Winter Model Discussion - Cold Hunting -12Z 06/01/13

[kumquat]

Never really looked at the precip charts on the ensembles charts much before. Is it unusual to see a precip outlier as far away from the pack as that?

[AWD]

Decidedly chilly me thinks;

[mattrout92]

First time I have posted on here, but some stunning 18z ensembles tonight!

Perturbation #11 bringing a brilliant Easterly, definitely feel there is the chance of something big next week

Matt

[fergieweather]

Shannon entropy is presently at extreme values heading into 4-5d period and this index of v low confidence expected to remain so for a few days. Latest UKMO-GM brings WBFL down to circa 200-300m widely Sat night into Sunday (by latter right across UK) but ppn detail remains problematic and this whole period presents some major forecast headaches at current juncture.

[Fozfoster]

Some mouth watering ensembles to go with the op run,the ensemble challenge is on!

Anyone beat that?

Yeah the real thing !!

[chris55]

Absolutely, charts can't even nail this Friday to Sunday yet.

Looking at even minuscule detail for Monday and there after, is craaaazy and will only lead to more moans and groans because their blizzard showing for 19th January has disappeared.

I would hope most people know that single runs or single ensemble sets are fun to watch unfold and great fun to comment on when they show "snowmageddon" but mean little with regards to the details.

Consistency is key, if we have lots of runs on the trot showing similar synoptics with the verification date coming closer with each run then we can take things a little more seriously.

[Dampdorset82]

Shannon entropy is presently at extreme values heading into 4-5d period and this index of v low confidence expected to remain so for a few days. Latest UKMO-GM brings WBFL down to circa 200-300m widely Sat night into Sunday (by latter right across UK) but ppn detail remains problematic and this whole period presents some major forecast headaches at current juncture.

In terms of temp and conditions for sleet and snow the mets confidence is creeping. Just the PPN is the major uncertainty at this stage......of course the conditions are quite likely to differ in the next 24 hours. But confidence seems to be slowly creeping up

[Canalboy]

Well, each forecast hour data is about 220mb. I can't get only what I need so I have to download everything. It's downloading at a speed of 150KB/s (yey for chineses internet lines!). Do the math About 30mins per file

Oh no please don't say do the math! We're not American! We gave them the language, it's Mathematics or bust

[Troubleatmill]

Shannon entropy is presently at extreme values heading into 4-5d period and this index of v low confidence expected to remain so for a few days. Latest UKMO-GM brings WBFL down to circa 200-300m widely Sat night into Sunday (by latter right across UK) but ppn detail remain i can realls problematic and this whole period presents some major forecast headaches at current juncture.

i can really believe that Ian, doubt we will be seeing a weekend forecast until later in the week Edited January 8, 2013 by Nick JB

[from russia with love]

gfs 18z op is NOT a outlier according to the ensembles however it is the pub run. The GFS 6z and 18z runs have the least data entered into them anyway. GFS and ECM 0z will be one of those runs which will be a building block for the end of the weekend/beginning of next week.

P.S- Save the pub run charts for years to come because the charts are amazing to see. Bookmark it, watch it and bring it in. (like the man city vs qpr winning goal)

[Panayiotis]

Ensembles for my area are amazing as the GFS 18z run isnt an outlier and has support!

Edited January 8, 2013 by Panayiotis

[lorenzo]

Cloud 10 to add to your request from earlier, not all easterly orientated, the carve up of the NH view within those ensembles is remarkable. Maybe these were the ones our Beijing correspondent was busy drawing in between uploading the CMA run..

After a couple of weeks of zonal output you have simply got to enjoy the sheer random output from all models on a run to run basis just now. Do not envy any of the professional forecasters one bit picking out short or medium guidance at the moment, migraine material.

[bradymk]

Ensembles for my area are amazing as the GFS 18z run isnt an outlier and has support!

Well it has support regarding 850 temps but not as much support regarding synoptics but thats expected as it was one of the snowiest runs i have seen for a long time and would provide the express with a successfull forecast Some stunning ensemble members and the mean dropping below and then hovering jist above -5c for all of the forecast period with some very cold runs also. Still endless possible outcomes, more and more seem to becoming colder however, what a horrible time to be chief forecaster at Exeter though with the weekend just the beginning of a very uncertain picture. Edited January 8, 2013 by bradythemole

[BLAST FROM THE PAST]

18z IS the synoptic set up I have been looking at.........attack from SW with Greenland HP extending SE towards us and Scandi, attack from the SW. GHP to strengthen and eally take hold afterwards....a la 18z. Timings look reasonable too...

love it...and snow at amounts not seen for some very long time.....marker down 16-22 memorable part of winter.

BFTP

Edited January 8, 2013 by BLAST FROM THE PAST

[Timmytour]

I just hope the next thread isn't tagged "The One After THAT GFS" <superstitious>

[mulzy]

A couple of nice day 14 charts from the latest CFS run (usual caveats apply) - just some more lovely eye candy!

Edited January 8, 2013 by mulzy

[EML Network]

Ensembles for my area are amazing as the GFS 18z run isnt an outlier and has support!

do you have a link for those ensembles ?? I.e where I can go find the one for my region ?

[bradymk]

do you have a link for those ensembles ?? I.e where I can go find the one for my region ?

on meteociel when it offers you the cities and a map of NW europe, just click on your location on the map and it generates them by lat and long. Edited January 8, 2013 by bradythemole

[john pike]

its you

[Cloud 10]

Cloud 10 to add to your request from earlier, not all easterly orientated, the carve up of the NH view within those ensembles is remarkable. Maybe these were the ones our Beijing correspondent was busy drawing in between uploading the CMA run..

After a couple of weeks of zonal output you have simply got to enjoy the sheer random output from all models on a run to run basis just now. Do not envy any of the professional forecasters one bit picking out short or medium guidance at the moment, migraine material.

Yes,some incredible charts appearing now and long may it continue.Incidentally i have found the

ensemble that wins the wooden spoon from the ensembles,13 unlucky for some.

[Panayiotis]

@EML Meteociel - Diagrammes ENS GFS nouvelle génération

[Mark Neal.]

A couple of nice day 14 charts from the latest CFS run (usual caveats apply) - just some more lovely eye candy!

I always knew the CFS was onto something!!

[Barmada Casten]

Hi guys,

So on what scale is this forecasting cold snap - are we talking cold/snow conditions on a level not seen for many-a-year.

Hope you are well,

Thanks BC

[The watcher]

And here we are, all winter, screaming for a Greenie High or a Scandi one......you wait for a bus all day and 2 come at once, springs to mind.

[fergieweather]

Very latest UKMO guidance just issued goes for the cold/v cold story predominanting into next week with potential sequence of battleground set-ups of snow to rain and back again in W/SW ; heavy snow potentially in any region; perhaps with a temporary relaxation of pattern but return of cold thereafter (MOGREPS keeping a N'rly well into 10-15d trend period).