General Model Output Discussion

[keithlucky]

Yes Nick,

I never though i would see runs like these.

Another bitterly cold run from the models tonight, the ECM particularly so. Quite a squeeze of sub zero easterlies at the weekend look to be odds on now. So frequent snow showers being driven well inland especially over the midlands and the south, nearest the low.

Amazing amount of snow for newcastle to kent nothing for central uk or west uk.

[NorthNorfolkWeather]

GFS+168.. ECM+168..

Quite a difference between gfs and ecm this evening with the ecm having a split polar vortex (again) which results in stronger blocking north and west.

Yet again, it looks as if the GFS is overcooking that Low pressure. If you look at the following ECM Charts, when we get to FI there is a chance of a Low sliding in from the Atlantic.

In my previous post I was thinking the Southerlies associated with it could come in towards the UK, having thought a little harder, I think we may have a somewhat different result with the Low sliding down into Southern France/Northern Iberia, again reinforcing the Easterlies

Edited January 5, 2010 by NorthNorfolkWeather

[blocky]

GFS+168.. ECM+168..

Quite a difference between gfs and ecm this evening with the ecm having a split polar vortex (again) which results in stronger blocking north and west.

I don't usually post but have paid an interest for a very long time reading th econtributions of many on here with great experience, so firstly a thanks to all of those who have helped me learn.

What sort of temperatures would we be expecting if the ECM easterly was to verify, coming from a very cold continent and lying snow, could places like Scotland be breaking the magic -20 oC??

[Frosty.]

The incredibly blocked pattern looks set to continue for another week at least and perhaps two more weeks if the models are to be believed tonight, a nice backtrack and huge upgrade from the gfs 12z with high pressure over scandinavia feeding snow flurries into most areas next week with mainly sub-zero temps throughout, the ecm 12z also amazingly cold with the high drifting north west instead of north east but still with a NE'ly flow and probable snow flurries, the ukmo 12z indicates an E'ly flow for next week as well. Before then it looks like E'ly winds across southern britain this weekend with frequent snow showers, drifting and severe frosts whereas scotland will become fine but bone chillingly cold with minus 20c likely in some scottish glens.

Edited January 5, 2010 by Frosty039

[TEITS]

What makes the ECM +96/+120 such an excellent run for me is the ENE,ly rather than a direct E,ly. This will push snow showers much further into the Midlands than a direct E,ly would.

My next attention goes to the +48 fax chart.

http://www.wetterzentrale.de/pics/brack1.gif

[Solar Cycles]

What makes the ECM +96/+120 such an excellent run for me is the ENE,ly rather than a direct E,ly. This will push snow showers much further into the Midlands than a direct E,ly would.

My next attention goes to the +48 fax chart.

http://www.wetterzentrale.de/pics/brack1.gif

These charts are just awesome, I keep having to pinch myself to see if I'm dreaming or not! Looking at that fax chart, I would say most of England would do well out off that.

[sebastiaan1973]

i've got already the temperatures for De Bilt based on the 12 run

6: -3/-7

7: -3/-6

8: -5/-10

9: -5/-7

10: -1/-3

11: -1/-3

12: -1/-3

13: -3/-5

14: -3/-5

15: -4/-6

[cooling climate]

Fantastic European output this evening again and it is literally leaving the GFS out in the cold I think.

For some reason unknown to me the GFS is really struggling with this set up.

The t120-168 charts are awesome to look at.

As I said in one of the other threads I wonder if the extended forcast from the Meto today had more

to do with wishcasting than anything else.

[Neilsouth]

Id still like to see a stronger north east flow though , too close to the high for friday and easterly winds for my liking

[Upgrade]

As I said in one of the other threads I wonder if the extended forcast from the Meto today had more

to do with wishcasting than anything else.

what was the wishcasting?

Indeed.Good consistency from run to run and that chart full of possibiliies for more snowy troughs,especially for the more Eastern areas.

It`s very quiet in here but i guess ,like me,we are all enjoying the snow falling in many areas and posting in the regionals.

Indeed - if that easterly comes off there will be embedded features,troughs, extended shower / streamer events and the rest. amazing! lets hope it happens!

[Matt12]

I read on the BBC news website (and elsewhere on the Internet) that the negative AO is the principal cause of the unusually cold conditions so far this winter (not sure what this is exactly - excuse my ignorance!). Is the AO likely to stay negative for the considerable future, bringing with it the chance for more prolonged cold?

[Optimus Prime]

AO

NAO

PDO

All together have huge effects.

As you can see stays very negative for the foreseeable

Edited January 5, 2010 by Optimus Prime

[Michael Fishermans Friend]

Yeah some great great synoptics at the moment which look like lasting for at least another week, it looks at some point over the next day or so and into the weekend a majority of people are going to see some form of snow or covering. These synoptics look like bringing us the most continuous form of blocking since at least 97 (in the south) and probably back to the 80's towards the North.

Looks like Friday and into the weekend the all important feature will be the direction of the wind which could possibly vary from day to day - maybe anything from a ENE to a NNE going by the various models so again who and where gets the most snow might come down to looking at the direction and strength of the wind to see how far inland these convective showers get.

Just sitting back and enjoying the synoptics for now - they don't come about like this often!

[tinybill]

i know its a long way off but if this comes off god knows what going to happen

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

AO came in at -3.413 for December! At a glance that looks like the lowest monthly mean since 1950!

http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/monthly.ao.index.b50.current.ascii.table

[Michael Fishermans Friend]

i know its a long way off but if this comes off god knows what going to happen

yeah thats going by the GFS model which is showing more of a North Easterly favouring Kent and the NE coast of Norfolk/Suffolk, whilst the ECM and UKMO going by their output tend to have more of an ENE favouring the streamers and wider coastal areas.

Edited January 5, 2010 by Timmy H

[Neilsouth]

i know its a long way off but if this comes off god knows what going to happen

Why does it show Rain? :blink:

[Optimus Prime]

Why does it show Rain?

It's not the precip type chart its just shows you where plain old rain would fall and intensity.

[Oblix]

Anyone know whats happened to the "system" that was predicted last Sunday to be coming over the south eastern UK this weekend?

[Cloud 10]

The ensembles are out for the 12z ecm and show that the operational run was less cold compared to the mean and the control run.

It really is quite unbelievable that a run such as that can be one of the "milder" solutions.

[NL]

What makes the ECM +96/+120 such an excellent run for me is the ENE,ly rather than a direct E,ly. This will push snow showers much further into the Midlands than a direct E,ly would.

My next attention goes to the +48 fax chart.

http://www.wetterzen...pics/brack1.gif

Yeah the one which is prefered here too, as right on the coast a straight easterly can often result in sleet but Nor'easterlies nearly always deliver. Just want to point out that temps here on the NE coast are up to +3.3°C (sst in effect) but ppn is of graupel/hail and snow and no thaw...!!

Anyway would like to say these charts are a reminder that no matter how much money we throw at trying to understand the chaotic world of weather it will turn understanding on its head.... Oh how i love the British weather.

Whilst everyone is busy with their region threads i'd like to take the opportunity to express thanks to some on here that prompted myself to tell people to expect a 70-80's type winter way back in September...

[mcweather]

Tonights glorious ECM run was a mild outlier. Never mind 1963 I,m thinking 1740 or 1684 :lol:

[damianslaw]

Developments today reinforce once again how difficult it is for the computer models be very accurate beyond 24 hours or so, even this time yesterday none were necessarily showing such a deepening of the current low positioned over the midlands and consequent intensification of the front currently sat over central and southern england.

With this in mind, take any details being shown by the models 24 hours+ including the FAX charts with a pinch of salt. As I said yesterday in unstable arctic flows, pinpointing where troughs or where lower pressure heights may occur 24 hours in advance is almost impossible.

Still the models can be trusted with the general synoptical evolution being shown for the rest of the week and this is for the north/north easterly flow to change to a more easterly flow by Friday courtesy of ridging of heights out of Scandanavia. At this stage it looks like most shower activity will occur in the south east, with northern Britain potentially on course for what could be a truely bitter yet brilliantly sunny wintry scene - fantastic skiing and winter mountaineering conditions, it isn't normally until Feb when a deep easterly sets in, so it is looking a real bonus for the time of year, given how awfully wet and windy this time of year usually is.

Potential for those projected -20 degree temps or lower to be recorded over Scotland this weekend I feel and very low minima in northern england.

AO and NAO look staying negative well into next week - long term theme northern blocking will remain supreme.

[Duane S.]

Tonights glorious ECM run was a mild outlier. Never mind 1963 I,m thinking 1740 or 1684 :o

Hi Mark. Gosh it's hard living in this county at times. That LP I was so hoping for appears but decides to park itself right over us at the wrong time, couldn't write it!

Just seen the ECM and I have to say I am stunned. What a chart

MJO crawling around to phase 5 which has got to be good in this situation and the AO is scheduled to tank again after a brief 'recovery' to the giddy heights of around -2. Signs of an possible impending MMW for Feb and DESPITE the fact I haven't seen one solitary snowflake this winter, this really is an icredible winter so far (in fact whatever happens from now on in)

The ensembles are out for the 12z ecm and show that the operational run was less cold compared to the mean and the control run.

It really is quite unbelievable that a run such as that can be one of the "milder" solutions.

Mindblowing. I want to see the charts from that run that dips down to -23 in deep FI! Must be fairly interesting

[tinybill]

Anyone know whats happened to the "system" that was predicted last Sunday to be coming over the south eastern UK this weekend?

its coming news 24 weather is already warned the east of heavy snow Saturday