Model Output Discussion 1st Nov.2013

[Cheshire Freeze]

But Cold

 

 

Bitterly cold out into FI

[johnholmes]

The height The height predicted for English channel is about 6dm lower than 4 days ago and the flow on both 6-10 and 8-14 is n of west which is pretty different to 4 days ago when I last saw them and did my post in the technical thread.

The odds then I felt were against this pattern developing, see my last pdf, but with the probability that it could happen. It looks as if the lesser probability may well occur based on what I have seen so far. Not having seen any 500mb anomaly outputs since the 00z Friday ec-gfs I am not yet totally sure but it does look like yet again the anomaly charts gave a decent indication and a consistent one about a week ahead of a pattern change.

One thing which few will believe is that the small rise in the 30mb basic chart I use did give an indication that this might happen around the 3^rd week in November. That is in the very simplistic way I use it. It gave such indications in my view in 3 previous early winters but I suspect the more knowledgeable folk with Stratopshere work will not accept my suggestion for this. It went against every other teleconnection, MJO, AO, NAO, PNA and 500mb anomaly charts as far ahead as they went.

Never mind I am sure the cold lovers will be happy whatever anything shows if it snows in their back yard. Not time now but I will do an in depth look at the anomaly charts when I get time.

In the meantime below are the anomaly charts from today.

Ec-gfs

http://www.meteo.psu.edu/~fxg1/ECMWF_12z/hgtcomp.html

noaa

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

[Snowman.]

PV is being tested from two angles.

 

 

Lets hope we can keep this.

[radiohead]

Interesting chart. Pity it's late November and not in late January with colder air!

 

[garbagebags]

Cold seems to be pushed back a good 24 hours. 

[bradymk]

Interesting to see what GFS FI does with Euro low. GFS is liking the idea of the high moving to Scandi with LP over Europe. CFS weekly backing this up too.

[Captain Shortwave]

Well the GFS in low resolution ups the ante on the jet,  but the high can't sink into default position and ends up over Scandinavia bringing in a bitterly cold easterly.

There is no need to worry, with low heights in the med, you can't get a Euro or bartlett high set up for quite some time.

Best low resolution run I've seen to be honest, then to top it off, the high splits and gives us another strong Atlantic ridge with a northerly, last frame we would be seeing a rinse and repeat with heights building over Scandinavia again.

Edited November 11, 2013 by Captain shortwave

[Cheshire Freeze]

PV being mauled to death deeper in FI

 

[Jason T]

Its just one run and its the 18 z. It got in the pub late, 

 

12 Z T192, 528 COVERING 95% of the UK.

 

 

 

 

18z t192 528 further north.

 

 

[NorthernRab]

PV is being tested from two angles.

 

 

Lets hope we can keep this.

 

The Atlantic and Siberian highs are hardly being kind to it either. 

[AWD]

12z NAEFS suite showing an increasingly prominent Mid Atlantic ridge scenario in the 8-10 day timeframe, seemingly backing up tonight's Operational output;

Still hints that the pattern could become west based in the longer timeframe, although as we would expect at that range, much more deviation and thus low confidence by then!

[Barry12]

Its just one run and its the 18 z. It got in the pub late, 

 

12 Z T192, 528 COVERING 95% of the UK.

 

 

 

 

18z t192 528 further north.

 

 

The cold lasts the whole run though

 

[cold snap]

18z GFS ,crazy run.

But there isn't sufficient blocking ,it's just the fact that the Atlantic is showing 0 zero interest taking part for some bizzare reason ,it has room to get round that high but doesn't want to.

This has to be a small concern for cold lovers once we start hiting the reliable timeframe scale .

It's a brilliant run ,but with out heights tucked up around Greenland , the foundation is on shaky ground.

Having said that it maybe the outcome , I hope so.

Edited November 11, 2013 by cold snap

[Mark Neal.]

An interesting GFS: many quick to jump the gun an see it as a downgrade,however longer term much better this op, Blocked Atlantic, Better pressure orientation towards NW. PV getting well worked at towards FI. Interesting. Small steps...

[Cheshire Freeze]

GFS ~240 hrs

 

 

November 1962

 

[cold snap]

An interesting GFS: many quick to jump the gun an see it as a downgrade,however longer term much better this op, Blocked Atlantic, Better pressure orientation towards NW. PV getting well worked at towards FI. Interesting. Small steps...

The Atlantic isn't blocked that much

[Mark Neal.]

The Atlantic isn't blocked that much

Not now. In a weeks time with that run, a lot more blocked than recent runs. That's why I was saying a more blocked Atlantic. Very strange as pointed out above the jet stream just goes away from us..Knew it wouldn't be long before Nick Sussex mentioned the S word.. Shortwave that is! Edited November 11, 2013 by Mark N

[nick sussex]

I think we're missing a trigger here to get the cold further south into the UK and Europe so we need to order a shortwave near Greenland to run se ahead of that amplifying wave upstream in the USA.

 

This is low risk for what normally leads to shredded nerves in here, as long as you get that amplification upstream this will force the shortwave se.If you get enough cold into Europe then the high as it topples can draw in a cold east/ne flow.

 

The GFS IMO is a lot more plausible upto 240hrs than the ECM in recent days which has been all over the place in its FI. So as per usual its what happens in the eastern USA that will determine events in Europe, the more amplification there, the further north any high will get, even if the PV then moves east again the topple point is more favourable.

[SE Blizzards]

Beast from the East?

 

 

According to the GFS 18Z anyone searching for any mild weather from this weekend onwards might need these to clutch at...

 

 

 

[StretfordEnd1996]

A weird but respectful run from the 18z in my opinion, have absolutely no concern at all, arguably the worst run of the day in terms of cold some may say, but arguably no where near the worst. Cold is maintained for longer; however it is debatable as to whether it is as strong as previous runs. 

 

No cause for concern in my opinion at all

[garbagebags]

A weird but respectful run from the 18z in my opinion, have absolutely no concern at all, arguably the worst run of the day in terms of cold some may say, but arguably no where near the worst. Cold is maintained for longer; however it is debatable as to whether it is as strong as previous runs.  No cause for concern in my opinion at all

Pretty much a perfect conclusion there.

[Cloud 10]

I think we're missing a trigger here to get the cold further south into the UK and Europe so we need to order a shortwave near Greenland to run se ahead of that amplifying wave upstream in the USA.

 

This is low risk for what normally leads to shredded nerves in here, as long as you get that amplification upstream this will force the shortwave se.If you get enough cold into Europe then the high as it topples can draw in a cold east/ne flow.

 

The GFS IMO is a lot more plausible upto 240hrs than the ECM in recent days which has been all over the place in its FI. So as per usual its what happens in the eastern USA that will determine events in Europe, the more amplification there, the further north any high will get, even if the PV then moves east again the topple point is more favourable.

 

I think the part of your post in bold highlights the rather bizarre nature of the output.

 

Normally there are more shortwaves than you can shake a stick at. 

[cold snap]

I think the part of your post in bold highlights the rather bizarre nature of the output.

Normally there are more shortwaves than you can shake a stick at.

See people have to realise that we don't live in Canada, otherwise we would bank on this now

The shortwave issue is not a huge problem .

We need heights to grow into Greenland.

Edited November 11, 2013 by cold snap

[nick sussex]

I think the part of your post in bold highlights the rather bizarre nature of the output.

 

Normally there are more shortwaves than you can shake a stick at. 

True! normally they're a real pain but in this instance it would help matters, the GFS initially has a flatter pattern because of a shortwave near Greenland which stops more northward ridging of the high, then as the amplified wave runs east it decides then to get rid of the shortwave! When what we wanted to see was that developing and running se. Regardless the GFS 18hrs IMO is the best run of the season so far in terms of trend.

 

I quite like the NAVGEM 18hrs run which is interesting at T144hrs , sadly that model is firmly in the cannon fodder model section in terms of reliability.

[Cheshire Freeze]

GEFS ensemble mean looks to be colder than the 12z suite at 192.... -4 850s down to Manchester now whereas they were held up around the Scottish border on the 12z....-6 850s into Scotland too where they weren't before.