damianslaw]

Late November is often a very unsettled wet period as westerlies reach their yearly maximum peak - however, not this year (similiar to 2008, 2010 and 2012 in this respect).

 

The polar vortex is seriously being squeezed by both the aluetian high and the mid atlantic high and the consequent result is trough action over scandinavia - never a bad thing if you are looking for a potential sustained cold outlook.

 

The models continue to show a very amplified pattern and provided we hold the current northern hemispheric profile, it wouldn't take much for another more potent arctic blast to invade the country before the months end.

 

Its an interesting synoptical set up for the time of year- but one that could go anywhere at the same time.

[Rocheydub]

If our high pressure nudged slightly further north and west we could find ourselves in line for a blast of very cold uppers. Trend is definately one of having the high positioned further west and cold air flooding south ever closer with each run

Read Steve's post above. He understands the nuances of each model more than any man!

[shaky]

Look how much has changed since the 0Z GFS run just this morning, for the exact same time, 6pm on 25 Nov

0Z run :

18z run :

oh my days thats a frikkin huuuugge change!!anything can happen now if it can change that much in 12 hours.

[Gavin Hannah]

I think one thing is clear for next week.  Europe looks like being in the freezer.

 

(Would help if i posted the correct charts lol....)

Edited November 20, 2013 by IBringTheHammer

[Gibby]

oh my days thats a frikkin huuuugge change!!anything can happen now if it can change that much in 12 hours.

Yes it can change back again in another 12 hours.

[Matty M]

I await the Ensembles now, as no point looking at rest for the time being.

 

The 72-108hr period is crucial.

[shaky]

Yes it can change back again in another 12 hours.

or can change for the better cold wise!!

[Cloud 10]

'Suppressed zonal' - id take that over here if suppressed meant to our south through the med.

 

'Suppressed zonal' is a new one on me,although it seemed more related to the conus

[Rocheydub]

Yes it can change back again in another 12 hours.

BOOOOOM!

 

Have been here for a few years now, and the variances of different runs matter little IMO. The overall picture painted by the models remain the same. Anticyclonic, cool and cold by night, widespread frosts and fog and little if any precipitation. 

 

Deep FI teases yet again. How odd!!! Jam tomorrow. If it gets within T-144 then lets talk, until then…. I have no faith. Once bitten, twice/thrice shy!

[Cloud 10]

Where will the 18z take that high pressure anomaly after 168hrs?

 

[Bristawl Si]

About as poor as it can get on the ECM 10 day mean tonight. http://www.wetterzentrale.de/pics/Reem2401.gif

A lot can ACTUALLY change in 10 days though, with these computer weather-related outputs though. I never take much notice of charts past 4 or 5 days.

[radiohead]

BOOOOOM!

 

Have been here for a few years now, and the variances of different runs matter little IMO. The overall picture painted by the models remain the same. Anticyclonic, cool and cold by night, widespread frosts and fog and little if any precipitation. 

 

Deep FI teases yet again. How odd!!! Jam tomorrow. If it gets within T-144 then lets talk, until then…. I have no faith. Once bitten, twice/thrice shy!

 

Well the varinances of runs certainly matters in Europe where the colder air for Monday has shifted from Russia to France in less than 24 hours of model runs.

[Skyraker]

Is that an energetic southern arm I see before me?

 

Edited November 20, 2013 by Skyraker

[swfc]

I await the Ensembles now, as no point looking at rest for the time being.

 

The 72-108hr period is crucial.

Id agree.its a very subtle change ie the rise in pressure but it could build during tom

[Mucka]

Is that an energetic southern arm I see before me?

 

 

Quite different to the 12z at the same point but probably just run to run variability.

[radiohead]

There is significance in the westward advancement of colder air across Europe on each subsequent GFS run today and the difference colder air in Europe makes with regard to the collapsing/propping of the high and/or a potential easterly flow down the road.