Jump to content
Will it snow? 7 day forecast Weather Radar Will it be cold?
Snow?
Local
Radar
Cold?
IGNORED

General Model Output Discussion

grab my graupel

By grab my graupel
in Spring Weather Discussion

 Share

Recommended Posts

kold weather Maestro

kold weather

Posted
  • Location: Liphook
  • Location: Liphook
Posted

Also the GFS control run also evolves in a decent fashion after a very dodgy period before 168hrs...

I'd say about 70% are better then the GFS op run BUT most runs only get cold away from Scotland after the 5th of Jan. If the low gets shunted southwards then what the GFS expects then obviously it'll kick in before then.

Looks better then I was expecting from the ensembles, esp in the longer term...backs up my idea that the 18z GFS was WAY too progressive with lowering of heights.

Link to comment
Share on other sites
TEITS Maestro

TEITS

Posted
  • Location: Peterborough N.Cambridgeshire
  • Location: Peterborough N.Cambridgeshire
Posted

I Havent got the UKMO 18z- it used to be on the tropical Experimental site which was handy- but its gone from there- So I need that one as well-

ECM uppers & PPN Charts-

http://en.vedur.is/weather/forecasts/atlantic/#type=prec

S

Cheers Steve.

Just been looking at the ensemble mean upto +192 and im pleased to say the GEFS ensembles are backtracking. They are not quiet there yet but this is often the case with the ensemble mean.

Link to comment
Share on other sites
Duane S. Veteran

Duane S.

Posted
  • Location: Weymouth, Dorset
  • Location: Weymouth, Dorset
Posted

I think the point is that all the models handle mild weather much better, as they are more familiar with forecasting it.

Synoptics such as we have at the moment have probably cropped up less than ten times in the past 25 years, there is no wonder they are struggling with the details...

That is quite probably true. I am guessing the models factor in some historical data within its algorithms? If that is the case then it would be a very plausable part explanation. Although you may then say why doesn't the ECM show this? I suppose the answer to that would be in the hands of the model programmers themselves.

Link to comment
Share on other sites
nick sussex Maestro

nick sussex

Posted
  • Location: Eastbourne and Larnaca,Cyprus .
  • Location: Eastbourne and Larnaca,Cyprus .
Posted

I Havent got the UKMO 18z- it used to be on the tropical Experimental site which was handy- but its gone from there- So I need that one as well-

ECM uppers & PPN Charts-

http://en.vedur.is/weather/forecasts/atlantic/#type=prec

S

Heres the link Steve, it's very informative and does have all the ukmo output including the 48hrs model runs.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=nae&MODELLTYP=1&BASE=200912271800&VAR=prty&HH=48&ZOOM=0&ARCHIV=0&WMO=

Link to comment
Share on other sites
rich1 Newbie

rich1

Posted
  • Location: nr Guildford, surrey
  • Location: nr Guildford, surrey
Posted

Faxes appear to be backing the ECM to a large degree, they seem to think that run is nonsense

lets put it this way, had all the others and the faxes been mild and the GFS 18z was cold it would be seen as one for the dustbin all round bar a few wild optimists going by that particular run's history

hey, it could be right but...nah, as it is this winters patterns are not the norm as what we have experienced in recent years so I feel that evolution remains at the back of the queue presently

if it is wrong, that probably relegates it in to the cannon fodder bracket but we will see. I expect the ensembles to show a bit of a split but support it this time in the short range s they did with the last one. Maybe by the 00z it may finally show signs of falling in to line however

Link to comment
Share on other sites
casparjack Rookie

casparjack

Posted
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
  • Weather Preferences: Absolutely anything extreme or unusual
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
Posted

That is quite probably true. I am guessing the models factor in some historical data within its algorithms? If that is the case then it would be a very plausable part explanation. Although you may then say why doesn't the ECM show this? I suppose the answer to that would be in the hands of the model programmers themselves.

I suspect that might come down to the origins of the models, US against European - don't know for sure just speculating... pardon.gif

Link to comment
Share on other sites
snowmadchrisuk Enthusiast

snowmadchrisuk

Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset
Posted

I don't know if it means this is going to be all brought forward by a few hours but Tuesday's low is already showing up on radar .

http://www.metoffice.gov.uk/weather/uk/radar/index.html

Link to comment
Share on other sites
Guest North Sea Snow Convection

Guest North Sea Snow Convection

Posted
Posted (edited)

It should be remembered that the GFS is suggesting the same old evolution of the low that the UKMO was suggesting yesterday but has since come into line over two outputs with both the ECM and more especially the GEM. Plus the ensembles on both the ECM and GEM have become ever more bullish about a significant cold spell from the north east. Plus we have updated faxes late this evening that support the euro stance.

So who do we believe tomorrow?

Edited by North Sea Snow Convection
Link to comment
Share on other sites
Duane S. Veteran

Duane S.

Posted
  • Location: Weymouth, Dorset
  • Location: Weymouth, Dorset
Posted

All this talk of relegating the GFS etc. A lot of people were saying the ECM is FINISHED as a respectable model! after it went doolaly for a couple of days a week or so ago. :lol:

Link to comment
Share on other sites
casparjack Rookie

casparjack

Posted
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
  • Weather Preferences: Absolutely anything extreme or unusual
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
Posted

I don't know if it means this is going to be all brought forward by a few hours but Tuesday's low is already showing up on radar .

http://www.metoffice...adar/index.html

Rather worryingly it's already showing up as a huge feature on the Netweather radar, been watching it for a few hours now...

Link to comment
Share on other sites
cooling climate Aficionado

cooling climate

Posted
  • Location: hertfordshire
  • Location: hertfordshire
Posted

I would not give the GFS 18z any credence what so ever as it flies in the face of all other

model outputs tonight.

The latest fax chart is out for t120 and shows the 528 line well south of the UK with a low

situated over n/w France and a front straddling the southeast.

A very wintry picture indeed.

Link to comment
Share on other sites
snowmadchrisuk Enthusiast

snowmadchrisuk

Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset
Posted

Rather worryingly it's already showing up as a huge feature on the Netweather radar, been watching it for a few hours now...

Yes that first band of precipitation was suppose to go east , but it is heading North towards us.

Link to comment
Share on other sites
john mac Aficionado

john mac

Posted
  • Location: Waltham Abbey, West Essex 144ft a.s.l.
  • Weather Preferences: snow, thunderstorms
  • Location: Waltham Abbey, West Essex 144ft a.s.l.
Posted

Well my last post tonight, i hope i wake up to a nice backtrack from the 00z night all

Link to comment
Share on other sites
casparjack Rookie

casparjack

Posted
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
  • Weather Preferences: Absolutely anything extreme or unusual
  • Location: Nuneham Courtenay, Oxfordshire - 275 ft AMSL
Posted

I would not give the GFS 18z any credence what so ever as it flies in the face of all other

model outputs tonight.

The latest fax chart is out for t120 and shows the 528 line well south of the UK with a low

situated over n/w France and a front straddling the southeast.

A very wintry picture indeed.

That's true, but the 528 on the earlier runs is well North, much further than I had hoped, I have an awful feeling that unless we have a significant change, that much of the precipitation at lower levels will fall as rain for the first 24 hours in the Midlands and areas South of them.

I appreciate that there is cold air at the surface, but if you look at the 850s on the radar overlay they don't support snowfall and I can't see that changing for 36-48 hours where I am, even though I am over 500 ft amsl...

Link to comment
Share on other sites
keithlucky Experienced

keithlucky

Posted
  • Location: swansea craig cefn parc 160 m asl
  • Location: swansea craig cefn parc 160 m asl
Posted

Yes that first band of precipitation was suppose to go east , but it is heading North towards us.

All charts i have seen says the front stalls over the m4 corridor you may get a few showers but i think you to far north.
Link to comment
Share on other sites
kold weather Maestro

kold weather

Posted
  • Location: Liphook
  • Location: Liphook
Posted

Ensembles show very nicely how overly progressive with the decay of the heights over the Arctic was, only 2 ensemble members synoptically support the 18z GFS op run with regards to the eventual evolution of the upper Greenland high...so whilst not quite an outlier its on the end of what is possibly the worst case could be.

FWIW the control run is a bit of a stunner for cold conditions, nice cold NE airflow followed by generally slack conditions.

So whilst I wouldn't rule out the 18z evolution I'd put it to the back of your mind, for now its got decent enough support (though stil lnoticeable scatter TBH) for the first 72hrs, beyond that and not much agreement between any of the ensembles...most end up cold though in the end!

Link to comment
Share on other sites
snowlover2009 Apprentice

snowlover2009

Posted
  • Location: leeds
  • Location: leeds
Posted

well in a way what ever happens for early this week i will be happy as such. if the low is furthe rnorth which i very much doubt then it would bring much more snow potential here although if gfs came off for later then it would be a disaster just like the model is anyway. but ecm, ukmo, fax, gem, gme and jmd and nogaps have the low to the south. all 7 remaining models coming in line for just one other model gfs,which has the least verfication to me, seems very unlikely

Link to comment
Share on other sites
cyclonic happiness Accomplished

cyclonic happiness

Posted
  • Location: Bedworth, North Warwickshire 404ft above sea level
  • Location: Bedworth, North Warwickshire 404ft above sea level
Posted

Yes that first band of precipitation was suppose to go east , but it is heading North towards us.

no no no...that stuff you see on the radar is far too progressive....it's really still out in the mid atlantic silly! :D:p

Link to comment
Share on other sites
Guest
This topic is now closed to further replies.
 Share
Go to topic listing
×
×
  • Create New...