Model Output Discussion 17th Dec.2013-12z onwards.

[Cloud 10]

thanks for posting that but no-it was the 8-14 day 500mb NOAA chart issued 1 January 2010.

In answer to Tamara I am still not convinced but maybe best we leave our differences and move on.

If anyone, unlikely, is interested enough then the post No was 44 issued 1 January 2010 with my ideas of what the weather might do out to 21 January. It is somewhere in the Net Wx files I suppose.

 

Hi John,i think this is the one you are after.

 

 

 

The archives for these charts are in the link below and go back to 2001. 

 

Climate Prediction Center - Monthly Verifications

[johnholmes]

Hi John,i think this is the one you are after.

 

814hghts.20100101.fcst.gif

 

 

The archives for these charts are in the link below and go back to 2001. 

 

Climate Prediction Center - Monthly Verifications

 

wow, never seen that link before so thanks very much, yes that is the chart

[SMU]

Guys watching the JMA the low off the states goes under the block- & is inconsistent with the GEM & ECM-

 

However it is inline with the GFS-

 

It really boils down to the low going significantly south or significantly north- just NOT THROUGH THE MIDDLE!!!!

 

 

18z out to 96, more heights into scandi.....

 

Remember to get cold we are seeking the triangle of highs in this scenario- Scandi, Kumchatka & Atlantic...

 

S 

[SMU]

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-2-168.png?18

 

Another snowy run for the west as the trough digs south in exceptionally cold westerly air sourced out of the Canadian vortex seen here-

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-6-174.png?18

 

S

[Joe Levy]

This chart from the 18z is nice for coldies. It brings low thicknesses and fairly low uppers to our shores, with wintry potential lying therein. Nothing major, but interesting nonetheless.

[swfc]

Much better profile on the 18z and that piece of pv moving off the ns has been dropped.chances of that atlantic low diving south east at 180hrs?????

[Blizzardof82]

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-2-168.png?18

 

Another snowy run for the west as the trough digs south in exceptionally cold westerly air sourced out of the Canadian vortex seen here-

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-6-174.png?18

 

S

Not the 1st time this has showed in model output either.

[Grimsby Snow Lover]

Is this chart a positive one if a route towards cold in the UK is going to happen? The reason I ask is because the lows seem angled at a SE direction

http://www.wetterzentrale.de/pics/Rtavn1801.png

[nick sussex]

Snow lovers in the ne USA won't be happy if this low is shallower and heads further south into the Atlantic but hey do we care! It's a dog eat dog world in terms of snow!

 

Those  USA State forecasts which I often bore everyone with might come in handy here because they do often go into great detail with these set ups.

[SMU]

Best GFS for a while fits into my 6-8 JAN post from last night

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-0-240.png?18

 

Strongly negative AO, big Kumchatka High + developing Scandi high-

 

AWAITING THIRD PEICE OF THE PUZZLE FOR THE UK!

s

[Cloud 10]

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-2-168.png?18

 

Another snowy run for the west as the trough digs south in exceptionally cold westerly air sourced out of the Canadian vortex seen here-

 

http://modeles.meteociel.fr/modeles/gfs/runs/2013122818/gfsnh-6-174.png?18

 

S

 

-28 850's if the gfs is right,quite incredible.

 

 

 

Some interesting weather to come for the first week of 2014 with weather warning's

going into overdrive!

[Joe Levy]

Right at the end of the GFS we have a rather significant warming over the Greenland/Iceland region of the North Atlantic, an area where such a warming would be most welcome! Let's see if this appears on other runs

[nick sussex]

In terms of this possible storm over the NE USA which impacts the troughing near the UK this is the latest from the Massachusets area:

 

MODELS HAVE BEEN COMING AROUND TO A DEVELOPINGLOW PRESSURE SYSTEM. THE GFS HAD IT FIRST AND HAS MORE OF AN IMPACTALONG WITH THE CANADIAN MODEL. THE ECMWF SHOWED A LOW CLOSE TO THEREGION...BUT SCRAPING IT...AS RECENTLY AS THIS MORNING/S 00Z RUN.THE 12Z ECMWF BRINGS THE STORM JUST SOUTH OF LONG ISLAND AND MOVESNORTHEAST INSIDE THE BENCH MARK. SOME ENSEMBLE SUPPORT EXISTS FORTHIS STORM AS WELL...BUT SPREAD IS QUITE HIGH. THE 12Z GEFS MEANSTILL HAS THE STORM FAR OFFSHORE.THURSDAY AND FRIDAY...

 

SPREAD EXISTS DURING THIS PERIOD AS TO THEEXTENT OF THE LOW PRESSURE SYSTEM THAT MODELS HAVE BEEN SHOWING ASNOTED ABOVE. MODELS HAVE BEEN KEYING INTO A SOUTHERN PASS AT THISPOINT...BUT THE TRACK OF THE LOW CAN STILL CHANGE AS THE ENERGY ISSTILL OFFSHORE.That won't include info from the GFS 18hrs run and that does have a shallower system further south. 

Edited December 28, 2013 by nick sussex

[Tim Bland]

Cool and wet sums up the 18z GFS. Could be some transient sleet for low levels and snow in Scotland / high ground in the north . Nice to SE the stratos warming and jet going south at the far reaches of FI. I Think us coldies will have to be patient...I have a good feeling about end of Jan / early Feb

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=384&code=0&mode=5&carte=1

[Purga]

A dismal 18z just following the usual progression of lows across the Atlantic

 

Despite the odd slight hint at a bit of wintryness the overwhelming signal is zonal, rain & wind and a reforming vortex ruling the roost agaim.

[TSNWK]

A dismal 18z just following the usual progression of lows across the Atlantic

 

Despite the odd slight hint at a bit of wintryness the overwhelming signal is zonal, rain & wind and a reforming vortex ruling the roost agaim.

May I disagree with you there. It looked much better in high res and no doubt there would be some surprise snowfall events, all be it transient. Early low res looked interesting too with troughing heading south over us, yes the vortex powers up again over Greenland towards the end of low res.....

[bluearmy]

A dismal 18z just following the usual progression of lows across the Atlantic

 

Despite the odd slight hint at a bit of wintryness the overwhelming signal is zonal, rain & wind and a reforming vortex ruling the roost agaim.

So we ignore the snow and digging euro troughing it showed in high res and pay attention to the dross on low res??? Fwiw, i have no idea if its right but it seems odd to highlight the less likely and not mention the earlier timeframes which are clearly moreso.

Only just caught-up on this matter. We struggle enough with good faith analysis being misused or misquoted in certain newspaper titles. That's part of the territory of media relations; but it's troubling if some on this forum see it as fair game if undertaken within this discussion thread.

Ian, do you have any insight re whether the mention of sig colder in the 30 dayer has anything to do with the strat modelling?

[draztik]

So, have had a quick look through the 12z runs, and must admit nothing has changed much in my view. The anomaly charts for ecm/gfs t192-240 continue with a zonal flow, with little indication of a pattern change. Based on the 12z ops and ens from the main models, we continue to see a +NAO and -PNA forecast through mid Jan. So with this setup, its hard to see a vigorous cold spell developing for our region. Certainly, nothing major indicated away from the far North that is.

[Frosty.]

I'm happy the met office are mentioning a possibility of significantly colder weather eventually, without that carrot being dangled it would be grim but I see lots of cold zonality on the models in the next few weeks, especially for the north west. :-)

[fergieweather]

OK enough pls re that earlier issue! Returning to models: I am trying to ascertain the Dep Chief's rationale re the 16-30d forecast. Two possibles are either reference to the minority members in EC32 (last update of which ended run on 26 Jan) or some background signal from another product e.g. GloSea4, indicative of other possible driver such as SSW. When possible I'll report back what I can. Cheers.

[Joe Levy]

"SIGHS" Yes i think the point has been laboured and the stocks are now being prepared in earnest!!!.Oh anyone got any ens info?thanks in advance

Let's all move on now and concentrate on the model output - in answer to your question, the ens is still coming out, but to my eyes there are a fair few blocking options available so far at 288 hours

[UV-RAY]

"SIGHS" Yes i think the point has been laboured and the stocks are now being prepared in earnest!!!.Oh anyone got any ens info?thanks in advance

Take no notice , Tis not your fault some have the sense of humour of a dead rat. Back tot he model output and I'm more than pleased with today's viewing and a few of us have been championing this sort of set up over the last couple of weeks, this was before any potential Strat warming. IMO anywhere from the North. Midlands Northwards could see some snow over the next 10 days. Edited December 28, 2013 by Sceptical Inquirer

[SMU]

As we move along the days & runs so the signal grows to the North & East-

 

Becoming ever stronger...

 

1

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=1&mode=0&carte=1

 

3

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=3&mode=0&carte=1

 

4

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=4&mode=0&carte=1

 

8

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=8&mode=0&carte=1

 

15

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=15&mode=0&carte=1

 

18

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=240&code=18&mode=0&carte=1

 

lots of other blocking solutions- minimal zonal ones....

 

all in all 7/10 for todays efforts.

 

S

[Gael_Force]

OK enough pls re that earlier issue! Returning to models: I am trying to ascertain the Dep Chief's rationale re the 16-30d forecast. Two possibles are either reference to the minority members in EC32 (last update of which ended run on 26 Jan) or some background signal from another product e.g. GloSea4, indicative of other possible driver such as SSW. When possible I'll report back what I can. Cheers.

 

They have already mentioned a possible late winter SSW in the contingency planners forecast - I'm presuming this would be from the high-top Glosea - maybe now indicated to happen sooner than expected?

[Joe Levy]

The 18z ensembles are fully out. http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=312&y=141 (London) don't be deceived by the lack of deep cold runs. As both Steve Murr and I have posted, it is the synoptics that are more significant here with blocking to the Northeast very prevalent in this set. Were it to continue further, the 850s would drop away more than this. Certainly a promising set, but we must still be careful before getting overexcited.